SPACE
MEDICINE
To Planet 9 . . . and Beyond! p.70
Crowdsourcing Cancer Research p.24
SCIENCE FOR THE CURIOUS
®
SCIENCE of AGING Does DNA hold the secrets to longevity? p.28
PLUS
The Power of One Brain Drilling to Doomsday The Science Behind Your Credit Score p.18
p.50
p.42
BONUS ONLINE CONTENT CODE p.5
A
B LL Bu ig -NE tt ge W on r s
s o N act r nt Co
“My friends all hate their cell phones… I love mine!” FR EE Car Charg er Here’s why.
Say good-bye to everything you hate about cell phones. Say hello to the ALL-NEW Jitterbug Flip. “Cell phones have gotten so small, I can barely dial mine.” Not the new Jitterbug® Flip. It features a larger keypad for easier dialing. It even has a larger display so you can actually see it. “I had to get my son to program it.” Your Jitterbug Flip set-up process is simple. We’ll even program it with your favorite numbers. “I tried my sister’s cell phone… I couldn’t hear it.” The Jitterbug Flip is designed with a powerful speaker and is hearing aid compatible. Plus, there’s an adjustable volume control. “I don’t need stock quotes, Internet sites or games on my phone. I just want to talk with my family and friends.” Life is complicated enough… The Jitterbug Flip is simple. “What if I don’t remember a number?” Friendly, helpful Operators are available 24 hours a day and will even greet you by name when you call. “My cell phone company wants to lock me in a two-year contract!” Not with the Jitterbug Flip. There are no contracts to sign and no penalty if you discontinue your service.
Order now and receive a FREE Car Charger for your Jitterbug Flip – a $25 value. Call now!
Monthly Plan
$14.99/mo
$19.99/mo
Monthly Minutes
200
600
Operator Assistance
24/7
24/7
Long Distance Calls
No add’l charge
No add’l charge
Voice Dial
FREE
FREE
Nationwide Coverage
YES
YES
30 days
30 days
Friendly Return Policy
1
More minute plans available. Ask your Jitterbug expert for details.
“I’d like a cell phone to use in an emergency, but I don’t want a high monthly bill.” The Jitterbug Flip has a plan to fit your needs… and your budget. “Many phones have features that are rarely needed and hard to use!” The Jitterbug Flip contains easy-to-use features that are meaningful to you. A newly designed built-in camera makes it easy and fun for you to capture and share your favorite memories. And a new flashlight with a built-in magnifier helps you see in dimly lit areas, the Jitterbug Flip has all the features you need.
Available in Red and Graphite.
Enough talk. Isn’t it time you found out more about the cell phone that’s changing all the rules? Call now, Jitterbug product experts are standing by.
NEW Jitterbug Flip Cell Phone Call toll-free to get your Jitterbug Flip. Please mention promotional code 103880.
1-877-624-4135
www.jitterbugdirect.com 47665
We proudly accept the following credit cards:
IMPORTANT CONSUMER INFORMATION: Jitterbug is owned by GreatCall, Inc. Your invoices will come from GreatCall. Plans and Services require purchase of a Jitterbug phone and a one-time setup fee of $35. Monthly fees do not include government taxes or assessment surcharges and are subject to change. Coverage is not available everywhere. 5Star or 9-1-1 calls can only be made when cellular service is available. 1We will refund the full price of the Jitterbug phone and the activation fee (or setup fee) if it is returned within 30 days of purchase in like-new condition. We will also refund your first monthly service charge if you have less than 30 minutes of usage. If you have more than 30 minutes of usage, a per minute charge of 35 cents will be deducted from your refund for each minute over 30 minutes. You will be charged a $10 restocking fee. The shipping charges are not refundable. There are no additional fees to call GreatCall’s U.S.-based customer service. However, for calls to a GreatCall Operator in which a service is completed, you will be charged 99 cents per call, and minutes will be deducted from your monthly rate plan balance equal to the length of the call and any call connected by the Operator. Jitterbug and GreatCall are registered trademarks of GreatCall, Inc. ©2016 GreatCall, Inc. ©2016 firstSTREET for Boomers and Beyond, Inc.
Three exclusive tour packages!
8HTYYXIFQJ &WN_TSF 5FHNDŽH3TWYM\JXY 8FS+WFSHNXHT
Experience
AMERICA’S 2017 TOTAL SOLAR ECLIPSE August 21, 2017 The most awe-inspiring celestial sight is coming to the U.S. for the first time in 26 years. Skywatchers across 12 states can experience darkness at midday as the Moon passes in front of the Sun in a total solar eclipse.
America’s Music Cities
It’s an event you don’t want to miss, and Discover is here to help you make the most of it. Working with TravelQuest International and the editors at our sister magazine, Astronomy, we’re offering three exclusive tour packages that celebrate the many cultural treasures America has to offer.
Surrounding the August 21 total solar eclipse, you can: • Enjoy jazz, blues, country, and rock ’n’ roll in New Orleans, Nashville, and Memphis • Experience the spectacular scenery of the Pacific Coast from Seattle to San Francisco
© Javarman | Dreamstime.com
• Journey through the pristine forests and snowcapped mountains of the West’s National Parks
CHOOSE AN ECLIPSE EXCURSION TODAY! ;NXNY\\\FXYWTSTR^HTRJHQNUXJYTZWX
Discover SCIENCE FOR THE CURIOUS
®
M AG A Z I N E
P27012
Contents OCTOBER 2016 VOL. 37, NO. 8
About 66 million years ago, an asteroid plummeted into the Gulf of Mexico and changed life on Earth forever. See page 42.
4
DISCOVERMAGAZINE.COM
Website access code: DSD1610 Enter this code at: www.DiscoverMagazine.com/code to gain access to exclusive subscriber content.
FEATURES
28 What It Takes to Reach 100
Live long and prosper, as the Vulcan salute goes. Some people have managed that first part much better than others, and the key could be in their DNA. BY LINDA MARSA
36 Your Attention, Please
MIT neuroscientist Earl Miller has made a name for himself with his research on working memory, the brain’s scratchpad. His next goal? To make us all smarter.
ON THE COVER
BY ADAM PIORE
To Planet 9 . . . and Beyond! p.70
42 Drilling to Doomsday
Beneath the Gulf of Mexico lies evidence of one of Earth’s most cataclysmic events. Now, experts are getting their closest look yet. BY ERIC BETZ
50 Weapons of Math Destruction
Sure, credit scores are important, but they hold more sway than you’d think. And in many cases, that can be a very bad thing. BY CATHY O’NEIL
Crowdsourcing Cancer Research p.24 Science of Aging p.28 The Power of One Brain p.18 Drilling to Doomsday p.42 Science Behind Your Credit Score p.50 Cake photo: William Zuback/Discover; DNA candle: Jay Smith; background: Melis/Shutterstock
COLUMNS & DEPARTMENTS 6
EDITOR’S NOTE
Chasing Longevity Living to 100 takes a stroke of genetic luck and a dose of resilience.
7
24
BIG IDEA
Fighting Cancer With Data
THE CRUX
How experts plan to give the Ignorosphere some love, an update on surgeon Anthony Atala’s work on 3-D bioprinting, we add to our blog family and more!
18 PROGNOSIS A Mind in Time Researchers are spending some quality one-on-one time with patients’ brains. The results could steer the course for future clinical treatment. BY ADAM HADHAZY MARK GARLICK
Lady Macbeth’s book and try washing your hands. It works, and neuroscience backs it up. BY MALLORY LOCKLEAR
22 MIND OVER MATTER
Think Outside the Brain
Cracking the human genome means doctors can now personalize cancer treatments. But not without teamwork and a whole lot of computing power. BY AIMEE SWARTZ
70
OUT THERE
74
NOTES FROM EARTH
The Judas Fish In Montana, the invasive lake trout is choking native fish populations. With a secret weapon, ecologists are finally turning the tide. BY JANINE LATUS
78
HISTORY LESSONS
A Profile of Plague The deadly pestilence of old is still around, and scientists are learning about its past and future. BY HILLARY WATERMAN
To Planet 9 — and Beyond!
82
Past the celestial body formerly known as a planet, i.e., Pluto, astronomers are continuing their hunt for the elusive Planet 9. BY COREY S. POWELL
Forget your stereotypes, there’s more to these winged mammals of the dark than vampire lore. BY GEMMA TARLACH
20 THINGS YOU DIDN’T KNOW ABOUT … BATS
57 OUT THERE SPECIAL BONUS SECTION Crucial tips for your 2017 eclipse planning, the amateur astronomer who beat NASA to the punch with his observations of Saturn, and how one legendary meteorite hunter has turned his eyes from the ground to the skies.
Feeling guilty? Take a page from
October 2016 DISCOVER
5
Discover SCIENCE FOR THE CURIOUS
Editor's Note
®
BECKY LANG Editor In Chief DAN BISHOP Design Director
Chasing 100, With Cellular Mechanics Resilience. For those who live into their 90s and past 100, it’s a crucial part of the equation, as you’ll find out in our cover story (see page 28). It’s grounded them through wars, the Depression, civil unrest and their individual daily stressors. The notion of resilience has been running through my head lately, as I’ve watched footage from the aftermath of police shootings and terror attacks. What does it take to prevail through that kind of pain, both on an individual basis and across society? I would argue that resilience in the face of today’s social upheaval is so grounded, it’s in our bones, it’s in the very structure of our cells. It’s those cellular mechanics — the clockwork — that appear to drive how we age. The notion of a timekeeper is at the heart of some researchers’ work to crack the code of aging. For most of us, the very process of aging eventually dooms us to disease. But for those of us who live beyond 100, it’s as if the cellular clocks have slowed down. In addition, scientists have found that how these centenarians live makes a difference. A safety net of friends and family. Plenty of walking. Real food. Experiences throughout their lives will shape how their genes function. In the quest for longevity, here’s to a big dose of resilience and a way to slow down that cellular ticktock.
EDITORIAL KATHI KUBE Managing Editor GEMMA TARLACH Senior Editor BILL ANDREWS Senior Associate Editor ERIC BETZ Associate Editor LACY SCHLEY Assistant Editor DAVE LEE Copy Editor ELISA R. NECKAR Copy Editor AMY KLINKHAMMER Editorial Assistant BRIDGET ALEX AAAS Mass Media Fellow Contributing Editors
DAN FERBER, TIM FOLGER, LINDA MARSA, STEVE NADIS, ADAM PIORE, COREY S. POWELL, JULIE REHMEYER, ERIK VANCE, STEVE VOLK, PAMELA WEINTRAUB, JEFF WHEELWRIGHT, DARLENE CAVALIER (SPECIAL PROJECTS)
ART ERNIE MASTROIANNI Photo Editor ALISON MACKEY Associate Art Director
DISCOVERMAGAZINE.COM CARL ENGELKING Web Associate Editor NATHANIEL SCHARPING Web Staff Writer Bloggers
MEREDITH CARPENTER, LILLIAN FRITZ-LAYLIN, JEREMY HSU, REBECCA KRESTON, JEFFREY MARLOW, NEUROSKEPTIC, ELIZABETH PRESTON, SCISTARTER, CHRISTIE WILCOX, TOM YULSMAN
ADVERTISING STEVE MENI Advertising Sales Manager 888 558 1544
[email protected]
Rummel Media Connections KRISTI RUMMEL Consulting and Media Sales 608 435 6220
[email protected]
MELANIE DECARLI Marketing Architect BOB RATTNER Research DARYL PAGEL Advertising Services
KALMBACH PUBLISHING CO. CHARLES R. CROFT President STEPHEN C. GEORGE Vice President, Content DANIEL R. LANCE Senior V.P., Sales & Marketing JAMES R. MCCANN Vice President, Finance NICOLE MCGUIRE Vice President, Consumer Marketing JAMES SCHWEDER Vice President, Technology ANN E. SMITH Corporate Advertising Director MAUREEN M. SCHIMMEL Corporate Art Director KIM REDMOND Single Copy Specialist MIKE SOLIDAY Art and Production Manager
SUBSCRIPTIONS In the U.S., $29.95 for one year; in Canada, $39.95 for one year (U.S. funds only), includes GST, BN 12271 3209RT; other foreign countries, $44.95 for one year (U.S. funds only).
Feel free to send comments and questions to
[email protected]
[email protected] 21027 Crossroads Circle, Waukesha, WI 53186
facebook.com/DiscoverMag twitter.com/DiscoverMag plus.google.com/+discovermagazine
DISCOVERMAGAZINE.COM
800 829 9132 Outside the U.S. and Canada: 813 910 3616 Customer Service:
[email protected] Digital:
[email protected] Back Issues:
[email protected]
EDITORIAL INQUIRIES
CONNECT WITH US
6
CUSTOMER SALES & SERVICE
WILLIAM ZUBACK/DISCOVER
Becky Lang
THE
CRUX
The Latest Science News & Notes
LIFE’S LIMITS They might be tiny, but these microscopic plankton fossils, called planktonic foraminifera, are a nearly continuous 65 million-year record of life on Earth. University of Southampton evolutionary ecologist Thomas Ezard and his team compared the collection’s number of species with markers of ocean temperature and sediment composition during their life spans. Data revealed a broader picture of how environmental variations affect biodiversity. Cardiff University earth scientist Paul Pearson took this composite photo of Ezard’s subjects, each less than a millimeter wide, with a scanning electron microscope. ERNIE MASTROIANNI; PHOTO BY PAUL PEARSON/CARDIFF UNIVERSITY
October 2016 DISCOVER
7
THE
CRUX
Destination: Ignorosphere All aboard, scientists studying climate change. Ever heard of the Ignorosphere? It’s what scientists have jokingly nicknamed the mesosphere, the third atmospheric layer from Earth’s surface. It’s always been tough for researchers to access and so has been largely ignored. But that’s about to change, thanks to work done by Project PoSSUM (Polar Suborbital Science in the Upper Mesosphere). While unmanned rockets, satellites and balloons — most notably NASA’s AIM satellite — have taken images of and collected data from the layer in the past, new suborbital vehicles will make it possible to send actual human scientists to the mesosphere to study noctilucent (NLC) clouds. These ragged, spidery clouds began appearing in the late 1800s, and their increasing frequency and geographic spread are believed to be a marker for climate change. They’ve been difficult to study, however: They’re too high for detailed data collection via ground-based instruments, balloons or aircraft, and too low for orbital satellites. The complex equipment that can measure fine-scale changes in the clouds’ composition needs a human operator. Noctilucent clouds Project PoSSUM’s executive director, Jason Reimuller, says suborbital rocket planes are scheduled to launch from Alaska in 2018. They’ll head into the Ignorosphere with scientific instruments like the ones pictured here. CAROLINE BARLOTT
Making Manned Flights Possible PoSSUM plans to use XCOR Aerospace’s suborbital rocket plane Lynx; two people fit in its flight pod.
Unlike commercial planes, which can use the lower atmosphere’s oxygen to give their fuel systems a boost, suborbital rocket planes use liquid oxygen tanks to compensate for the thin air and get the thrust they need.
8
DISCOVERMAGAZINE.COM
CLOUDS: JAN ERIK PAULSON/ NASA EARTH OBSERVATORY
Extra Thrust Required
Thermosphere
+4.6 MINUTES
During the 30-minute round-trip flight, PoSSUM personnel will only have about four minutes to collect data.
MICROGRAVITY ENVIRONMENT 328,000 feet
350,000 325,000 300,000 275,000
ENGINES OFF 190,000 feet
Glide and circle
250,000 225,000 200,000 175,000 150,000
Horizontal landing
Stratosphere
Horizontal takeoff
125,000
Troposphere
Powered ascent
MAX AIRSPEED: MACH 2.9
50,000
Altitude (feet)
Coast upward
Mesosphere
+3 MINUTES
Re-entry
100,000 75,000
25,000 0
These rocket engines can be used for thousands of flights, potentially making scientific ventures more affordable.
LYNX PLANE, FLIGHT PLAN AND ENGINE TEST: XCOR; EXPERIMENTS FROM LEFT: PROJECT POSSUM; ZOLTAN STERNOVSKY; GERALD LEHMACHER
Rocket engine test
PoSSUM’s Technology In addition to shooting traditional video of the NLC clouds, an automated infrared imager will record a layer of molecules — the airglow — that sits just above them. The images will give experts a better idea of the mesosphere’s overall structure.
As the vehicle passes through clouds, a shoebox-sized instrument will capture air to compare carbon dioxide and nitric oxide levels with surface levels.
An aerosol sampler will collect fine particles from the atmosphere, believed to be leftover meteor bits, which may explain how the clouds form in the first place.
The Mesosphere Clear Air Turbulence instrument will use pressure data to calculate temperatures that will help determine how the clouds grow.
October 2016 DISCOVER
9
THE
CRUX
The Lure of the Landfill Birds give up on migrating and gorge on garbage instead. trips from their permanent nests to landfills dozens of miles away — something previously unheard of. some European birds would vanish Aldina Franco and a team from after summer and reappear in the University of East Anglia spring. A hunter in Mecklenburg, followed the birds as they feasted Germany, killed a white stork that behind dump trucks dropping already had an African projectile off discarded meat at a landfill. lodged in its neck. Nearly Incredibly, the steady supply has two centuries later, European allowed stork populations to researchers are trying to explain increase tenfold since the 1980s. a new phenomenon: Why have “The landfill food enables the many storks stopped migrating? storks to raise a larger number of Roughly 14,000 of the fairchicks per nest,” Franco says. weather fowl in Portugal have The storks are just one of many given up flying south. In a recent The easy access to food is just too enticing for white storks in species shifting their migration study published in the journal Portugal. The birds have stopped migrating in favor of feasting at garbage sites like this one. patterns because of human behavior. Movement Ecology, conservation And these birds might soon reroute ecologists used GPS tags to track again: The European Union recently revised landfill rules so that 17 of those white storks through their normal migration period food waste is handled under cover. That could leave the storks to figure out why. looking elsewhere for their junk-food fix. ERIC BETZ Instead of heading to sub-Saharan Africa, the birds made regular
10
DISCOVERMAGAZINE.COM
Huge selection! Please give order code Z096
Books • Magazines Globes & Maps • Posters Downloads • And more!
.com MyScienceShop P27902
UNIVERSITY OF EAST ANGLIA
In 1822, a well-placed arrow solved the mystery of why
TH AT WOR D YOU HEA R D
No, it’s not the little glob that clogs up your Elmer’s bottle. A glueball is a particle comprising only other particles called gluons, which have no mass. Gluons are the force particles that hold together quarks, which make up protons and neutrons. That means a glueball is made up entirely of force. And scientists can’t even observe this unstable particle; they can only detect it by trying to calculate its decay. But in 2015, researchers announced a promising new calculation technique that could help them finally pin down the elusive glueball. LACY SCHLEY; ILLUSTRATION BY CHAD EDWARDS
October 2016 DISCOVER
11
THE
CRUX
ReDISCOV ER
A Faster Way to 3-D Printed Organs New tech makes bioprinting more efficient. In 2001, Anthony Atala became the first surgeon to build a human bladder and implant it, helping pioneer the field of bioprinting. At the time, Atala was using a multistep process. First, he would create a frame from biodegradable, synthetic polymers, which are essentially plastics. Then he’d paint cells grown from the patient’s bladder onto the frame with a custom 3-D printer — a technique Discover detailed in a profile of Atala last year. Now, Atala and a team from the Wake Forest Institute for Regenerative Medicine have combined both processes with a new tabletop device called an integrated tissue organ printer. A scanner traces the patient’s body part, creating instructions for the printer’s three ink nozzles. The “ink” is a clear gel mixture of mature tissue cells, immature stem cells and polymers designed to mimic real tissues’ consistency. The ink looks syrupy at first, then hardens to resemble the texture The new, simplified organ-printing system developed of gelatin. It’s printed in a layered by Anthony Atala and his team is hard at work lattice, which leaves tiny channels creating a jawbone structure. throughout the organ that act like blood vessels and allow nutrients to be dispersed through the tissue. Atala has now printed an ear, jawbone and muscle tissue with the integrated printer, all of which held their shape after being implanted into rodents. Blood vessels grew into the microchannels, and the rodents’ cells proliferated, making the implanted tissue more resilient over time. Printed, personalized organs for human transplants are a long way off, but Atala’s studies show scientists are getting ever closer to finding a technological solution to one of medicine’s greatest challenges. CLAIRE CAMERON
£
ON THE WEB
• In July, ace science writer Liz Kruesi launched her blog, Astrobeat, where she’ll tune in to the rhythms of the universe and tell the stories of those who are also listening. For her first post, Liz dives into one of her favorite topics: the perplexing black hole at the center of the Milky Way. Check out more of her unique takes on the cosmos at blogs.DiscoverMagazine.com/Astrobeat • Senior Editor Gemma Tarlach is Discover’s authority on dinosaurs — she’s obsessed over them since she was a little girl. So in addition to writing about Spinosaurus and serving up 20 things you didn’t know about any given topic, she’s also launched a new blog, called Dead Things. Gemma’s digging the dirt on the latest finds, from dinosaur fossils to relics of lost civilizations. Head over to blogs.DiscoverMagazine.com/Deadthings
12
DISCOVERMAGAZINE.COM
WAKE FOREST INSTITUTE FOR REGENERATIVE MEDICINE
The Discover blog network continues to grow.
Amazing price breakthrough!
How can a hearing aid that costs less than $200 be every bit as good as one that sells for $2,000 or more? The answer: Although tremendous strides have been made in Advanced Hearing Aid Technology, those cost reductions have not been passed on to you. Until now... The MDHearingAid PRO® uses the same kind of Advanced Hearing Aid Technology incorporated into hearing aids that cost thousands more at a small fraction of the price. Over 75,000 satisfied PRO customers agree: High quality FDA registered Hearing Aids don’t have to cost a fortune. The fact is, you don’t need to spend thousands for a medical-grade hearing aid. MDHearingAid PRO® gives you a sophisticated high-performance hearing aid that works right out of the box with no time-consuming “adjustment” appointments. You can contact a hearing specialist conveniently online or by phone—even after sale at no cost. No other company provides such extensive support. Now that you know... why pay more? TAKE ADVANTAGE OF OUR 45-DAY RISK-FREE TRIAL! Hearing is believing and we invite you to try this nearly invisible hearing aid with no annoying whistling or background noise for yourself. If you are not completely satisfied, simply return it within that time period for a 100% refund of your purchase price. PROUDLY ASSEMBLED IN THE FROM DOMESTIC & IMPORTED COMPONENTS
¸MDHearingAid was designed and
developed by a nationally recognized ENT doctor who continues to stand behind their products.
¸MDHearingAid has more than
100,000 satisfied customers.
¸
MDHearingAid offers affordable lowest-priced FDA-registered hearing aids designed and assembled in America and provides FREE after-sale expert support online or by phone.
SAVE 90% COMPARED TO TRADITIONAL HEARING AIDS
6 Reasons To Call Now!
1. Lowest-Priced FDA-Registered
Hearing Aid In America
2. Doctor Designed, Audiologist Tested 3. World-Class Components from the
U.S.A. and Europe 4. Free One-On-One After-Sale Support Online Or by Phone. 5. The Real Deal—Not an inferior Sound Amplifier
6. Free Batteries For One Year
Plus Free Shipping
BATTERIES INCLUDED!
Doctors and patients agree: “BEST QUALITY SOUND” “LOWEST AFFORDABLE PRICE” Incredible… “I was surprised to hear sounds I had forgotten existed – the crispness of the bells we use in Church, the splash of water running, the rich overtones in music. Thank you.” – Rev. John C. Life-Changing… “Thank you for making an affordable hearing aid so that people like me can again be part of conversations…” – Cathy C. Value-Packed… “I’m a physician and I know how much people spend on their health care. MDHearingAids are just as effective (if not more) than traditionally high-priced hearing aids.” – Dr. Chang
READY TO USE RIGHT OUT OF THE BOX!
Nearly Invisible
For the Lowest Price Call Today
800-617-8106 BUY A PAIR AND SAVE $40
CW35 FREE Batteries for 1 Year
Use Code Or Visit:
and get
Plus FREE Shipping
MDHearingAid.com BIG SOUND. TINY PRICE. © 2016
THE
CRUX
Ask Discover
INBOX Thank You “All in His Head,” from the June 2016 issue, peered into Einstein’s creative mind as he changed the rulebook of physics.
Some Killer Insight In the June 2016 issue, “The Psychopath & The Hare” looked at Robert Hare, who developed a widely used test to identify psychopaths. I have subscribed to Discover magazine almost from the time it was established, and have always enjoyed each issue. However, your last issue with the article on psychopathy has changed my life. I immediately got a copy of Kent Kiehl’s book The Psychopath Listener. I’ve read it twice. The second reading was to better understand how the work he has done — amassing an unbelievable amount of data, including fMRI records of psychopaths and nonpsychopaths of all ages — could help society. No question in my mind that this data will dramatically change our legal and prison systems to make them more evidence-based. A.J. San Jose, CA
DID YOU Honeybees might be getting their buzz from caffeine. A study KNOW?
14
DISCOVERMAGAZINE.COM
Are we any closer to understanding the root cause of gravity between objects with mass? Can we use our newly discovered knowledge of the Higgs boson or gravitational waves to perhaps negate mass or create/negate gravity?
— Jeff Lepler, Redford, Michigan
A
Sorry, Jeff, but scientists still don’t really know why gravity works. In a way, they’ve just barely figured out how it works. The Higgs boson discovery four years ago helped verify how objects acquired their mass, but that doesn’t shed much light on gravity itself. In the 17th century, Isaac Newton was the first to formally connect an apple falling toward Earth and Earth itself “falling” around the sun. The force behind both was gravity, and Newton understood it as just an attraction that grew stronger between two objects the more massive and the closer they were. Albert Einstein came along a few centuries later and provided an interpretation: According to his general theory of relativity, gravity is a property of space-time, the fabric of the universe. The more massive an object, the more it warps space-time, causing nearby objects to “fall” toward each other. If an object is massive enough, it can actually create detectable gravitational waves, or ripples in space-time, which scientists saw for the first time earlier this year. But gravity is also one of the universe’s four fundamental forces (the others being electromagnetism, and the strong and weak nuclear forces). Because the other forces use “force carrier particles” to impart the force onto other particles, for gravity to fit the model, all matter must emit gravitons, which physically embody gravity. Note, however, that gravitons are still theoretical. Trying to reconcile these different interpretations of gravity, and understand its true nature, are among the biggest unsolved problems of physics. But, alas, what we do know does suggest antigravity is impossible. BILL ANDREWS
£
published in Current Biology found a boost in foraging activity among bees that frequented plants with naturally occurring caffeine in their nectar.
Q
Visit DiscoverMagazine.com/Ask for more. To submit a question, email us at
[email protected]
TOP: MOPIC/SHUTTERSTOCK. BOTTOM: WILLIAM RITCHIE/SHUTTERSTOCK
Andy Berger’s article on Einstein’s thought experiments is brilliant! I haven’t encountered a clearer description since I was a little girl in the early ’50s, when my father would tell me about scientific principles and curiosities as bedtime stories. I went to sleep with visions of Einstein’s thought experiments, the redshift, photosynthesis, infinite regressions and so on dancing in my head. No, I didn’t go into science, but I have tried to pass on to my children and grandchildren a sense of wonder and curiosity about the natural world. Thank you, Andy Berger. Cia Gadd Alberta, Canada
Urgent: Special Summer Driving Notice
To some, sunglasses are a fashion accessory…
But When Driving, These Sunglasses May Save Your Life!
Studies by the National Highway Traffic Safety Administration (NHTSA) show that most (74%) of the crashes occurred on clear, sunny days
Drivers’ Alert: Driving can expose you to more dangerous glare than any sunny day at the beach can… do you know how to protect yourself?
T
he sun rises and sets at peak travel periods, during the early morning and afternoon rush hours and many drivers find themselves temporarily blinded while driving directly into the glare of the sun. Deadly accidents are regularly caused by such blinding glare with danger arising from reflected light off another vehicle, the pavement, or even from waxed and oily windshields that can make matters worse. Early morning dew can exacerbate this situation. Yet, motorists struggle on despite being blinded by the sun’s glare that can cause countless accidents every year. Not all sunglasses are created equal. Protecting your eyes is serious business. With all the fancy fashion frames out there it can be easy to overlook what really matters––the lenses. So we did our research and looked to the very best in optic innovation and technology. Sometimes it does take a rocket scientist. A NASA rocket scientist. Some ordinary sunglasses can obscure your vision by exposing your eyes to harmful UV rays, blue light, and reflective glare. They can also darken useful vision-enhancing light. But now, independent research conducted by scientists from NASA's Jet Propulsion Laboratory has brought forth ground-breaking technology to help protect human eyesight from the harmful effects of solar radiation
Eagle Eyes® Lens
simulation
Slip on a pair of Eagle Eyes® and everything instantly appears more vivid and sharp. You’ll immediately notice that your eyes are more comfortable and relaxed and you’ll feel no need to squint. The scientifically designed sunglasses are not just fashion accessories—they are necessary to protect your eyes from those harmful rays produced by the sun during peak driving times.
light. This superior lens technology was first discovered when NASA scientists looked to nature for a means to superior eye protection— specifically, by studying the eyes of eagles, known for their extreme visual acuity. This discovery resulted in what is now known as Eagle Eyes®. The Only Sunglass Technology Certified by the Space Foundation for UV and BlueLight Eye Protection.Eagle Eyes® features the most advanced eye protection technology ever created. The TriLenium® Lens Technology offers triple-filter polarization to block 99.9% UVA and UVB— plus the added benefit of blue-light eye protection. Eagle Eyes® is the only optic technology that has earned official recognition from the Space Certification Program for this remarkable technology. Now, that’s proven science-based protection. The finest optics: And buy one, get one FREE! Eagle Eyes® has the highest customer satisfaction of any item in our 20 year history. We are so excited for you to try the Eagle Eyes® breakthrough technology that we will give you a second pair of Eagle Eyes® Navigator™ Sunglasses FREE––a $99 value! That’s two pairs to protect your eyes with the best technology available for less than the price of one pair of traditional sunglasses. You get a pair of Navigators with stainless steel black frames and the other with stainless steel gold, plus one hard zipper case and one micro-fiber drawstring cleaning pouch are included. Keep one pair in your pocket and one in your car. Your satisfaction is 100% guaranteed. If you are not astounded with the Eagle Eyes® technology, enjoying clearer, sharper and more glare-free vision, simply return one pair within 60 days for a full refund of the purchase price.The other pair is yours to keep. No one else has such confidence in their optic technology.Don’t leave your eyes in the hands of fashion designers, entrust them to the best scientific minds on earth. Wear your Eagle Eyes® Navigators
Navigator™ Black Stainless Steel Sunglasses
Receive the Navigator™ Gold Sunglasses (a $99 value) FREE! just for trying the Navigator™ Black
Navigator™ Gold Stainless Steel Sunglasses
Certified EAGLE EYES® was developed from original NASA Optic technology and was recently inducted into the Space Foundation Technology Hall of Fame.
Fitons available for $39+S&H Black or TortoiseShell design
with absolute confidence, knowing your eyes are protected with technology that was born in space for the human race. Eagle Eyes® Navigator™ Sunglasses Offer Code Price $49 + S&P Save $50
PLUS receive the Navigator™ Gold absolutely FREE!—2 pairs for the price of one!
18003332045 Your Insider Offer Code: EEN͚͘͜03 You must use this insider offer code to get our special price.
Stauer
® 14101 Southcross Drive W., Dept. EEN͚͘͜03 Burnsville, Minnesota 55337
www.stauer.com Rating of A+
† Special price only for customers using the offer code versus the price on Stauer.com without your offer code.
Smart Luxuries—Surprising Prices ™
THE
CRUX
BOOKS UTOPIA IS CREEPY AND OTHER PROVOCATIONS By Nicholas Carr
THE HIDDEN LIFE OF TREES
It’s ironic that Carr, a Pulitzer Prize finalist, takes on modern life’s short attention spans and worship of the superficial in a series of essays, some barely a page and one merely a sentence. But, as the title promises, these are rapid-fire volleys of ideas deceptively designed to engage at a depth greater than 140 characters. By turns wry and revelatory, and occasionally maddening, Carr succeeds in shaking the reader out of screen-zombie complacency.
What They Feel, How They Communicate
SUN MOON EARTH
By Peter Wohlleben
Some hikers enjoy traveling through forests because trees don’t talk — but it turns out they do. Wohlleben, a forester by profession, blends years of personal experience with new research into how the organisms exchange information, react to threats and even raise their young. While the science is interesting, it’s Wohlleben’s gentle storytelling that makes the read such a pleasure. ALL REVIEWS BY GEMMA TARLACH
16
DISCOVERMAGAZINE.COM
OTHER PAGES WE’RE TURNING
SEEDS ON ICE Svalbard and the Global Seed Vault By Cary Fowler
Deep in Arctic Norway sits a collection of seeds from around the world, a stockpile of genetic diversity that’s fast disappearing from cultivation. Fowler, a key player in the banklike facility’s creation, uses stunning images of the site and its surrounding landscape as a springboard into bigger-picture issues, including the need for what some have called a “doomsday vault.” His tone is more hopeful than gloomy, however, in this fascinating look at a place few of us would otherwise visit.
HOW TO MAKE A SPACESHIP
The History of Solar Eclipses From Omens of Doom to Einstein and Exoplanets
A Band of Renegades, an Epic Race, and the Birth of Private Spaceflight
By Tyler Nordgren
By Julian Guthrie
When the moon clips our view of the sun or our own shadow blots out our satellite, we experience it with the benefit of millennia of knowledge. We know years in advance when an eclipse will happen, where on the planet it will be visible and, perhaps most importantly, that the world will not end because of it. Our ancestors were not so wellprepared. Astronomer and physicist Nordgren charts the path our species has taken from terror to scientific understanding, and he’s done it with wit and clarity.
Guthrie reveals the roots of the current space race among entrepreneurs in this fast-paced account of would-be rocket men chasing the $10 million XPRIZE, announced in 1996 but unclaimed until 2004.
GIANTS OF THE LOST WORLD Dinosaurs and Other Extinct Monsters of South America By Donald R. Prothero
From the horned and particularly hideous Carnotaurus of some 70 million years ago to more recent 200-pound, sabertoothed relatives of the possum, South America was home to some of evolution’s greatest oddities.
Affordable Hearing Aid Technology Only $299!*
F1 RYEAERE
A
B
(*Each when you buy a pair)
Learn about our great digital technology at an affordable price.
The Revolutionary HCX! Digital sound processing chip provides crystal clear sound and makes speech easier to understand with less feedback than old analog technology DƵůƟƉůĞŵĞŵŽƌLJƉƌŽŐƌĂŵƐadapt ƚŽŵŽƐƚůŝƐƚĞŶŝŶŐƐŝƚƵĂƟŽŶƐ Nearly invisible thin tube design >ŽŶŐůĂƐƟŶŐƐŝnjĞϭϯďĂƩĞƌŝĞƐĂŶĚĂ ůŽǁďĂƩĞƌLJǁĂƌŶŝŶŐ ϭϬďĂŶĚƐŽĨůĂLJĞƌĞĚŶŽŝƐĞƌĞĚƵĐƟŽŶ helps to emphasize voices while balancing out background noise 100% Money Back Guarantee
5 Star Reviews! dŚĞLJƌĞ&ĂŶƚĂƐƟĐ͊ “I just received my ,yŚĞĂƌŝŶŐĂŝĚƐĂŶĚƚŚĞLJĂƌĞĨĂŶƚĂƐƟĐ͘ ĚǀĂŶĐĞĚīŽƌĚĂďůĞŝƐĨĂƌƐƵƉĞƌŝŽƌĂŶĚ ĨĂƌŵŽƌĞĂīŽƌĚĂďůĞ͊͟ - Chuck D. tŽŶĚĞƌĨƵůŽŵƉĂŶLJ͊ ͞/ǁŝůůĚĞĮŶŝƚĞůLJ recommend your company to my ƉĂƟĞŶƚƐ͘͟- Dr. Arun P.
Su p p ly O f B at te ri es * F E
C
D
G A) Microphone B) Volume Control Wheel C) Program Button D) Long Lasting Battery E) Digital Signal Processor F) Receiver (Speaker) G) Sound Tube More Technical Information At: www.AdvancedHearing.com/D60
Digital Hearing Aid Technology... For Only $299!* All digital hearing aids work the same way. The microphone picks up the sound and sends an electrical signal to the digital signal processor. The digital signal processor is the “brains” of the hearing aid. It takes the sound it receives and adjusts the sound to amplify important ƐƉĞĞĐŚƐŽƵŶĚƐĂƐǁĞůůĂƐĮůƚĞƌŝŶŐŽƵƚƵŶǁĂŶƚĞĚŶŽŝƐĞ͘;dŽĞŶƐƵƌĞƚŚĞ best in quality, our digital processor is designed and manufactured right here in the United States͘ͿKŶĐĞƚŚĞƉƌŽĐĞƐƐŽƌŚĂƐĂŵƉůŝĮĞĚƚŚĞƐŽƵŶĚ͕ it is passed to the receiver;ĂůƐŽŬŶŽǁŶĂƐƚŚĞƐƉĞĂŬĞƌͿǁŚŝĐŚĞŵŝƚƐĂ ĐŽƌƌĞĐƚĞĚĂŶĚĂŵƉůŝĮĞĚƐŽƵŶĚƚŚƌŽƵŐŚƚŚĞsound tube into your ear. Most importantly, your new HCX hearing aids work at a ĨƌĂĐƟŽŶŽĨ the costŽĨŶĂŵĞͲďƌĂŶĚŚĞĂƌŝŶŐĂŝĚƐ͘/ŶĂĚĚŝƟŽŶƚŽƚŚĞƚĞĐŚŶŝĐĂů components of the hearing aid, you also have a volume control that ĐĂŶďĞŵŽĚŝĮĞĚǁŝƚŚĂůŝŐŚƚƚŽƵĐŚŽĨƚŚĞĮŶŐĞƌ͘zŽƵƌ new hearing aids come with ϯĚŝīĞƌĞŶƚĂƵĚŝŽƉƌŽŐƌĂŵƐ ƚŚĂƚŚĞůƉLJŽƵůŝƐƚĞŶŝŶĚŝīĞƌĞŶƚƐŽƵŶĚĞŶǀŝƌŽŶŵĞŶƚƐ͘ The zŽƵǁŝůůůŽǀĞƚŚĞKƉĞŶͲĮƚĚĞƐŝŐŶ͕ƚŚĂƚŝƐƐŽůŝŐŚƚLJŽƵ HCX probably won’t even feel that you are wearing your hearing aids – you’ll just be hearing clearly!
TM
zŽƵĐĂŶƐƉĞŶĚƚŚŽƵƐĂŶĚƐĨŽƌĂŚŝŐŚͲĞŶĚŚĞĂƌŝŶŐĂŝĚŽƌLJŽƵĐĂŶƐƉĞŶĚ just $329 for a hearing aid that just plain works (only $299 each when you buy a pair). We are so sure you will love our product, that we ŽīĞƌĂ100% Money Back Guarantee - Risk Free if you are not ƐĂƟƐĮĞĚĨŽƌĂŶLJƌĞĂƐŽŶ͘
,ĞĂƌĞƩĞƌtŝƚŚϮ,ĞĂƌŝŶŐŝĚƐ͊ zŽƵƌďƌĂŝŶŝƐĚĞƐŝŐŶĞĚƚŽƵƐĞďŽƚŚĞĂƌƐ working together to fully understand what you hear. In fact, studies show ƚŚĂƚLJŽƵŵĂLJďĞĂďůĞƚŽŚĞĂƌƵƉƚŽϯ ƟŵĞƐďĞƩĞƌŝŶŶŽŝƐLJƐŝƚƵĂƟŽŶƐǁŚĞŶ using two hearing aids.
BUY A PAIR AND SAVE $60 !
1-888-700-2152 *Free 1 Year Supply Of Batteries With Hearing Aid Order. Use Coupon Code: D60 (Coupon Code & Price Valid For A Limited Time Only)
The HCX
TM
Affordable Quality Since 1996!
US Company Owned And Operated
FDA
REGISTERED
Visit and Save: www.AdvancedHearing.com/D60
Prognosis
A Mind in Time An unprecedented view of one person’s brain function over many months could unlock new therapies. BY ADAM HADHAZY
Two mornings a week for the better part of an 18-month stretch, you could find Russell Poldrack with his head inside a giant metal doughnut — the business end of a magnetic resonance imager. As Poldrack lay still for 10 noisy minutes, the machine measured the activity throughout his brain’s neural networks. Roughly once-a-week blood draws followed, checking nutrient and gene expression levels in his body. In total, Poldrack racked up 104 gratingly loud brain scans. He got stuck by needles, oh, four dozen times. On top of all that probing and poking, he also kept frequent logs of diet, sleep and stress. Poldrack took the axiom “know thyself ” to obsessive new levels in the service of his MyConnectome project, the most intensive examination undertaken of a single living person’s brain. MyConnectome aims to plug gaps in the fundamental understanding of how activity varies in the human brain, across the 100 trillion interconnections of its 100 billion-odd neurons. One of these knowledge gaps is temporal. Scientists have studied brain changes on short terms of seconds and minutes, such as when research subjects complete a task, as well as on the long term of years, documenting cognitive decline during the aging process. But anything in between is unknown, essentially mentis incognita.
18
DISCOVERMAGAZINE.COM
“No one has ever looked at how the brain varies over the course of days, weeks and months,” says Poldrack, a psychologist and neuroscientist at Stanford University. A second gap is personal. Imaging studies — which for decades have revealed the brain regions behind our behaviors, appetites and mental disorders — have tended to lump together scans from a bunch of people, in the process overlooking individual cerebral variations. Studies have also largely assumed that measuring someone’s brain function at a point in time is generally representative of that person’s daily function at that point in life. That notion appears way off the mark, though, for people diagnosed with specific psychiatric disorders. For
example, those with schizophrenia may end up in weeks-long active phases of disease, experiencing hallucinations, delusions, even full-blown psychosis. Depression and bipolar disorder are other conditions that flare, then dissipate as the brain returns to an even keel. To open up new roads into treating these and other diseases, MyConnectome and studies like it are capturing a normal brain’s ebbs and flows. The approach should help make personalized medicine possible, tailored to each patient’s unique neural wiring diagram, or connectome. “If we want to understand fluctuations in disease, the first thing we need to do is to understand how a healthy person’s brain function fluctuates,” says Poldrack.
SIMONE GOLOB/GETTY IMAGES
→
CLOCKWISE FROM TOP LEFT: ALEXANDER WANG/THE UNIVERSITY OF TEXAS AT AUSTIN (3); POLDRACK, R. A. ET AL. LONG-TERM NEURAL AND PHYSIOLOGICAL PHENOTYPING OF A SINGLE HUMAN. NAT. COMMUN. 6:8885 DOI: 10.1038/NCOMMS9885 (2015), CREATIVE COMMONS 4.0
Neuroscientist Russell Poldrack undergoes one of 104 MRI scans at the University of Texas Imaging Research Center. At right, a slice of his brain is shown on a monitor.
TAKING THE PLUNGE Logistical roadblocks have long stymied the collection of brain-andbody fluctuations. What healthy person would want to report to a lab for frequent MRIs and jabs? And who would pay for the procedures? Those objections became moot for Poldrack several years ago, while at the University of Texas at Austin. A friend involved in the Quantified Self, a movement embracing technology for self-tracking, finally convinced him. “My friend was goading me,” says Poldrack. “She said, ‘You’ve got an MRI scanner in your basement. You’ve got to get in there!’ ” (Poldrack’s lab still had to pay for scans, but at an early-bird, pre-8 a.m. rate of $150 a go.) In subjecting himself to MyConnectome’s demands, Poldrack drew inspiration from numerous self-experimenting scientists. One such “human guinea pig,” Michael Snyder, is now a colleague at Stanford. In 2012, Snyder and his research team published a groundbreaking study in which they analyzed the levels of 40,000 molecules from 20 of Snyder’s own blood samples, taken over 14 months. The effort yielded the first “integrative personal-omics profile,” or iPOP, documenting Snyder’s unique set of active genes, metabolites, proteins and other biomolecules.
Tuesday: fasted, no caffeine
Thursday: fed, caffeinated
Data from Poldrack’s brain scans show changes in coordination between regions for movement control, attention and vision, as he shifted between states of being fasted and fed.
Snyder’s research goals were similar to Poldrack’s MyConnectome in pointing the way toward a precision kind of medicine, focusing on patients’ particular biochemistries, as opposed to today’s one-size-fits-most approach. “Snyder’s work made me think I can do interesting science with an n of 1,” says Poldrack, using the scientific jargon for a sample size consisting of just a single individual. MyConnectome was born.
SELF-EXAMINATION Although analysis continues for the massive pile of data gathered from September 2012 to March 2014 for MyConnectome — or the “Russome,” as Poldrack’s labmates call it — some intriguing correlations have already emerged.
Before his Tuesday MRI scans, Poldrack fasted and gave up his morning coffee. On those days, the scan revealed stronger signals of coordination between regions for somatomotor (which senses touch and controls movement), attention and vision. “These studies are a window into the brain-body connection,” says Poldrack. Also, the metabolic markers and levels of gene activity in Poldrack’s blood varied considerably with diet and brain function, as well as the severity of his psoriasis, an autoimmune disease that causes his scalp to flake. Another important finding was the fluctuating activity within certain regions in Poldrack’s brain, which stood out from the averaged pointin-time scans of multiple people used in conventional research. Those
October 2016 DISCOVER
19
Imaging studies that combine scans from many people, such as this diffusion image (above) from the Human Connectome Project, don’t identify brain variations in individuals. In contrast, Poldrack’s individual scan (right) shows an area in yellow, indicating an anomaly in his corpus callosum.
blended scans usually find the greatest difference in subjects’ prefrontal cortex, the seat of individual personality. Poldrack’s data suggests researchers are missing the even greater fluctuations in an individual’s other brain regions over time. That means data on potentially key differences within individuals — and their relation to wellness and illness — is getting lost in the wash, Poldrack says. Future studies could flesh out the significance of the “Russ-ome’s” idiosyncrasies by comparing them with the Human Connectome Project (HCP), which Poldrack has served on the advisory board of since it launched six years ago. This major international effort is pooling the snapshot scans of 1,200 individuals to create a generic, but authoritatively thorough, baseline brain map. “When we put the datasets side to side, there will likely be some interesting insights about how Russ’ brain and its structural organization relate to the hundreds of individuals we have charted,” says HCP neuroscientist David Van Essen of Washington University in St. Louis.
THE “ME” IN “MEDICINE” Numerous researchers are currently delving into Poldrack’s public datasets
20
DISCOVERMAGAZINE.COM
“The more we get, the more we learn, and we’re already learning that everyone’s baseline is different.” and have expressed interest in pursuing their own MyConnectome-style studies, this time involving multiple individuals. Stanford’s Snyder is pleased about the growing push to understand human biological variation via personal connectome and other “-ome” profiles, such as metabolomes (the total metabolites present at a given time in our bodies) and proteomes (ditto for proteins). “My own view about this is you can’t have enough of these profiles,” Snyder says. “The more we get, the more we learn, and we’re already learning that everyone’s baseline is different. People are poised very differently to respond to environmental cues.” Poldrack and Snyder hope that the vastly expanded and frequent testing they’ve tried to pioneer on themselves will help personalize medicine, leading to improved diagnoses and prognoses. “We’ll have a whole different world
where we’re measuring people in a lot more sensitive fashion,” says Snyder. His own experience is a telling one: During Snyder’s deep, inward look for the iPOP project, he witnessed himself in real-time unexpectedly develop Type II diabetes. He had none of the common risk factors and knew of no family history of diabetes. Thanks to the frequent monitoring, and catching the disease early, Snyder was able to respond and slow its progression. Poldrack is likewise hoping for further insight into the foods, mental states and other factors that exacerbate his psoriasis. As researchers tease out the daily goings-on of singular minds, perhaps millions of those with mental illness can hold out similar longings for relief as certain “triggers” of their conditions are identified. “Probably the best thing that can come out of [MyConnectome] is inspiring someone to go and do a really great job with a big population of people studied over a long period of time,” says Poldrack. “We want to answer the question of what’s going wrong in the brain and the body.” D Adam Hadhazy is a freelance science writer based in New Jersey. He writes for New Scientist and BBC Future, among other publications.
LEFT: DAVID SHATTUCK AND PAUL THOMPSON/HUMAN CONNECTOME PROJECT. RIGHT: POLDRACK, R. A. ET AL. LONG-TERM NEURAL AND PHYSIOLOGICAL PHENOTYPING OF A SINGLE HUMAN. NAT. COMMUN. 6:8885 DOI: 10.1038/NCOMMS9885 (2015), CREATIVE COMMONS 4.0
Prognosis
The incredible Five-Star Opal Anniversary Ring fulfills one of our long-held commitments, and celebrates yours.
1.5 total carats of genuine Ethiopian opal for under $100! PLUS, FREE matching earrings!
Add Some Wow toYour Vows Put a rainbow on her finger with the opal that’s taking the jewelry industry by storm.
L
ong ago, we made a vow: We would not produce a five-opal anniversary ring until two very specific conditions were met. First, the opals had to be of superior quality, with the joyous iridescence to delight all who saw the precious stone’s colors dance in the light. Second, the price had to be right, so that we could provide the value Stauer clients expect from us. So when The New York Times style section called Ethiopian opal the “undisputed winner” of the 2014 Gem Show, we decided to pounce. The result is the astoundingly beautiful Five-Star Opal Anniversary Ring. All five of these exotic beauties possess the radiant rainbow of color we’ve been looking for. Arranged in a sterling silver setting finished in lustrous gold, this ring is a beautiful tribute to your lasting love. So how about our price promise? We EXCLUSIVE met that too. We want you to know there is absolutely no reason to overpay for luxury gemstones. The big name jewelers have Five Star Opal been deceiving the public long enough, Stud Earrings charging as much as $16,000 for an -a $199 value- Ethiopian opal ring. We won’t trump up with purchase of the price to make you think it’s luxurious. Five Star Opal Ring This ring is just as luxurious (if not more) than the big designer name rings, AND it’s yours for under $100. I think it’s safe to say we more than met our price promise. We exceeded it... by about 16,000%!
FREE
“Opal’s spectacular play-of-color can display all the colors of the rainbow.” — Gemological Institute of America
“The play of color in opals is so gorgeous they sometimes don't even seem real and yet they are.” — from 2015 Couture Show Your satisfaction is 100% guaranteed. Slip this rainbow on her finger. If she’s not absolutely delighted simply send it back within 60 days for a complete refund of the sale price. The stud earrings are yours to keep. See if your jewelry store can match that! The FiveStar Opal Ring is one of Stauer’s fastest sellers. Supplies are limited. We can’t seem to keep this ring in stock. Don’t miss this rare opportunity. Plus, call today and receive the matching opal stud earrings FREE! You’ll want to catch this radiant rainbow before it’s gone!
FiveStar Opal Anniversary Ring $399 Offer Code Price Only $99 + S&P Save $300! Plus, FREE opal stud earrings, a $199 value You must use the insider offer code to get our special sale price.
18003332045 Your Insider Offer Code: OAR1͛͝01 Please use this code when you order to receive your discount.
Stauer
®
14101 Southcross Drive W., Dept. OAR1͛͝01, Burnsville, Minnesota 55337 www.stauer.com
Rating of A+
* Special price only for customers using the offer code versus the price on Stauer.com without your offer code.
1.5 ctw Ethiopian opal • Goldfinished .925 sterling silver setting • Whole ring sizes 5–10
Smar t Luxuries—Surprising Prices™
Mind Over Matter
Think Outside the Brain How our body can influence our mind. BY MALLORY LOCKLEAR
→
22
DISCOVERMAGAZINE.COM
In Shakespeare’s famous play, Lady Macbeth’s guilt over her role in a murder is so great that she imagines bloodstains on her hands and compulsively washes them. This phenomenon, called the Macbeth effect, ties into what scientists call embodied cognition.
Somehow, I hid that he was getting a monthly hot sauce subscription. I just attributed it to the oh-so-clever way I’d disguised my deception. But the motivation to suddenly brush my teeth may have been rooted in something much deeper: the Macbeth effect, named after the scene in the Shakespeare play where Lady Macbeth’s complicity in a murder leads her to imagine bloodstains on her hands. Her guilt makes her feel physically unclean even though she actually isn’t.
ABSOLUTION Studies have found Lady Macbeth’s reaction to be more than drama. For instance, researchers have shown hand-washing can assuage guilt
over past misdeeds. Similarly, after thinking about an unethical act, people tend to rate household cleaning products more highly. All of this has to do with something called embodied cognition, a relatively new idea asserting that as the mind influences the body, the body influences the mind. “Embodiment is very interesting because it’s a new way to do research on [sub]consciousness,” says neuroscientist Michael Schaefer at Medical School Berlin, “so we really can try to unravel things that we cannot see in a regular way.” Going beyond ethics, scientists have found that physical experiences influence other aspects of cognition, too. In 2014, researchers in Germany had people read an ambiguous
WORLD HISTORY ARCHIVE/ALAMY STOCK PHOTO
It was December, and my boyfriend and I were teasing each other about the gifts we’d gotten for one another. “Well, it’s a thing that I purchased from a store,” I said, washing my face as I got ready for bed. “It’s stuff in a box, but originally it was in a bag,” he responded from the other room. Fun, useless banter. But at some point, I got too specific. I told him one of his gifts was something I ordered, but the particular things would be a surprise to both of us when he opened it. As soon as I said it, I knew I’d given too much away — there were going to be follow-up questions. And what I did next felt strange, even as I was doing it. I stopped in the middle of my nightly ritual of moisturizing my face and started brushing my teeth instead. At the time, I thought maybe I switched to the toothbrush because lying to my boyfriend about his gift would be less obvious if my fibs were muffled and my face was partially obscured. “Is it some sort of subscription service?” With brushing sounds: “Mmmm, no.” (It was.) “Is it some kind of food thing?” I brushed harder, smothering awkward laughter: “Nooo.” (It was that, too.)
JESSICAHYDE/SHUTTERSTOCK
conversation while touching either a rough or smooth surface. When they touched the rough surface, participants were more likely to think the conversation was adversarial and harsh. And a 2010 Science study found that people tended to rate a job candidate more highly if the candidate’s résumé was attached to a heavy, rather than a light, clipboard. So my urgent need to brush my teeth as I steered my boyfriend away from discovering his gift may not have been a tool to mask my untruths. Instead, it might’ve been a personal need to absolve myself of guilt as I cleaned my lying mouth. As Schaefer tells me, “The Macbeth effect is very interesting because it describes a link between physical cleaning and moral purity. When you’ve done something bad to a person, like lie, you have the need to clean your body, and if you get to, you feel better.” This intrigued me, not only as a guilty, serial gift-liar, but also as a neuroscientist. And it has intrigued other neuroscientists and psychologists, too, such as Schaefer. In a study published last December, he and his team asked 35 participants to read various scenarios and then speak or write a prepared response that was either truthful or a lie. In one scenario, the volunteers found an important document that could hurt a colleague if they didn’t return it. Then the subjects told the colleague they did find it (the truth) or didn’t (a lie). Afterward, researchers showed the participants two products: a hand soap and a toothpaste or mouthwash. Then they asked them to rank each product’s desirability on a 4-point scale. Like previous studies, this one found that if participants lied, whether verbally or in a written note, they gave the hygiene products better scores than after telling the truth. If they spoke the lie instead of writing it, they rated toothpaste and mouthwash higher than hand soap (and vice versa.) So it seems
while people scored toothpaste and mouthwash products than it was after they told the truth.
In one study, people read a conversation while touching a smooth or rough surface. The chat seemed more hostile while touching the latter.
Going beyond ethics, scientists have found that physical experiences influence other aspects of cognition, too. people find cleaning the “dirty” part of their body — the part that commits the lie — more desirable than cleaning the “honest” parts. But connections between cleanliness and morality have been made before; Schaefer wanted to know what was happening in the brain. “The interesting thing is we have a map in our brain of our body,” he says. “So, everything on our body surface is represented in that map.” It’s called the somatosensory cortex, and it’s organized by body part. A touch on the foot would register in a certain part of the cortex, and a touch on the nose, another. Using fMRI, Schaefer and his team saw that when the study participants were rating hand-washing products, the part of their brains’ somatosensory cortex linked to the hand showed a flurry of activity. Surprisingly, that activity was much stronger after writing a lie than writing the truth. The same thing happened when they rated mouth-related products. After speaking a lie, the cortical area dedicated to their mouth was much more active
WARM FEELINGS Now I’m faced with a problem. If my boyfriend reads this, he might wise up to my own Macbeth effect, giving me away during future Christmas discussions. Maybe there’s some other Shakespearean-inspired psychological phenomenon to help me deal with my lies? Or maybe I’ll exploit the findings of another study. In a paper published in Social Cognitive and Affective Neuroscience in 2011, researchers at Yale described their discovery that people who touched a warm object were more likely to invest money with a stranger than people who touched something cold. And, like Schaefer’s study, the team observed the temperatureinfluenced trust effect in the brain, in an area known as the insula. Along with regulating other functions, the insula becomes more active when someone faces risk. When a participant held something cold before deciding whether to trust a stranger, the activity in the insula intensified. But when the participant held something warm, the insula remained in a calmer state. And a more relaxed insula is a more trusting insula. Turns out this warmth angle may actually be doubly useful for me. In a 2008 Science study, marketing professor Lawrence Williams and social psychologist John Bargh found that people were more likely to pick out a treat for themselves if they had recently held something cold. Yet when they’d held something hot, they were more apt to choose a gift for a friend. So maybe this December I’ll just manipulate my boyfriend’s insula and generosity with a warm cup of tea. What could go wrong? D Mallory Locklear is a science writer and has a Ph.D. in neuroscience.
October 2016 DISCOVER
23
Big Idea
Fighting Cancer With Data Doctors can now tailor cancer treatments based on their patients’ genes, but expansion will require new levels of data sharing and computing power. BY AIMEE SWARTZ
→
24
DISCOVERMAGAZINE.COM
The initiative enables cancer centers to access and analyze vast amounts of anonymous patient information — from genetic sequences and imaging data to findings in personal health records.
experimental drug homes in on the abnormal gene suspected to cause Dishman’s disease. Within three months of starting treatment, he was cancer-free and eligible for the kidney transplant that ultimately saved his life. Inspired by the treatment, Dishman is now on a campaign to make this kind of tailored cancer care available to more patients. And, ironically, this individually focused approach likely hinges on the efforts of crowds.
DATA-DRIVEN TREATMENTS The approach is already routine for some cancer patients, such as women and men with breast cancer tumors that have high levels of a protein called HER2, or lung cancer tumors
RA2STUDIO/SHUTTERSTOCK
Eric Dishman, a former Intel executive now at the National Institutes of Health, was a 19-yearold college sophomore when he was diagnosed with a rare form of kidney cancer. Over the course of the next 23 years, he would receive 62 different kinds of chemotherapy, immunotherapy and radiation. Some slowed the tumor’s growth, but never for long. The cancer spread from his left kidney to right kidney. Just when it seemed Dishman had run out of options, a chance encounter in 2012 with a scientist working for a now-defunct genometesting company presented an opportunity he couldn’t refuse. He had his cancerous tissue sequenced, a process that would compare his cancer’s mutated DNA with a healthy patient’s genome. This would let doctors look for genetic mutations and other abnormalities that support cancer growth, and to use that information to devise a treatment strategy. For example, changes in certain genes could indicate that his cancer was more likely to respond to a particular drug, while other mutations might predict little benefit from a specific therapy. Once the doctors sequenced his tumor, all he had to do was wait. And wait. Dishman says he was “literally at death’s door,” when he got the call from his doctor. It had taken seven months for a team of oncologists, computer scientists and data crunchers to analyze Dishman’s genetic data and pinpoint a drug — for pancreatic cancer — that would target the unique features of his cancer. This
FROM TOP: STEVE GSCHMEISSNER/SCIENCE SOURCE; CATHY CHENEY; OREGON HEALTH & SCIENCE UNIVERSITY
with mutations in the EGFR gene. These people can often benefit from drugs that target specific cancercausing aberrations rather than attacking the body as a whole. Most patients’ treatment trajectories are not as straightforward. In theory, insights into the genetic underpinnings of cancer, made possible through genomic sequencing, will allow people with even the hardest-totreat diagnoses to benefit from individualized treatment approaches. Currently, only about 2 percent of cancer patients have their genomes sequenced. These lucky few are most often treated at elite cancer institutions as part of a clinical trial. However, doctors are increasingly making use of the new technology as it becomes exponentially cheaper and faster. But devising treatment strategies based on insights from sequencing data, as was done for Dishman, requires “monumental shifts in how we share knowledge,” says Brian Druker, director of Oregon Health & Science University’s (OHSU) Knight Cancer Institute. First, it requires data, and lots of it. That’s the only way to pinpoint the mutations that cause cancers and fuel their growth. “Something that occurs in 1 in 5,000 people seems like a fluke. You really need a dataset of 500,000 or a million people to start seeing
Former Intel executive and cancer survivor Eric Dishman (above), now at NIH, wants to put vast cancer genome databases in the hands of doctors. The Knight Cancer Institute’s Brian Druker (right) leads one such high-profile effort.
This colored scanning electron micrograph shows a pancreatic cancer cell.
patterns,” Druker says. And second, it requires enormous computing power. Sequencing a single genome yields a terabyte or more of data; Dishman’s kidney tumor yielded 5 terabytes.
STRENGTH IN NUMBERS Druker and a growing number of scientists believe that amassing and deciphering this torrent of data requires the same open-source ethos that computer programmers have embraced to revolutionize software development. This approach makes the source code of a computer program openly available, and any improvements or modifications to the code are publicly shared. It could work with cancer, too. “Open source means that, rather than sharing code, scientists and clinicians share data and build upon each other’s knowledge,” says John Wilbanks of Sage Bionetworks, a non-profit biomedical research organization
in Seattle that supports open science projects. While few can dispute the benefits of accessibility — after all, scientists depend on the past research of others — Wilbanks says there’s a “prevailing data-hoarding culture.” Many scientists remain protective of career-advancing findings or intellectual property that could be commercialized. Others cite patient privacy concerns, particularly given the recent spate of data breaches within health care organizations. And data detached from names can still sometimes be used to identify supposedly anonymous patients. Even among those inclined to share, some practical challenges exist. Moving data from one institution to another can be expensive, and it can take weeks to ship hard drives or download the data. Few cancer centers have the resources to invest in powerful enough computers or robust enough networks to support the mammoth datasets. The result, says Dishman, is a “computational bottleneck that stymies progress.” It’s a bitter pill to swallow for an estimated 1.7 million people in the U.S. who will be diagnosed with cancer this year alone, especially for those with rare cancers. But they may soon have a new option.
QUICK CANCER QUERIES Intel and OHSU have teamed up through a new, open-source platform called the Collaborative Cancer Cloud (CCC). The initiative enables cancer centers to access and analyze vast amounts of anonymous patient information — from genetic sequences and imaging data to findings in personal health records. Unlike other open-source initiatives, which ask centers to transfer or retrieve data from one centralized location, the CCC allows researchers to keep their data local. Users access a virtual registry of all this data via
October 2016 DISCOVER
25
Big Idea
A GROWING MOVEMENT The CCC isn’t the only cloud-based data commons. The National Cancer Institute is developing a platform to house data from the Cancer Genome Atlas — a massive catalog of genomic data from over 11,000 cancer patients. And several institutions have their own clouds where cancer data is kept. “The problem is these clouds aren’t connected to other clouds. We want to connect them all because, really, we’ll not be able to find the root cause of cancers and the best treatments for those cancers without studying, literally, data from millions of patients,” says Dishman. So far, in addition to OHSU, the Dana-Farber Cancer Institute in Boston and the Ontario Institute for
26
DISCOVERMAGAZINE.COM
Killer T cells (green) surround a cancer cell (blue), where they will deliver the death blow via chemicals stored in vesicles (red).
“The idea is, you can blast a virtual query to sites around the world, who together have insight from a million other patients’ data, and ask, ‘Are there any patients that look like the patient in front of me on a genetic level?’ ” Cancer Research in Toronto have joined the CCC, and Dishman says “dozens of others” have expressed interest. Most cancer centers already have the necessary computing capabilities. “If they don’t, it’s as simple as downloading the CCC tools,” says Dishman. And while he expects many will run CCC on Intel servers, it’s not a requirement. “You don’t have to buy our products to be part of CCC,” says Dishman. “Because it’s open source, it can just as easily run on other computer architectures.” Druker says doctors can tap the
CCC to compare treatments and outcomes of similar patients in order to make the bestinformed decisions for the patient under their care. “The idea is, you can blast a virtual query to sites around the world, who together have insight from a million other patients’ data, and ask, ‘Are there any patients that look like the patient in front of me on a genetic level?’ ” says Druker. “ ‘And what treatments worked for them?’ ” Theoretically, the system would automatically return de-identified information about similar patients. Today, when Druker wants to gain insight from patient data beyond his own institution, he must do so manually, by phone or email. It’s a painstaking process that can take weeks or months. Though the CCC has just launched, its goal is to make this happen in less than a day by 2020 as more cancer centers join and share data. “You get sequenced in the morning,” says Druker. “Your data is then compared against millions of other patients. By the end of the day, your doctor can say, ‘Yes, we have found the treatment for you and the data to support that choice.’ “You can’t tell a patient to be patient. They need treatments today,” he added. D Aimee Swartz is a freelance writer based in Washington, D.C. She frequently covers health, with a focus on rare diseases and precision medicine.
ALEX RITTER, JENNIFER LIPPINCOTT SCHWARTZ AND GILLIAN GRIFFITHS/NATIONAL INSTITUTES OF HEALTH
the cloud — that is, a network of remote servers hosted on the internet, like the one where your email and selfies are stored. “With a simple query, you can remotely explore datasets held by institutions that have agreed to share their information,” says Dishman. Every query and answer is wrapped in an encrypted shell before being sent, so it is “completely secure and anonymous.” In addition, the CCC provides users with cloud-based access to a collection of tools commonly used for genomic analyses, which means centers don’t have to shell out for costly in-house hardware and analytics stacks. “Rather than ask people to move the data out, we bring the computer power in,” says Dishman.
Breakthrough Science for Curious Minds
SPACE
SCIENCE
ARCHAEOLOGY
THE YEAR IN SCIENCE
MEDICINE
Discover
Every issue of Discover magazine expands your horizons with:
TOP STORIES
• Compelling stories from the realms of health, mind, and medicine.
SCIENCE FOR THE CURIOUS
®
January/February 2016
100 OF 2015 Biggest SETI Search Ever Human Gene Editing
PLUTO SHINES A big year for
Limb Grown in a Lab The End of the Universe?
the little world.
. . . and More
Kennewick Man
New Dinosaurs
• The latest breakthroughs in science, technology, and space.
• Environmental issues and their impact on daily life.
Antibiotic Breakthrough
LHC Reboot
Wildfires!
• Insightful articles from award winners, opinion makers, and more.
New Species
Subscribe online at DiscoverMagazine.com P28091
MIND
Or call 800-829-9132
What it Takes to Reach... The secrets to staying young may lie in the DNA of the oldest among us. BY LINDA MARSA
“There are just two of us left now,” Jemima Westcott says wistfully. Only she and her kid brother, a sprig at age 94, remain of a oncethriving family. Westcott’s older sisters died at age 105 and 107, and she marked her own 105th birthday in January at a dinner party in her cozy condo in Brandon, Manitoba, surrounded by her children and grandchildren. Widowed for 50 years, she still lives alone, cooking and cleaning for herself — her only concession to old age is using a walker. Westcott has lived through iconic events of the 20th century. She has vivid memories of the celebrations when soldiers returned home from World War I; of big picnics on her family’s farm on the windswept prairies; of gas rationing during the second world war, when she was a young mother with five kids; and of traveling across Europe, North Africa and the U.S., and even diving in the Great Barrier Reef during a yearlong stint in Australia after she retired. “I’ve had an adventurous life,” says the former schoolteacher, an admitted night owl who stays up into the wee hours and
28
DISCOVERMAGAZINE.COM
likes to sleep in. Her secret to a long life? “Resilience.” Westcott may be on to something. She’s a participant in the New England Centenarian Study, a long-term research project at the Boston Medical Center that studies why people like her enjoy such exceptional longevity. What they’ve found, thus far, is that healthy habits and positive attitudes will only get you so far: Centenarians are winners of the genetic lottery and, like Westcott, have a clustering of long-lived relatives. They are remarkably intact mentally, and up to 90 percent of them can function independently into their ninth decade. Surviving past age 100 means they’ve largely evaded the scourges that kill their peers before they reach their 90s (what’s called compressed morbidity), or sidestepped the worst aspects of these life-threatening diseases — even if they strike sooner — because they have combinations of protective genes, what researchers call “greater functional reserves.” “Even though they have these illnesses, they handle them better than other people and
October 2016 DISCOVER
29
WILLIAM ZUBACK/DISCOVER; CANDLE ILLUSTRATION BY JAY SMITH
have better protective mechanisms,” says Thomas Perls, a geriatrician at Boston University and director of the New England Centenarian Study. “In other words, the older you get, the healthier you have been.” Now scientists like Perls are sifting through millions of DNA markers to spot the constellation of longevity genes that’s carried in every cell of these centenarians’ bodies. Perls and his colleagues have uncovered 281 genetic markers that seem to perform a protective function, slowing aging and making this group less vulnerable to disease. Other researchers, in sequencing the genome of centenarians, have found they possess fewer of the genes that contribute to major diseases. “They live longer, in part, because they don’t get sick,” says Stuart Kim, one of the study co-authors and a geneticist at Stanford University. How does this happen? Scientists suspect there may be some kind of intrinsic biological clock that runs slower in some people and quicker in
others, which would accelerate aging and wear down the body’s protective processes. Those with faster clocks are then more vulnerable to the onset of fatal diseases and die sooner. Research into the genetics of long-livers, and into other biological systems that may influence aging, offers some tantalizing clues into the underlying mechanics of these clocks. Deciphering precisely how
30
DISCOVERMAGAZINE.COM
they work could enable us to tinker with these internal timepieces and genuinely slow down the aging process.
REAL AGE Timing seems to be a key piece of the puzzle. Biological age doesn’t always match what’s on a person’s birth certificate. After all, we’re not surprised to see a 70-something debilitated by illness, or a 74-year-old who barnstorms around the country, running for president. Some people simply age faster than others, and scientists are beginning to understand why. New research using data from a landmark longitudinal study has been particularly eye opening. Known as the Dunedin study, it followed more than 1,000 people from their births in the early 1970s in the same hospital in southern New Zealand. Most research looks at aging in older people, but the seeds of agerelated diseases are planted decades earlier — that’s why these researchers
believe it’s crucial to study aging in the young. They aim to shed light on why we become vulnerable to the assaults of time and the chronic diseases linked to aging, such as cancer, heart disease, diabetes, and loss of mental acuity. Scientists in the U.S., U.K., Israel and New Zealand looking at the Dunedin data used it to track 18 biological measures, including liver and kidney function, blood sugar and cholesterol levels, balance, cognitive ability, cardiovascular fitness and even gum recession in 954 study participants. As expected, most people’s biological age clustered around their early 40s, within a few years of their actual ages, according to results released last year. But there were wide variations: A handful were up to a decade younger, while many had a biological age in their 50s; one participant had a biological age of 61. Even before midlife, some participants were aging much faster. They were already having trouble with
TIM SMITH
Scientists suspect there may be some kind of intrinsic biological clock that runs slower in some people and quicker in others, which would accelerate aging and wear down the body’s protective processes.
Jemima Westcott
climbing stairs and difficulties solving unfamiliar mental tasks, their balance was worse, their livers were starting to fail, and they were in poorer overall health. “When we assembled all the data, we were quite struck about the coordinated changes we did see in all the systems of the body,” says Daniel Belsky, the study’s lead author and a gerontologist at Duke University’s Center for Aging. “Clearly, there are basic molecular mechanisms of aging that cause the various diseases that disable and ultimately kill us.”
UNIVERSITY ARCHIVES PHOTOGRAPH COLLECTION/GEORGE A. SMATHERS LIBRARIES/UNIVERSITY OF FLORIDA
THE CELLULAR COUNTER More than 50 years ago, a researcher uncovered the first clues that an internal biological clock might regulate age — and that it’s not just the daily assaults from the external wear and tear of life that cause us to wither and eventually die. That’s when Leonard Hayflick discovered what would become known as the Hayflick limit. In the late 1950s, as a young microbiologist at the Wistar Institute in Philadelphia, Hayflick studied viruses that might cause cancer. While there, he worked with cell cultures derived from human fetal tissue. One day, the cell division in one of the
flasks seemed to be slowing down, and after about the 40th doubling, the cells stopped reproducing. At that time, scientists believed all cells were immortal — marinate them in the proper nutrients, and they would divide forever. Hayflick thought he had made a technical mistake or that the cells were contaminated. But then he observed the same halt in cell division in other cultures with different fetal tissues. He went back through his records, looking for clues to the anomaly, and discovered that of the many cultures he had made, it was always the oldest ones that had stopped replicating. While cancer cells are immortal — their hallmark is wildly reproducing out of control — Hayflick discovered that normal cells have a limited life span. Even when cells are frozen for months, subsequent research demonstrated, when they thaw out, they pick up their cell division where they left off until they hit between 40 and 60 doublings. “When I discovered that normal cells had a memory, I nearly fell of my chair. No one ever thought normal cells had a memory,” Hayflick recalls. “There had to be some sort of intracellular counting mechanism
Leonard Hayflick
or meter that tells the cells how many divisions it has gone through. But where?” In 1975, Hayflick and graduate student Woodring Wright proved the counting device was in the cell nucleus, but they didn’t have the technological tools to unlock the precise mechanism. Even though Hayflick’s discoveries went against accepted scientific dogma — “I was the first one to show that aging had its origins inside the cell,” he now says — they ultimately sparked an explosion in the study of aging. But another decade would pass before a candidate emerged for Hayflick’s “replicometer.”
DNA FRAGMENTS Despite all the accolades heaped upon her for groundbreaking research, Elizabeth Blackburn retains the homespun warmth, sharp wit and
At the time, scientists believed all cells were immortal — marinate them in the proper nutrients, and they would divide forever. plucky spirit of her native Australia. Early this year, the Nobel Prizewinning biochemist left her lab at the University of California, San Francisco, to head up the Salk Institute, the scientific incubator founded by polio vaccine pioneer Jonas Salk. The center is housed in a cluster of modern concrete and glass buildings perched on the coast in La Jolla, Calif. We sit at a conference table in her airy office, with floor-to-ceiling windows looking out on the Pacific. Blackburn, who hails from Tasmania, an island off the coast of Australia, earned her doctorate degree in molecular biology from the University of Cambridge in England. In the 1970s she landed at Yale
October 2016 DISCOVER
31
University, where she sequenced the tips of chromosomes of a single-celled organism, Tetrahymena — “pond scum,” she cheerfully offers. These tiny strips of DNA, called telomeres, cap the end of chromosomes. Scientists long suspected they stabilized the structure of the chromosome, preventing the tips from fraying, much like the plastic sheaths at the ends of shoelaces to prevent them from unraveling. But how? Each time a cell divides, the telomere gets shorter, but its function had long been unclear. “We had the seeds of an idea [that] there could be a clocklike thing, because every time the DNA replicated, the end of the chromosome wasn’t replicated,” Blackburn recalls. It wasn’t until the late 1980s that a strong connection was made between telomeres and cellular aging, in a breakthrough that resulted from a bit of scientific serendipity. Blackburn’s former graduate student, Carol Greider, was dating a biologist who shared lab space with Calvin Harley, a biochemist studying aging at McMaster University in Ontario. Casual conversations in the lab grew into a full-scale collaboration that melded Harley and Greider’s
areas of expertise — cell senescence and telomeres. The result was two landmark papers published in 1990 and 1992 that made a convincing case that telomeres might be the cellular timing device behind the Hayflick limit. With each cell division, telomeres dwindle until they are just tiny nubs, which prompt cells to malfunction, stop replication and finally die off. This research provided “some good clues that we were going in the right direction,” says Blackburn, “but it took years and years of observations by lots of scientists before the puzzle pieces were put together to form a real picture of what happens.”
STUNTED TELOMERES Telomere shortening is now considered a biomarker of cellular aging, and more evidence suggests that these tiny fragments of DNA may be one of the culprits behind age-related decline. Subsequent studies have shown that shortened telomeres are linked to many age-related diseases, including heart disease, diabetes, Alzheimer’s, stroke and obstructive lung disease. “These are the major killers of the elderly,” says Blackburn. “We’re starting to go
beyond just correlations and seeing a real element of causality here.” Even chronic stress can wear away our telomeres, according to research done in the early 2000s that looked at mothers caring for children with chronic diseases. Blackburn and UCSF psychologist Elissa Epel’s work found that the most stressed-out women had shorter telomeres that translated into an extra decade or so of aging compared with their matched controls — showing that external stressors can throw a monkey wrench into the cell’s molecular mechanics. More recent research, presented at a scientific meeting in 2012, analyzed saliva samples from more than 100,000 people who belonged to Kaiser Permanente, an HMO in Northern California. The major take-home message: People with stunted telomeres die at younger ages. What was equally intriguing is that even though women outlive men, as young adults their telomeres are about the same length. While everyone’s telomeres dwindle as they grow older, a big split occurs after age 50, when telomere shortening among men accelerates. The gender division continues to widen until about
TELOMERES AND AGING Elizabeth Blackburn talks about the link. Telomeres are tiny fragments of DNA at the end of each chromosome. Nobel laureate Elizabeth Blackburn has spent her career studying their function. Here, she talks about the role they play in aging. DISCOVER: Are telomeres the clock behind aging? BLACKBURN: As a loose approximation, aging is clocklike because there’s a progressiveness to it. But we’ve got to be smarter about what that word aging really means. Is human aging your risk of getting the diseases of aging? Well, in that case,
32
DISCOVERMAGAZINE.COM
centenarians never age. And yet, they clearly do age: They get wrinkled and frail and smaller — they’re doing well but they’re not young people. Aging has multiple aspects, and we tend to oversimplify it. A lot of different kinds of things come into play in different stages. If we avoid all the major diseases, there’ll still be an aging process, which is not identical. Telomere shortening seems to underlie the risks for the diseases that kill you. DISCOVER: In what way? BLACKBURN: Every sign,
Elizabeth Blackburn
including genetics, says there’s some causality [between telomeres] and the nasty things that happen
with aging, the really nasty diseases that kill us — heart disease, diabetes, cancer, even Alzheimer’s. We know
What We Lose With Age chromosome
cell
As cells divide over time . . .
telomeres
DNA
TOP: GWEN SHOCKEY/SCIENCE SOURCE. BOTTOM: JANERIK HENRIKSSON/AFP/GETTY IMAGES
. . . telomeres shorten, and eventually cell division stops.
telomere shortening drives cells into senescence [aging]. If you look at people with wrinkled skin versus not wrinkled skin, the people with sagging, UV-damaged skin have shorter telomeres than people with smooth, unwrinkled skin. If you’re in the bottom third of telomere length, your cardiovascular disease risk goes up 40 percent, which is not a trivial number. Pessimism correlates with shorter telomeres. So you can put all this together and say it’s reasonable that some of this is really driving pathologies in humans. DISCOVER: So the shorter the telomeres, the more likely it is
age 75, when those with the blunted telomeres die from disease. These results demonstrate at a molecular level what scientists tracking centenarians had observed: Longer-lived people have a biological advantage that enables them to escape or better withstand what Blackburn calls “the hail of bullets” that kill the majority of us. “Most mortality in the population happens around age 75, and anybody who lives longer has been somehow biologically selected,” says Blackburn. “We know telomere shortening drives cells into senescence. So it is reasonable to say that this is driving pathologies in humans.” But telomeres aren’t the whole story.
THE EPIGENETIC CLOCK “There’s a knot in here that’s going to give you trouble,” Jose Valencia warns me, speaking in Spanish through an interpreter while he massages the fleshy pad of skin between my left thumb and index finger, then flashes a mischievous, toothy grin, as if to tell me I’d better be careful. Barely 5 feet tall and clad in crisp khakis and a short-sleeve striped shirt, Valencia sits placidly on a bench in front of
you’ll be stricken with diseases and that you’ll age faster? BLACKBURN: If you inherit very short telomeres, you get this terrible disease now being called the “telomere syndrome.” It’s extremely rare because these poor children don’t survive into adulthood. But because there are billions of us on the planet, it’s happened often enough that there are now hundreds of individuals and many afflicted families around the world. A child will come into the clinic with a skin disorder, but that’s not the real problem: They have terrible gut disorders and their whole body is fraught with problems,
the cinderblock house he shares with his granddaughter, Keren Gonzales Valencia, in El Torito, Costa Rica, a tiny village honeycombed by dirt roads where the rainforest meets the beach. It is a sultry November day with temperatures hovering in the low 90s. It’s the end of the rainy season on the Nicoya Peninsula in the northwest corner of Costa Rica, and the jungle is lush from months of torrential downpours. A healer of local renown, Valencia taught himself anatomy by dissecting chickens — three of which lazily strut across the yard while we talk. He massages strained muscles and fixes dislocated joints when doctors are too busy, he says. Even the local expat surfers and retirees come see him when their backs hurt. A farmer all his life, Valencia retired at age 80 when he was diagnosed with leukemia, but it barely slowed him down. He’ll be celebrating his 97th birthday in a few days, he tells me, and shares bittersweet recollections of being a lovesick teenager eight decades earlier: There were no roads, and the only way he could visit his sweetheart in the next town was to walk along the beach. He attributes his long life
and they have this whole spectrum of very nasty, very early onset diseases, which are the ones that often appear with age. About 10 percent of them die of some rare cancer, and a lot of them die of infections, and their guts don’t work properly and they’re really sickly. But then you look at the parents and the grandparents because this gene has to come from somewhere. And you find the grandparent with the gene had pulmonary fibrosis. So the molecular cause is exactly the same base pair change in a telomerase gene. But it played out in the body
differently. The grandparent’s telomeres were shorter than their peers’ and the parent’s telomeres were even shorter, and the child’s were really short. So what if people inherited somewhat shorter telomeres and never completely recovered or do things that we know externally promote shortening of telomeres, like smoking or living in stressful situations? They might do just fine, but if there’s something else going on combined with the shorter telomeres, that might be enough to kill them. Telomeres are not the end of the story, but they play a role. — L.M.
October 2016 DISCOVER
33
to hard work, good food and family — his wife died less than a year ago and his extended family of children, grandkids and great-grandkids all live nearby. But his longevity is not unusual for the Nicoya Peninsula, an 85-mile sliver of pristine beaches, cow pastures, farms and wooded hills, where residents often reach ages of 90, 100 or even 110. Despite their poverty, locals live far longer than their wealthier counterparts elsewhere. The peninsula is one of the world’s five Blue Zones, where more people live past 100 than in other parts of the world. The other four longevity hot spots are Okinawa, Japan; Loma Linda, Calif.; Sardinia, Italy; and Ikaria, Greece. In 2005, Costa Rican demographer Luis Rosero-Bixby found that Costa Ricans who survive to age 60 end up having the longest life
expectancy of anyone in the world. Subsequent research in 2012 found that older residents of Nicoya lived even longer, up to three years more than other Costa Ricans. In research published in 2013, Stanford University epidemiologist David Rehkopf and his colleagues wanted to find out why. They took DNA samples from Nicoya residents who were older than 60 to measure the length of their telomeres. They turned out to be longer than those of other Costa Ricans, with an average difference of about 81 base pairs, equivalent to the benefits of
34
DISCOVERMAGAZINE.COM
Jose Valencia
quitting smoking or getting regular physical activity. Why do those on the Nicoya Peninsula live so long? The key seems to be in the nation’s familiar catchphrase: pura vida, or “pure life.” Costa Rica, a centuries-old democracy with universal health care, no standing army and the highest literacy rate in Central America, has been relatively insulated from the corruption, narco-terrorism and civil wars that have plagued neighbors like Panama, Nicaragua and Guatemala. Researchers believe Nicoyans’ leisurely pace of life, plant-based diet, network of family and friends, regular exercise and purposeful lives seem to be their recipe for longevity. While outside forces — stress,
poverty, environmental toxins — can accelerate aging, the reverse seems to be true, too. Our life experiences exert a profound influence on how we age and can even alter the ways genes function without changing the underlying DNA sequence; these genetic changes are called epigenetic traits. A research team at UCLA led by biostatistician Steven Horvath has uncovered an epigenetic biological clock that may provide a key puzzle piece in deciphering how this happens — and help explain why Nicoyans live so long. “For those people who age more slowly, somehow their epigenetic clock ticks more slowly,” Horvath says. “There’s an intrinsic process that drives aging, and that may be what’s captured by this epigenetic clock.”
LINDA MARSA
Our life experiences exert a profound influence on how we age and can alter the ways genes function without changing the underlying DNA sequence; these genetic changes are called epigenetic traits.
Loma Linda, California
Sardinia, Italy
Ikaria, Greece
Okinawa, Japan
Nicoya, Costa Rica
Blue Zones Longevity hot spots
FROM TOP: ILDOGESTO/SHUTTERSTOCK; UCLA
across the globe.
THE MECHANICS OF AGING For the German-born Horvath, a boyish 48-year-old with broad features and a puckish sense of humor, the discovery is the fruition of a lifelong dream, dating back to high school, when he decided to devote his career to prolonging the human life span. But it wasn’t until 2006 that the advent of big data allowed him to sift through millions of data points to ferret out biomarkers that correlated with age. His team focused on a naturally occurring process that’s part of the body’s internal housekeeping system, called methylation, which makes chemical modifications to our genome that are strongly influenced by environmental factors. Horvath was able to obtain over 50 datasets — from researchers in Spain, Germany, Italy, the U.S., U.K. and Australia — that contained the genetic profiles of thousands of subjects in studies looking at methylations in healthy tissue. Over the course of three years, Horvath and his team analyzed nearly 8,000 tissue samples from these datasets, which included blood, saliva and cells from organs like the brain and the colon. The UCLA team identified 353 DNA markers from 51 types of cells and tissues and examined how age affects their DNA methylation levels throughout a lifetime. They then used the data to devise an algorithm that can accurately determine the age of diverse organs, tissues and cell types.
When they compared a tissue’s biological age and its chronological age, the clock proved to be remarkably accurate in predicting age. Stem cells plucked from embryos were deemed extremely young by the clock, while neural cells from centenarians were estimated to be about 100. And even cells that were young, such as white blood cells that may be just a few days or weeks old, still carried the distinct genetic imprint of their 50-year-old donor. “The 353 markers on the DNA provide a weighted average that gives you a very accurate measure of the age of the tissue,” says Horvath. Since then, he has used the epigenetic clock as a tool to begin to understand the mechanics of aging. Subsequent research on Italian centenarians revealed that the offspring of these centenarians
Steven Horvath
were substantially younger, up to about five years, according to their epigenetic clocks, than the progeny of non-centenarians. But perhaps Horvath’s most significant finding had its genesis in 2013, when researchers from the Los Angeles Gerontology Research Group, which studies supercentenarians (those who live to 110 and older), supplied him with tissue samples from three centenarians and three supercentenarians, one of whom recently died at age 112. What Horvath uncovered was astonishing — and may eventually lead the way to extending our life. The research team analyzed the epigenetic age of up to 30 anatomic sites from the 112-year-old woman. They discovered that the cerebellum is the youngest part of the body and didn’t age nearly as fast as other areas. The neuronpacked brain region — it’s tucked underneath the cerebral hemispheres and plays a role in motor control and cognitive functions, such as attention and language — seemed to stop aging at the 80-year benchmark, which meant it remained fully functional but somehow impervious to deterioration of time for decades. Earlier this year, Horvath and his colleagues took a step toward answering this question. Their analysis uncovered small variations in two genes related to the accelerated aging of the cerebellum. What was especially “exciting” about this finding, he says, is that these variations were near a neural highway that previous studies have shown helps regulate life span in worms and flies, and that stopping chemical signals from this brain pathway extends the life span of mice. While this discovery is still not a “smoking gun,” says Horvath, “if we can understand why the cerebellum ages more slowly, we can figure out how to slow down all the other parts and uncover interventions that might be able to reverse this process.” D Linda Marsa is a Discover contributing editor and author of Fevered: How a Hotter Planet Will Hurt Our Health and How We Can Save Ourselves.
October 2016 DISCOVER
35
EARL MILLER sees the prefrontal cortex — home to working memory — as a switch operator working the brain’s railroad tracks.
36
DISCOVERMAGAZINE.COM
YOUR ATTENTION, PLEASE MIT neuroscientist Earl Miller has
changed the way we think about
working memory — the brain’s scratchpad.
He hopes to make us all smarter someday.
BY ADAM PIORE PORTRAIT BY JASON GROW
October 2016 DISCOVER
37
A STUDY IN CONTRASTS, Earl Miller plays bass at the Tavern at the End of the World in Boston’s Charleston neighborhood.
38
The jarring contrast between the two Earl Millers is a fitting way to begin a discussion of the pioneering neuroscientist’s work. After all, some of Miller’s biggest contributions to the field over the past 20 years have explored exactly how contrasts like these are possible; how it is, in other words, that human beings — or any other animal with a brain — are able to seamlessly adapt behavior to changing rules and environments. How is it that distinct populations of brain cells, or neurons, are able to work together to quickly summon an appropriate response? How do we know when it’s fitting to play a Patti Smith bass line, and when it’s time to explain the complex workings of brain waves? This mental flexibility is so fundamental that it’s easy to take it for granted. But there are few functions the brain must perform that are more
DISCOVERMAGAZINE.COM
complex or crucial to survival than recognizing when something has changed and then calling up all the disparate information needed to adapt appropriately. “Think about what we’re doing here,” Miller says. “Right now. We’re sitting on chairs. We’re taking turns talking. This is based on rules. We’ve learned how to behave in this context we’re in right now.” To pull off tasks like these, the brain uses something called working memory. Cognitive psychologists coined the term in 1960 as they tried to explain the fundamental structure of the human thought process. You can think of working memory as the brain’s conscious mental scratchpad — the chalkboard for attention and decision-making. Try to hold that last sentence in your mind, or memorize a phone number you’re about to dial, and you’ll have
engaged this critical brain system. Miller has spent the past two decades trying to understand the mechanisms behind working memory, and he believes the key lies in the brain’s prefrontal cortex. Insights into this thin layer of neurons at the front of the brain could answer questions that have flummoxed scientists for generations. It might have practical use, too. Experts have long known that we have a virtually unlimited capacity to store new long-term memories. Yet there’s a limit on how much information we can cram into our working memory. In studying the prefrontal cortex’s functions, Miller and others are coming closer to finally explaining this contradiction. And by solving this riddle, we may find ways to get beyond those limits. Someday, Miller believes, he’ll be able to make us all smarter.
JASON GROW
I
n the rehearsal space of the Boston band What She Said, Earl Miller lays into his bass guitar, plucking out a funky groove. He sticks out his tongue Mick Jagger style, as the band’s drummer hammers away behind him, clowning it up for photos splashed onto social media. In a black band tee, faded cargo pants and signature newsboy cap, Miller looks like a seasoned musician you’d see in any corner dive bar. But at his nearby office at MIT, Miller is nothing if not professorial. How could that rocker in the cap be the same bookish academic now gazing solemnly at me across his paper-strewn desk at the Picower Institute for Learning and Memory?
BRAIN: SCOTT CAMAZINE AND SUE TRAINOR/SCIENCE SOURCE; BACKGROUND: WATCHARA/SHUTTERSTOCK
BUILDING THE PICTURE cortex after a unified picture emerges? How do our Much of what we know about how neurons allow brains tell us what it means? animals to make sense of their surroundings began Miller tried to answer those questions while working in the lab of National Institute of Mental Health with experiments performed on the visual cortex neuroscientist Bob Desimone. Miller was looking of animals by David Hubel and Torsten Wiesel. As for neurons that fired only when an animal spotted postdoctoral students at Baltimore’s Johns Hopkins an item it was storing in short-term memory. Miller University in the 1960s, they set out to solve a longand Desimone trained animals to hold a single standing mystery: What happens in the brain when image in mind — such as an apple — and release a we see objects and shapes? lever when that picture reappeared on a screen. Every one of us has about 100 billion neurons, If the animal remembered the first picture it saw separated by gaps called synapses. Neurons talk to and released the lever, a drop of delicious juice each other by passing signals across these spaces. When one neuron’s signal is strong enough, it causes the neuron on the Experts have long known that we have a other side of the synapse to fire an virtually unlimited capacity to store new longelectrical spike. When that second neuron fires, it passes messages to all the term memories. Yet there’s a limit on how much other neurons it’s connected to, which information we can cram into our working memory. can cause those neurons to fire. This sequential firing of neurons allows us to think, to move — and to see. Hubel and Wiesel inserted tiny, pin-shaped microelectrodes directly into a cat’s visual cortex to measure the activity there. By projecting angled lines onto the surface of the animal’s retina, they demonstrated that each neuron in this thin sheet at the back of the head has a distinct function. Some fired with the greatest intensity in response to lines at specific angles, while others fired at angled lines moving in a specific direction. It is the consecutive firing of these individual, specialized neurons, each responsible for a specific detail in a picture or pattern, they argued, that helps us build complex images in our mind’s eye. Their work was so impressive within the field that it earned them the Nobel Prize in Physiology or Medicine in 1981. As it happened, Miller entered college at Kent THE PREFRONTAL State University the same year — though back then, CORTEX, highMiller dreamed of becoming a doctor. would roll down a tube and into its cage. lighted here That quickly changed when he started working in The pair noticed that certain parts of the animal in an MRI scan, plays a crucial a neuroscience lab. brain were inherently sensitive to repetition — role in working “The moment I first dropped an electrode into regardless of whether it translated into a valued memory — the chalkboard a slice of brain and heard all these neurons juice reward. Some neurons fired when animals saw brain’s for attention and firing away like a thunderstorm, I was hooked,” a second banana or second image of trees. It was decision-making. Miller recalls. as if the brain was on automatic pilot, primed to As a Princeton University graduate student, notice repetition without any active effort to do so, Miller studied the inferior temporal cortex, a patch even when that repetition had no meaning. of neurons slightly forward of the visual cortex. But the pair also discovered a second type of Scientists had demonstrated this was the region that firing pattern. When the animal spotted a picture it knits together a unified image from all the complex was actively holding in his memory — hoping for a individual components Hubel and Wiesel identijuice reward — not only did different neurons fire, fied. Then it starts the “higher level” processing of those neurons fired far more intensely. the outside world. “Something was switching the volume to make By the time Miller earned his Ph.D. in 1990, he these neurons fire, more or less, depending on the was asking the questions that would later define nature of the memory,” Miller says. “That got me his career: What happens in the inferior temporal wondering. Who’s turning up or down the volume?”
October 2016 DISCOVER
39
40
number of possible responses by adding a second cue. In between the first picture and those that followed, he provided a prompt, such as a low tone or a high tone. Then he showed the same picture again, this time next to a second picture. The high tone signified the animal should try to remember and choose that same first picture whenever it reappeared. But the low tone indicated the animal was to remember and choose the second picture, and ignore the first. Correct guesses resulted in the delivery of a tasty food pellet. Miller predicted he’d detect activity in multiple neurons in the prefrontal cortex every time he changed the rule. These neurons, he believed, somehow turned up or down the “volume” of the neurons
So, when Miller started his own lab at MIT in 1995, he decided to switch his focus to the prefrontal cortex. By then, some of his peers had already shown that clusters of neurons in lab animals would fire repeatedly in the prefrontal cortex during memory exercises. Their results suggested this region houses our working memory. To Miller, however, this didn’t explain how the executive areas of the brain could “turn up the volume” on memories associated with free juice. How does the animal know how to do the task? How does the animal know the rules? “I thought that was the most important thing,” Miller says. “I didn’t understand why no one was studying it. Context-dependent behavior is what high-level cognition is all about.” In his new lab, Miller designed an experiment that complicated the choice his animals faced. Instead of just showing an animal a picture and training it to respond every time it reappeared, Miller varied the
he’d recorded in other areas of the brain. Not only was Miller right, but the rule change consistently caused twice as many neurons in the prefrontal cortex to fire than in the more simplistic experiments where the task required the animal to just hold a picture in mind. “That told us something,” he says. Perhaps the prefrontal cortex’s primary job wasn’t short-term memory at all, but to learn the rules of the game. In 2001, Miller published a research review that fundamentally shifted the way many viewed the prefrontal cortex. Miller compared the prefrontal cortex to a railroad switch operator, and the rest of the brain to railroad tracks. The switch operator activates some parts of the track and takes others offline. This model would explain how attention works. It explains, for instance, how an animal can focus on a picture while suppressing a noise. And it explained why Phineas Gage had trouble blocking out distractions and focusing on the task at hand.
DISCOVERMAGAZINE.COM
LEFT: EVERETT COLLECTION/ALAMY STOCK PHOTO. RIGHT: FROM THE COLLECTION OF JACK AND BEVERLY WILGUS
PHINEAS GAGE (1823-1860) revolutionized neuroscience after an iron rod pierced the railroad worker’s frontal lobe. He recovered physically, but his personality was never the same.
TURN IT UP Scientists have suspected that the prefrontal cortex plays a key role in high-level cognition since the case of Phineas Gage. On Sept. 13, 1848, Gage, who worked in railroad construction, was setting an explosive charge with a tamping iron when the gunpowder detonated, rocketing a metal rod up through the roof of his mouth, into his left frontal lobe and through the top of his skull. The rod landed 75 feet away, coated in pieces of Gage’s brain. Miraculously, Gage survived and could speak, walk and function. But, it was written later, he could no longer stick to plans and lost much of his social grace and restraint. From studying Gage and others like him, neuroscientists surmised that the frontal lobes performed the brain’s “executive functions.” They run the business of thinking and processing and directing the spotlight of attention. And yet, nearly 150 years after Gage’s famous injury, scientists were still trying to understand how the frontal lobe works.
DAVID SCHARF/SCIENCE SOURCE
The theory made intuitive sense. But to some single wave can only rise and fall a certain number steeped in the specialized-neuron theories of Hubel of times a second. and Wiesel, Miller’s theory seemed preposterous. “That means you have to fit in everything you “That’s impossible!” Miller recalls one prominent want to juggle in your current conscious mind,” he neuroscientist declaring after Miller delivered an says. “That’s a natural limitation in bandwidth.” invited lecture. “We all know that neurons do one Brad Postle, a University of Wisconsin-Madison thing. Your problem is you can’t figure out what neuroscientist, says the idea that something other these neurons are doing,” the researcher told him. than the spiking of neurons is important has But Miller has continued to accumulate experibeen “kicking around for a while.” Postle himself mental evidence — as have many other labs — suggested brain waves may play a role in focusing gradually winning scientists over to his idea. attention. Still, he believes it’s significant that Miller “Neurons are multitaskers,” Miller says. “We’ve is now arguing the point. shown this over and over again for 20 years.” “Having it come out of Earl Miller’s mouth The important neurons, according to Miller’s almost by definition will bring attention to it,” says collaborator Stefano Fusi, a theoretical neurosciPostle, who authored a widely used neuroscience entist at Columbia University, are the flexible ones. textbook that includes many of Miller’s earlier Scientists expect they’re the majority in the prefronexperiments. “Earl is kind of a rock star. When he tal cortex, he explains. Otherwise an animal encountering a complex These days, Miller is taking on another piece of dogma — task would run out of neurons to that neurons primarily communicate by electrical spikes. make sense of it.
WAVE CHANGE These days, Miller is taking on another piece of dogma — that neurons primarily communicate by electrical spikes. In recent papers, Miller argues that there’s still a lot to learn from the intermittent electrical currents called oscillations, or brain waves. When we hold an item in working memory, these oscillations move through brain circuits in waves that rise and fall scores of times. These oscillations, he argues, are how the prefrontal cortex — that mental “switch operator” — stores several items on the cusp of our awareness in working memory, so we can pull them into our conscious minds as needed. The oscillations aren’t enough to make the neurons spike. But the brain waves bind together all the neurons in a circuit with every crest, pushing the neurons so close to their firing point that they’re primed to respond to just the slightest extra stimulus. This might help answer a question that has long intrigued scientists: How can the human brain store a virtually unlimited number of long-term memories, yet remain severely limited in the information we can hold in our conscious minds at once? It’s a limit most notably characterized by Princeton cognitive psychologist George Miller (no relation) in a 1956 paper, “The Magical Number Seven, Plus or Minus Two.” George Miller, who helped coin the term working memory, argued that seven, plus or minus two, is the maximum number of objects most of us can hold in our short-term memory at once. Researchers have since demonstrated the number can vary far more widely and may even be smaller than seven. But no one doubts there are limits. If working memory is encoded in oscillations, Earl Miller says it would explain these limits, because a
says something, a lot more people notice it.” Now, Miller is focusing on new technologies that might actually enhance working memory capacity. “If we find a way to stretch the cycle, increase amplitude, make it taller or maybe slow the frequency a little bit, maybe we could increase the capacity of working memory,” he says. So he’s planning on experimenting with a technique that uses electrodes placed on top of the scalp to deliver faint pulses of electricity and record the impact. If these pulses are timed correctly, they could change the shape of the brain waves. It would be a significant technological feat, but Miller thinks it’ll work. If he’s correct, it could have a profound impact on human performance, literally expanding our brainpower. D
BRAIN CELLS, or neurons, connect via complex networks in this scanning electron micrograph.
Adam Piore is the author of The Body Builders: Inside the Science of the Engineered Human, which will be published by Ecco Books in February 2017.
October 2016 DISCOVER
41
A 9-mile-wide asteroid smashed into a shallow sea off Mexico’s Yucatan Peninsula 66 million years ago. Some 75 percent of life on Earth died in the aftermath.
42
DISCOVERMAGAZINE.COM
DRILLING TO
DOOMSDAY An expedition in the Gulf of Mexico gets to the core of the most important event in the past 100 million years. BY ERIC BETZ ILLUSTRATION BY MARK GARLICK
October 2016 DISCOVER
43
FOR BILLIONS OF YEARS, IT WAITED.
A city-sized chunk of primordial space rock circled the solar system somewhere between the orbits of Mars and Jupiter. Earth took shape. Life evolved. And all the while, the space rock just drifted, tumbling end over end like a poorly thrown football. Then, some unknown celestial mechanics shoved this 9-mile-wide projectile out of its orbit. Destination: Earth. The asteroid belt escapee arrived 66 million years ago. In those last dinosaur days, any skygazing T. rex might have tilted its head in curiosity as a strange, new star grew dozens of times brighter than the sun. Burning through the atmosphere at 45,000 mph, the asteroid’s leading edge hit the Gulf of Mexico while its other end was still higher than a cruising 747. It excavated a hole nearly 20 miles deep, ripping fault lines down to Earth’s mantle. For two minutes, land behaved like liquid. The open hole left behind by the asteroid quickly filled back in as material rebounded from the depths, building a great ring of peaks around the crater’s center. Twelfthmagnitude earthquakes rocked the region. Cliffs crumbled. A blast of air surged at speeds exceeding 600 mph, bringing hurricane-force winds to what is now North America. Vegetation vaporized. Within the hour, waves hundreds of feet high pounded Texas and Florida. A debris plume erupted above Earth’s atmosphere and rained back down around the globe, creating regional infernos. These were just the opening salvos of hell on Earth. By chance, the asteroid struck a shallow sea over a sulfurrich shelf. Once vaporized, the chemicals formed a climatealtering blanket that enveloped the planet and fell as acid rain. Photosynthesis nearly stopped. As forests died, wildfires turned the world’s plants into a layer of soot now found all around the planet. Most of the remaining creatures — from the tiniest plankton to the largest dinosaurs — froze or starved. On land, nothing larger than 55 pounds survived.
“Most damaging were the sulfur and the dust. Those two things made the Earth very dark and cold for an extended period of time,” says Joanna Morgan of Imperial College London, who’s spent her career studying the calamity. Some 75 percent of life vanished, ending the 180 million-year reign of the dinosaurs. But life couldn’t be snuffed out so easily. The survivors emerged from the ash to repopulate the planet. A different kind of creature soon flourished in the dinosaurs’ absence — mammals. Now scientists have returned to the scene of the crime, seeking answers to fundamental questions about what happened that day. How exactly did that limestone shelf behave like a liquid? Where did the peak ring rocks come from? And what kinds of life were the first to return to ground zero? Researchers are turning back time, layer by layer, drilling down to the time of the Cretaceous — the final dinosaur era — examining rocks and tiny fossils for new details that could solve decades-old controversies. “It’s the most important natural event on Earth in the last 100 million years,” Morgan says. “It changed the course of evolution.” And if the researchers can find those first species to recolonize the crater, the discovery could teach us not only more about the dinosaurs’ demise, but also how life survived similar events billions of years earlier. Chicxulub crater Drilling expedition
ex
ico
Yucatán Peninsula
The asteroid left a roughly 110-mile-wide crater — now buried beneath sediment — centered near Chicxulub, a tiny Mexican town. Scientists recently drilled into the offshore part of the crater for the first time.
44
DISCOVERMAGAZINE.COM
FROM LEFT: ARIDOCEAN/SHUTTERSTOCK; NASA/JPL
M
Gu lf
of
Chicxulub
FROM TOP: ERIC BETZ (2); MONICA KORTHSHA/UNIVERSITY OF TEXAS JACKSON SCHOOL OF GEOSCIENCES
SPOTTING GROUND ZERO Under the fierce May sun, Morgan steps into an open-air basket on a supply vessel floating 19 miles off the Yucatán Peninsula. A crane operator pulls her high above the rough ocean waves, giving her the asteroid’s final view of the Gulf of Mexico. But there’s no evidence of the apocalypse from here; the coastline isn’t even in sight. Her landing target is the Liftboat Myrtle, a drill rig parked over the planet’s best-preserved large impact scar, now dubbed Chicxulub (pronounced CHICKsoo-loob), after a tiny nearby town. The rig’s feet stand on the shallow seafloor, just 65 feet underwater, and its platform rises well above the waves, providing a stable base for the drill crew. Morgan is here to sink a diamond-tipped drill bit through nearly a mile of Earth’s crust and collect samples. Her journey began in 1994. Three years earlier, scientists had linked the Chicxulub crater to Luis and Walter Alvarez’s incredible theory that a 66 million-year-old worldwide layer of iridium — a material common in asteroids, but not on Earth’s surface — proved a space rock’s crash killed the dinosaurs. Clues from around the Caribbean had helped them home in on this missing crater. First, sandy tsunami sediment was found in Texas. Then tiny tektites — glass bits formed during impacts — turned up in Haiti. Eventually, oil-hunting Mexican geologists handed over drill cores from a strange
The Liftboat Myrtle (above) gives drill crews (right) a stable platform to collect cores from the impact layer. An international team of experts, led by Joanna Morgan of Imperial College London (below, left) and Sean Gulick of the University of Texas, examined those cores in onboard labs.
October 2016 DISCOVER
45
500 ft
1,000 ft
1,500 ft
2,000 ft
2,500 ft
The drill team collected no core for the first roughly 1,500 feet. After that, they carefully extracted 10-foot segments.
Earth was ice-free in the PaleoceneEocene Thermal Maximum — a rapid warming period 55 million years ago. That could mean distinct layers from algae blooms and die-offs.
How soon did life return to ground zero? Scientists hope to find the first colonizers just above the impact layer.
The impact boundary layer should span hundreds of feet and pack a mix of peak ring materials, tsunami debris and melted rocks that fell from the sky.
3,000 ft
3,500 ft
4,000 ft
Scientists expect they’ll pull cores from the peak ring for perhaps thousands of feet below the impact layer. What’s the rock made of and where did it originate? Those are two of the questions they’re drilling to answer.
4,500 ft
5,000 ft *Drilling platform not to scale Scientists and oil prospectors have drilled the crater in the past, but the International Ocean Discovery Program Expedition 364 was the first to explore Chicxulub’s central peak ring. The team hopes to find new clues about how these large craters form and what made the impact so deadly.
46
DISCOVERMAGAZINE.COM
Haiti
Mexico VOODOO PHYSICS By the time Morgan became Shocked quartz is an involved, most experts agreed that impact crater’s smoking gun. These crystals form an asteroid killed the dinosaurs only when rocks in Earth’s and that it landed in Mexico. But crust see extreme pressure. debate still raged over the size of the Chicxulub crater. Some estimated it was nearly twice as big as it really is. Few scientists were studying impacts at the time, and knowing how much energy the asteroid carried depended on knowing the crater’s diameter. Morgan watched as two geologists — Alan Hildebrand of the University of Calgary and Buck Sharpton of the Lunar and Planetary Institute in Houston — sparred over the details. “There were accusations of voodoo physics from one and the other saying your parents were not married,” Morgan jokes. The scientists were trying to tease out gravitational and magnetic anomalies buried beneath more than half a mile of sediment. The young seismologist saw an opportunity. In 1996, Morgan began a three-month seismic study of the site — the first of its kind. Her team towed a large air gun behind a research vessel, blasting the seafloor with seismic waves that would bounce back, revealing a clearer picture of the crater. The next year, she got the two adversaries, Hildebrand and Sharpton, to sign on as co-authors on a paper in Nature that showed the crater stretched 112 to 124 miles. Morgan’s next plan was even more ambitious. She wanted to drill Chicxulub. Morgan asked the International Ocean Discovery Program (IODP), a global collaboration of marine research, for more than $100 million to collect six 2-miledeep cores from around the crater’s center to better understand peak ring formation and the impact’s environmental effects. The IODP sidelined her proposal until she could bring the cost down. The IODP also called for a 3-D site survey before it would consider Morgan’s proposal. She partnered with University of Texas at Austin geophysicist Sean Gulick, who was already studying the Gulf of Mexico. Again, the researchers towed an array of air guns behind their vessel, this time bouncing more than 35,000 sound waves across a network of 115 land and seafloor seismometers. By 2005, their team had collected enough seismic data to reveal Chicxulub’s exact shape.
LUNAR TWIN Beneath the water and sediment, the impact scar looks strikingly similar to Schrödinger crater on the far side of the moon. Both large craters have a circle of hills around their center called a peak ring. Astronomers see such sites all over the solar system, but on Earth, only Chicxulub has an intact peak
LEFT: JAY SMITH. ABOVE: DAVID A. KRING (2)
circular feature they’d found in the Yucatán. Inside was shocked quartz, the smoking gun for impact craters. Scientists had started to assume the impact happened in the open ocean. Chicxulub’s surprisingly sulfur-rich location helped explain the environmental devastation. But that was just the beginning.
GLOBE BACKGROUND BY NASA EARTH OBSERVATORY, BLAST DATA BY IMPERIAL COLLEGE LONDON; DETLEV VAN RAVENSWAAY/SCIENCE SOURCE
Settling the Soot Fossils from New Mexico and Colorado show that the doomsday asteroid of 66 million years ago may have caused entire forests to burn to the ground. And for decades, some scientists thought that happened because the atmosphere superheated the planet, igniting fires everywhere on Earth as fireballs rained down from the skies. But David Kring of the Lunar and Planetary Institute has modeled Chicxulub’s immediate aftermath and shown forest fires were likely more regional — some forests lived, while others died. His team proposes that a thermal pulse is to blame, an explosion of heat reaching more than 36,000 degrees Fahrenheit as it spread from the impact site, igniting nearby areas. If that’s correct, forest fires likely spread across southern North America, but stopped before destroying the continent’s northern reaches. The extended fallout also would have started fires on the opposite side of the planet. “There would have been a huge number of ecosystems on Earth at the time, and those ecosystems would have reacted differently,” says Kring. In research published last year, Joanna Morgan of Imperial College London and her colleagues put that idea to the test by setting pine needles on fire in the lab. The team showed that the thermal pulse from the impact couldn’t ignite the kind of global canopy-replacing wildfires commonly associated with the asteroid. Instead, dry forest litter likely sparked wildfires like the ones forests had evolved with. In Morgan’s version of events, reduced sunlight and re-entering debris may have dried out many of Earth’s plants. Those dead trees and plants later burned as a result. Either way, we’re sure Earth burned. “What we know is there’s lots and lots of soot, so there must have been lots of fires all across the place,” Morgan says. How did these forests bounce back? A 2014 University of Arizona study of fossilized leaves in North Dakota showed a surprising shift in plant populations. Deciduous plants — those that lose their leaves — fared better than slowgrowing evergreens, thanks to their live-fast-die-young strategy. This implies that evergreens were more common before the impact, but fast-growing flowering plants thrived immediately afterward. Fossil records also commonly show a fern spore spike following the impact, indicating that some spores and seeds survived the fires. This helps explain why some avian dinosaurs lived and others died. A paper published in the journal Current Biology earlier this year looked at birdlike creatures living at the end of the Cretaceous and notes that the survivors — those species that went on to become modern birds — had beaks without teeth, ideal for seeds. Carnivorous species died as their food sources did, but those dinosaurs with toothless beaks could feast on fallen seeds long after plants died. E.B.
Air blast A 600 mph air blast (above) immediately followed the impact, shredding nearby animals and vegetation. Hurricane-force winds leveled forests far beyond that. Impact debris (below) soon fell across North America.
Impact ejecta
The impact aftermath killed most life on Earth, but the crater itself — shown with a central peak ring above — remained hot long after the blast, perhaps creating a hydrothermal system similar to deep-sea vents. By drilling the crater offshore, scientists hope to find Chicxulub’s first colonizers.
October 2016 DISCOVER
47
Schrödinger crater
Peak ring
Chicxulub and its buried peak ring resemble the moon’s Schrödinger crater. Peak rings are seen in large craters throughout the solar system. They form when impacts plunge deep below a world’s surface, excavating rock that bounces back up in the center before collapsing. Scientists are still trying to pin down the specifics, like how deep the uplifted rock forms.
How Peak Rings Form Ejecta Tsunami Upper crust Lower crust
Chicxulub crater
ring. And despite the rings’ abundance, scientists still don’t understand exactly how this inner circle forms or how land could weaken enough to behave like a liquid in the immediate Peak ring aftermath, as models predict. “In addition to all the life stuff — all the extinctions, life coming back, all of that — there’s this fundamental quesOuter crater edge tion: How are impacts made?” Gulick says. “And if you want to test the models, this is the place to go because we can get to it without flying to the moon.” After the 2005 seismic survey, the scientific community gathered in support of a new drilling effort, but at $20 million, the price remained too high. It took the recent decline of world oil markets to drop the price tag to around $10 million before a scaled-down version of the project was feasible. “We’re in a lucky window right now,” Morgan says. “The fact that the oil price is low and the oil rigs aren’t busy is very helpful for us.” The IODP eventually agreed to finance the project, and after two decades of work, with help from partner groups, Morgan finally set foot on the Liftboat Myrtle.
Impact
Uplift Peak ring
Collapse
Were Dinosaurs Already Doomed? Most researchers agree that an asteroid struck Earth 66 million years ago and wiped out most life. But were dinosaurs dying off before the impact? In 2016, a long-simmering debate erupted into a roiling boil. An April study in the Proceedings of the National Academy of Sciences examined hundreds of species on the dinosaur evolutionary tree. By looking at the statistics of extinction and speciation events, which happen when new dinosaurs evolve, researchers found signs of decline for many species. Sauropods, a group of large
48
DISCOVERMAGAZINE.COM
plant-eaters like Brontosaurus, may have started dying off 50 million years before the Chicxulub asteroid impact, they found. And by 40 million years before the impact, more species were dying off than new species were evolving. What was killing them? This statistical approach can’t isolate a cause, but the team points out plenty of possibilities: continental drift, intense volcanism, climate change and sea level rise. Another study, this one published in Nature Communications, added fuel to the fire in July. The authors studied
well-preserved Cretaceous ecosystems in Antarctica and found two temperature spikes, including a larger one before the impact. The scientists pin the initial warming on staggering volcanic eruptions that created India’s Deccan Traps around the same time period. However, critics say the fossil record isn’t complete enough for such a sweeping analysis. They point out that other groups, such as marine life and birdlike dinosaurs, show no signs of a struggle. “Don’t let anyone tell you [the extinction] was gradual,” says Timothy Bralower, a micropaleontologist at Pennsylvania State University. E.B.
CLOCKWISE FROM TOP LEFT: NASA’S SCIENTIFIC VISUALIZATION STUDIO; NASA; JAY SMITH
CHECKING THE CORES Morgan and Gulick are no strangers to fieldwork. When she’s not studying Chicxulub, Morgan probes the heart of Greece’s Santorini volcano. And Gulick’s seismic studies have taken him from pole to pole, mapping faults and glaciers, and bringing up cores to reveal Earth’s ancient climate. Standing together on Myrtle’s deck, the two co-chief scientists are ready for more. Both sport dirty red jumpsuits and messy shoulder-length blond locks tucked beneath white hard hats. They’re adorned with the badge of International Ocean Discovery Program Expedition 364: an offshore drill rig under a fireball. As the drill drones on in the background, they share a laugh over rock cores that haven’t seen sunlight since the asteroid impact.
Piles of piping (above) were needed to extend the drill’s reach nearly a mile beneath the surface. This crater layer (below) shows where black impact glass mixed with white limestone fragments during the fallout and tsunami.
Under Morgan and Gulick’s leadership, Liftboat Myrtle finally sinks its drill bit into the seafloor in April. By month’s end, the crew of international experts and drill operators are reeling in 10-foot sections of core, working shifts around the clock in temperatures well above 100 degrees Fahrenheit. As each cylinder of rock comes up from the deep, onboard specialists rush to record its density, resistivity, temperature and any other data that might change before the cores are examined at a main lab in Bremen, Germany. Most layers within the cores are wafer thin, but a few stretch several inches in varying shades of gray. Gulick identifies these as ash from Mexican volcanoes that erupted some 50 million years ago. But such local cataclysms can’t compare with the layer that ended the Cretaceous. Scientists predict the boundary layer — a mix of original peak ring materials, tsunami deposits and melted rocks that fell from the sky — should span hundreds of feet. They finish drilling in late May, bottoming out at a depth of nearly a mile.
DOOMSDAY’S SURVIVORS In one of several air-conditioned shipping containers converted into makeshift-laboratories on the Liftboat Myrtle, Pennsylvania State University micropaleontologist Timothy Bralower lightly breaks up a bit of core rock using a mortar and pestle. Then he dumps the fine fragments onto a glass slide. Countless tiny plankton fossils stare back at him through the microscope. They look like fuzzy grains of quinoa scattered across a black dinner plate. By picking out individual species and comparing them with fossil records, he can tell the team roughly how far back in time they’ve drilled.
It’s a quick and dirty dating technique that reveals when they’re near the most precious core sections — those right before the impact boundary. To prevent contamination, those layers will be sealed and sent intact to Germany, where the 33-person science team will gather in September for a marathon onshore research session, analyzing the samples in 12-hour shifts. The team hopes these precious rocks preserve a record of the first life to return to ground zero. Models show that seawater quickly returned to the crater, and it may have remained bubbling hot for as long as 2 million years after the impact. Ironically, that means the asteroid that helped destroy life on Earth’s surface could have created a habitat below the waves for certain extreme kinds of life, which today gather around deep-sea vents elsewhere. These organisms feed on chemicals with no need for sunlight, making them a great contender for Chicxulub’s new first residents. If so, these species could teach us how life on early Earth — and even Mars — survived more than 4 billion years ago, when asteroids constantly bombarded the planet. “Only the kinds of things living in stressful environments would have survived,” Bralower says. The asteroid impact 66 million years ago — like many before it — fundamentally changed life on Earth. Now, a drill’s impact could alter our very understanding of life. D Eric Betz is an associate editor at Discover. Follow him on Twitter @ericbetz
£
CLOCKWISE FROM TOP LEFT: ERIC BETZ (2); SEAN GULICK/INSTITUTE FOR GEOPHYSICS/UNIVERSITY OF TEXAS
Scientists process cores in plastic liners before they’re shipped to the International Ocean Discovery Program’s core repository in Bremen, Germany, for detailed analysis this fall.
To see more images from Liftboat Myrtle, visit our online gallery at DiscoverMagazine.com/Chicxulub
October 2016 DISCOVER
49
3
¾
%
6
1
8 1
9 +√
WEAPONS OF DESTRUCTION
Credit scores are one of the formulas that determine our world. They often work against us, from job prospects to how long we’re on hold.
3
≠
2
≥
5
BY CATHY O’NEIL
1
4
9
hen I was little, I used to gaze at the traffic out the car window and study license plate numbers. I would reduce each one to its basic elements — the prime numbers that made it up. 45 = 3 x 3 x 5. That’s called factoring, and it was my favorite investigative pastime. My love for math eventually became a passion. I went to math camp when I was 14 and came home clutching a Rubik’s Cube to my chest. Math provided a neat refuge from the messiness of the real world. It marched forward, its field of knowledge expanding relentlessly, proof by proof. And I could add to it. I majored in math in college and went on to get my Ph.D. Eventually, I became a tenure-track professor at Barnard College, which had a combined math department with Columbia College. And then I made a big change. I quit my job and went to work as a quantitative analyst for D. E. Shaw, a leading hedge fund. In leaving academia for finance, I carried mathematics from abstract theory into practice. The operations we performed on numbers translated into trillions of dollars sloshing from one account to another. At first I was excited and amazed by working in this new laboratory, the global economy. But in the autumn of 2008, after I’d
LIGHTKITE/SHUTTERSTOCK
been there for a bit more than a year, it came crashing down.
The crash made it all too clear that mathematics, once my refuge, was not only deeply entangled in the world’s problems, but also fueling many of them. The housing crisis, the collapse of major financial institutions, the rise of unemployment — all aided and abetted by mathematicians wielding magic formulas. What’s more, thanks to the extraordinary powers I loved so much, math combined with technology to multiply the chaos and misfortune, adding efficiency and scale to systems that I now recognized as flawed. If we had been clear-headed, we all would have taken a step back to figure out how math had been misused and how we could prevent a similar catastrophe in the future. But instead, in the wake of the crisis, new mathematical techniques were hotter than ever, and expanding into still more domains. They churned 24/7 through petabytes of information, much of it scraped from social media or e-commerce websites. And increasingly, they focused not on the movements of global financial markets but on human beings — on us. Mathematicians and statisticians were studying our desires, movements and spending power. They were predicting our trustworthiness and calculating our potential as students, workers, lovers, criminals. This was the Big Data economy, and it promised
spectacular gains. A computer program could speed through thousands of résumés or loan applications in seconds and sort them into neat lists, with the most promising candidates on top. This not only saved time but also was marketed as fair and objective. After all, it didn’t involve prejudiced humans digging through reams of paper, just machines processing cold numbers. By 2010 or so, mathematics was asserting itself as never before in human affairs. Yet I saw trouble. The math-powered applications driving the data economy were based on choices made by fallible human beings. Some of these choices were no doubt made with the best intentions. Nevertheless, many of these models and algorithms encoded human prejudice, misunderstanding and bias into the software systems that increasingly managed our lives. Like gods, these mathematical models were opaque, their workings invisible to all but the highest priests in their domain: mathematicians and computer scientists. Their verdicts, even when wrong or harmful, were beyond dispute or appeal. And they tended to punish the poor and the oppressed in our society, while making the rich richer. I came up with a name for these harmful models: Weapons of Math Destruction, or WMDs for short.
October 2016 DISCOVER
51
And the human victims of WMDs, we’ll see time and again, are held to a far higher standard of evidence than the algorithms themselves. Welcome to the dark side of Big Data.
A FAIR MODEL Local bankers used to stand tall in a town. They controlled the money. If you wanted a new car or a mortgage, you’d put on your Sunday best and pay a visit. And as a member of your community, this banker would probably know certain details about your life. He’d know about your churchgoing habits, or lack of them. He’d know all the stories about your older brother’s run-ins with the law. He’d know what your boss (who was also his golfing buddy) said about you as a worker. Naturally, he’d know your race and ethnicity and he’d also glance at the numbers on your application. The first four factors often worked their way, consciously or not, into the banker’s judgment. And there’s a good chance he was more likely to trust people from his own circles. This was only human. But for millions of Americans, it meant the predigital status quo was challenging, to say the least. Outsiders, including minorities and women, were routinely locked out. They had to create an impressive financial portfolio — and then hunt for open-minded bankers. It wasn’t fair. And then along came an algorithm, and things improved.
In the 50s, a mathematician named Earl Isaac and his engineer friend, Bill Fair, devised a model they called Fair, Isaac, and Corporation (FICO) to evaluate the risk of an individual defaulting on a loan. This FICO score was fed by a formula that looked only at a borrower’s finances — mostly his or her debt load and bill-paying record. The score was colorblind. And it turned out to be great for banks because it predicted risk far more accurately while opening the door to millions of new customers. FICO scores are still around. They’re used by the credit agencies, including Experian, Transunion, and Equifax, which each contribute different sources of information to the FICO model to come up with their own scores. These scores have lots of commendable, non-WMD attributes. First, they have a clear feedback loop. Credit companies can see which borrowers default on their loans, and they can match those numbers against their scores. If borrowers with high scores seem to be defaulting on loans more frequently than the model would predict, FICO and the credit agencies can tweak those models to make them more accurate. This is a sound use of statistics. The credit scores are also relatively transparent. FICO’s website, for example, offers simple instructions on how to improve your score. (Reduce debt, pay bills on time and stop
his technology races through available data on callers and places them in a hierarchy. Those at the top are deemed more profitable prospects and are quickly funneled to a human operator. Those at the bottom wait much longer.
52
DISCOVERMAGAZINE.COM
ordering new credit cards.) Equally important, the credit-scoring industry is regulated. If you have questions about your score, you have the legal right to ask for your credit report, which includes all the information that goes into the score, including your record of mortgage and utility payments, your total debt and the percentage of available credit you’re using. Though the process can be torturously slow, if you find mistakes, you can try to have them fixed. Since Fair and Isaac’s pioneering days, the use of scoring has proliferated wildly. Today, we’re added up in every conceivable way as statisticians and mathematicians patch together a mishmash of data, from our ZIP codes and internet surfing patterns to our recent purchases. Many of their pseudoscientific models attempt to predict our creditworthiness, giving each of us so-called e-scores, which are based on numerous variables such as our occupation, what our houses are valued at and our spending habits. These numbers, which we rarely see, open doors for some of us, while slamming them in the face of others. Unlike the FICO scores they resemble, e-scores are arbitrary, unaccountable, unregulated and often unfair — in short, they’re WMDs. One Virginia company offers a prime example. It provides customertargeting services for companies, including one that helps manage
OPPOSITE: PHYZICK/SHUTTERSTOCK (BACKGROUND) AND STUDIOSTOKS/SHUTTERSTOCK. THIS PAGE: STUDIOSTOKS/SHUTTERSTOCK
call center traffic. In a flash, this technology races through available data on callers and places them in a hierarchy. Those at the top are deemed more profitable prospects and are quickly funneled to a human operator. Those at the bottom either wait much longer or are dispatched into an outsourced overflow center, where they’re handled largely by machines. Credit card companies carry out similar rapid-fire calculations as soon as someone shows up on their website. They can often access data on web browsing and purchasing patterns, which provide loads of insights about the potential customer. Chances are, the person clicking for new Jaguars is richer than the one checking out a 2003 Taurus on Carfax.com. Most scoring systems also read the location of the visitor’s computer. When this is matched with real estate data, they can draw inferences about wealth. A person using a computer on San Francisco’s posh Balboa Terrace is a far better prospect than one across the bay in East Oakland.
Now consider the nasty feedback loop e-scores create. There’s a very high chance the e-scoring system will give the borrower from the rough section of East Oakland a low score. Lots of people default there. So the credit card offer popping up will be targeted to a riskier demographic. That means less available credit and higher interest rates for those who are already struggling. E-scores are only stand-ins for credit scores. But since companies are legally prohibited from using credit scores for marketing purposes, they make do with this sloppy substitute. There’s a certain logic to that prohibition. After all, our credit history includes highly personal data and it makes sense that we should have control over who sees it. But the consequence is that companies end up diving into largely unregulated data pools to create a parallel data marketplace. In the process, they largely avoid government oversight. They then measure success by gains in efficiency, cash flow and profits.
With few exceptions, concepts like justice and transparency don’t fit into their algorithms. Let’s compare that to the 1950s-era banker. Consciously or not, that banker was weighing various data points that had little or nothing to do with his would-be borrower’s ability to shoulder a mortgage. He looked across his desk and saw his customer’s race and drew conclusions from that. The customer’s father’s criminal record may have counted against him or her, while regular church attendance may have helped. All of these data points were proxies. In his search for financial responsibility, the banker could have dispassionately studied the numbers (as some exemplary bankers no doubt did). But instead, he drew correlations to race, religion and family connections. In doing so, he avoided scrutinizing the borrower as an individual and instead lumped him in a group of people — what statisticians today call a bucket. “People like you,” he decided, could or couldn’t be trusted.
October 2016 DISCOVER
53
Fair and Isaac’s great advance was to ditch the proxies in favor of the relevant financial data, like past bill-paying behavior. They focused their analysis on the individual — not on other people with similar attributes. E-scores, by contrast, march us back in time. They analyze the individual through a veritable blizzard of proxies. In a few milliseconds, they carry out thousands of “people like you” calculations. And if enough of these “similar” people turn out to be deadbeats or, worse, criminals, that individual will be treated accordingly.
THE PROBLEM WITH PROXIES From time to time, people ask me how to teach ethics to a class of data scientists. I usually begin with a discussion of how to build an e-score model and ask them whether it makes sense to use “race” as an input in the model. They inevitably respond that such a question would be unfair and probably illegal. The next question is whether to use “ZIP code.” This seems
fair enough, at first. But it doesn’t take long for the students to see they’re codifying past injustices into their model. When they include an attribute such as “ZIP code,” they’re expressing the opinion that the history of human behavior in that patch of real estate should determine, at least in part, what kind of loan a person who lives there should get. In other words, the modelers for e-scores have to make do with trying to answer the question “How have people like you behaved in the past?” when ideally they would ask, “How have you behaved in the past?” I should note that in the statistical universe proxies inhabit, they often work. Birds of a feather do tend to flock together. Rich people buy cruises and BMWs. All too often, poor people need a payday loan. And since these statistical models appear to work most of the time, efficiency rises and profits surge. Investors double down on scientific systems that can place thousands of people into what appear to be the correct buckets. It’s the
triumph of Big Data. But what about the person who is misunderstood and placed in the wrong bucket? That happens. And there’s no feedback to set the system straight. A statistics-crunching engine has no way to learn it dispatched a valuable potential customer to call center hell. Worse, losers in the unregulated e-score universe have little recourse to complain, much less correct the system’s error. In the realm of WMDs, they’re collateral damage. And since the whole murky system grinds away in distant server farms, they rarely find out about it. Most of them probably conclude, with reason, that life is simply unfair.
CREDIT IS A VIRTUE In the world I’ve described so far, e-scores nourished by millions of proxies exist in the shadows, while our credit reports, packed with pertinent and relevant data, operate under rule of law. But sadly, it’s not quite that simple. All too often, credit reports serve as proxies, too.
THIS PAGE AND OPPOSITE: STUDIOSTOKS/SHUTTERSTOCK
f people pay their bills on time, employers ask, doesn’t that signal dependability? Creditworthiness has become an easy stand-in for other virtues. Conversely, bad credit has grown to signal a host of sins that have nothing to do with paying bills.
It shouldn’t be surprising that many institutions in our society, from big companies to the government, are on the hunt for trustworthy and reliable people. So when it comes to hiring, an all-too-common approach is to consider the applicant’s credit score. If people pay their bills on time and avoid debt, employers ask, doesn’t that signal trustworthiness and dependability? It’s not exactly the same, they know. But wouldn’t there be a significant overlap? That’s how credit reports have expanded far beyond their original turf. Creditworthiness has become an all-too-easy stand-in for other virtues. Conversely, bad credit has grown to signal a host of sins and shortcomings that have nothing to do with paying bills. For certain applications, such a proxy might appear harmless. Some online dating services, for example, match people based on credit scores. One of them, CreditScoreDating, proclaims that “good credit scores are sexy.” We can debate the wisdom of linking financial behavior to love. But at least the customers of CreditScoreDating know what they’re getting into and why. It’s up to them. But if you’re looking for a job, there’s an excellent chance that a missed credit card payment or late fees on student loans could be working against you. According to a survey by the Society for Human Resource Management, nearly half of America’s employers screen potential hires by looking at their credit reports. Some of
them check the credit status of current employees as well, especially when they’re up for a promotion. Before companies carry out these checks, they must first ask for permission. But that’s usually little more than a formality; at many companies, those refusing to surrender their credit data won’t even be considered for jobs. And if their credit record is poor, there’s a good chance they’ll be passed over. A 2012 survey on credit card debt in low- and middleincome families made this point all too clear. One in 10 participants reported hearing from employers that blemished credit histories had sunk their chances, and it’s anybody’s guess how many were disqualified by their credit reports but left in the dark. While the law stipulates employers must alert job seekers when credit issues disqualify them, it’s hardly a stretch to believe some of them simply tell candidates they weren’t a good fit or that others were more qualified. The practice of using credit scores in hirings and promotions creates a dangerous poverty cycle. After all, if you can’t get a job because of your credit record, that record will likely get worse, making it even harder to land work. It’s not unlike the problem young people face when they look for their first job — and are disqualified
for lack of experience. Or the plight of the longtime unemployed, who find that few will hire them because they’ve been without a job for too long. It’s a spiraling and defeating feedback loop for the unlucky people caught in it. Employers, naturally, have little sympathy for this argument. Good credit, they argue, is an attribute of a responsible person, the kind they want to hire. But framing debt as a moral issue is a mistake. Plenty of hardworking and trustworthy people lose jobs every day as companies fail, cut costs, or move jobs offshore. These numbers climb during recessions. And many of the newly unemployed find themselves without health insurance. All it takes is an accident or an illness for them to miss a loan payment. Even with the Affordable Care Act, which reduced the ranks of the uninsured, medical expenses remain the single biggest cause of bankruptcies in America. This isn’t to say personnel departments across America are intentionally building a poverty trap. They no doubt believe credit reports hold relevant facts that help them make important decisions. After all, “the more data, the better” is the guiding principle of the Information Age. Yet in the name of fairness, some of this data should remain uncrunched. D
Adapted from WEAPONS OF MATH DESTRUCTION: HOW BIG DATA INCREASES INEQUALITY AND THREATENS DEMOCRACY Copyright © 2016 by Cathy O’Neil. Published by Crown Publishers, an imprint of Penguin Random House LLC.
October 2016 DISCOVER
55
Stay Up-to-Date with Discover Digital Editions!
Be the first to know about breakthroughs in astronomy and space science, medicine and the mind, technology and the environment with Discover for your tablet or mobile device! The digital edition features: • • •
Enhanced text views for easier on-screen reading. Live links to extra online content and advertisers’ websites. Crystal-clear photos and illustrations you can zoom in on and examine in detail.
It’s everything you expect from Discover ... in a paper-free format!
Subscribe today at DiscoverMagazine.com/digital P28618
Powered by ZinioTM, digital editions are available on PC; Macintosh®; AndroidTM; iPad®; iPhone®; and Windows 8. Zinio is a registered trademark of Zinio, LLC. Android is a trademark of Google Inc. Macintosh, iPad, and iPhone are trademarks of Apple Inc., registered in the United States and other countries. Windows is a registered trademark of Microsoft Corporation in the United States and other countries.
SPECIAL
BONUS
SECTION
OUT THERE
A Look at the Universe and All Its Wonders
Powered by
magazine
THE ECLIPSE EXPERIENCE To witness this total eclipse in 2002, viewers had to travel to Australia. It’s an event that hasn’t been seen from the U.S. mainland since 1979, but next Aug. 21, an eclipse will go coast to coast. Its path will cross 10 states, giving millions the chance to witness one of nature’s greatest spectacles without getting a passport stamp — so start preparing now with the 25 solar eclipse viewing tips by Astronomy Senior Editor Michael E. Bakich on page 58. For a different kind of observing, see page 62 to learn how Stephen James O’Meara’s uncanny eyesight detected details in Saturn’s rings that could only be confirmed by spacecraft. And for the future of sky-watching, see Eric Betz’s story on page 66 about the growing network of roof cameras that track fireballs streaking through the sky. ERNIE MASTROIANNI; PHOTO BY DAVID GRAY/REUTERS
October 2016 DISCOVER
57
SPECI A L BONUS SECTION
OUT THERE
Plan Now for the
2017 ECLIPSE Follow these 25 common sense tips, and you’ll be ready to rock on eclipse day. BY MICHAEL E. BAKICH
→
Are you getting excited yet? As you read this, we’re less than a year away from the biggest celestial event of our lives — the total solar eclipse that will cross the continental United States on August 21, 2017. Lots of people already have decided where they want to view the spectacle. (If you haven’t, don’t worry. There’s still time.) Many hopeful eclipse watchers are making it the centerpiece of their 2017 summer vacations. And even if your big travel plans occur before the eclipse, it’s not a bad idea to view this event like you would a vacation. To that end, I’ve gathered 25 common sense tips that will help you get into the proper mindset. Once you’ve done that, you’re ready to set a plan in motion that will let you have the time of your life.
58
DISCOVERMAGAZINE.COM
You may think just under a year is a bit of a long lead-time. But the point to consider is that August 21, 2017, may turn out to be the most popular vacationday request in history. If not now, figure out the earliest date that makes sense for you to request August 21 as a vacation day, and mark it on your calendar.
17 AUGUST 20
6 13 20 27
7 14 21 28
1 8 15 22 29
2 9 16 23 30
3 10 17 24 31
4 11 18 25
5 12 19 26
2
The eclipse occurs on a Monday. Lots of related activities will occur on Saturday and Sunday in locations touched by the Moon’s inner shadow. Find out what they are, where they’re being held, and which you want to attend, and make a mini-vacation out of the eclipse.
3
Watch the weather
Meteorologists study a chaotic system. Nobody now can tell you with certainty the weather a location will experience on eclipse day. So, don’t get too tied up in the predictions of cloud cover you’ll see for that date. Many don’t distinguish between “few” (one-eighth to two-eighths of the sky covered), “scattered” (threeeighths to four-eighths), “broken” (five-eighths to seven-eighths) clouds, and overcast. One online repository of knowledge I can recommend is Canadian meteorologist Jay Anderson’s Eclipser website (www.eclipser.ca).
Pat
ho
If your interests include celestial happenings and public service, consider volunteering with a group putting on an eclipse event. You’ll learn a lot and make some new friends in the process. Don’t worry if you don’t know eclipses inside and out. After a year of helping prepare, you will.
5
6
Stay flexible
Unless you’re certain August 21 will be clear, don’t do anything you can’t undo in a short time. For example, say you’re taking a motor home to a site. You connect it to power, extend the awnings, set up chairs, and more. But if it’s cloudy six hours, three hours, or even one hour before the eclipse starts, you’re going to want to move to a different location. Think of the time you would have saved if you had waited to set up. Also, the earlier you make your decision to move, the better. Just imagine what the traffic might be like on eclipse day.
7
Concentrate on the sky
Totality will be the shortest two and a half minutes of your life. All your attention should be on the Sun. Anything else is a waste. And be considerate of those around you. Please, no music.
tali
ty
Percentage of mean cloud cover for August
Attend an event
You’ll enjoy the eclipse more if you hook up with like-minded people. If you can’t find any special goingson, call your local astronomy club, planetarium, or science center. Any person you talk to is sure to know of eclipse activities. Travel companies, like Discover’s partner TravelQuest, also offer trips that will let you experience the full social impact of the eclipse.
f to
80
70
60
50
40
good-sized hill, you may see the Moon’s shadow approaching along the ground from the northwest to the southeast. This sighting isn’t easy because as the shadow crosses the U.S., it is moving at a minimum of Mach 1.5 (1,151 mph, 1,852 km/h) and a maximum of Mach 3.5 (2,685 mph, 4,321 km/h). Another way to spot our satellite’s shadow is as it covers thin cirrus clouds if any are above your site. I hope you don’t experience clouds, but if you do, you’ll be surprised how fast the shadow moves.
9
30
20
3 This eclipse-track map shows the average afternoon August cloudiness derived from 22 years of satellite observations.
Notice it getting cooler?
Point a camera that records video at a digital thermometer and a watch, both of which you previously attached to a white piece of cardboard. Start recording video 15 or so minutes before totality and keep shooting until 15 minutes afterward. The results may surprise you.
a filter 10Get in advance
Heading off with a group organized by a tour provider will allow you to experience the social impact of the eclipse.
Cardboard eclipse “glasses” with lenses of optical Mylar cost less than $2. Such a device — it’s not
5
→
OPPOSITE: KEN WILSON. THIS PAGE: JAY ANDERSON (MAP); CIMSS/NOAA/UW-MADISON (DATA); MICHAEL E. BAKICH (PARTY)
Make it a long weekend
4Get involved
→
1
Take eclipse day off
8
Watch for the approach of the Moon’s shadow
If your viewing location is at a high elevation, or even at the top of a
July/August October 2016 DISCOVER
59
SPECI A L BONUS SECTION
OUT THERE
→
→ 10 Although these solar viewing glasses from Rainbow Symphony resemble sunglasses, they are not sunglasses. The only object you’ll see through them is the Sun.
a toy — will let you safely look directly at the Sun anytime. Another safe solar filter is #14 welder’s glass, which also will cost you about $2. Wanna look cool at the eclipse? Buy goggles that will hold the welder’s glass. I’ve even seen people wearing whole helmets. Either those or goggles serve one purpose — you won’t need to hold the filter, so you can’t drop it. The downside is comfort. August 21 will be warm across the U.S. and, in many locations, humid.
the 11View 360° sunset
A couple of times during totality, take a few seconds to tear your eyes away from the sky and scan the horizon. You’ll see sunset colors all around you because, in effect, those locations are where sunset (or sunrise) is happening.
12
Pee before totality
At organized events, sweet relief will be a short walk away. Finish your business well before totality.
Yes, I could have phrased this more politely, but you needed to read it. This tip, above any other on this list, could be the most important one for you. Don’t wait until 10 minutes before totality to start searching for a bathroom. Too much is happening then. Make a pre-emptive strike 45 minutes prior.
12
→
13
No filter? You can still watch the eclipse Except during totality, never look at the Sun. But what if you’ve forgotten a filter? You can still watch by making a pinhole camera. It can be as simple as two pieces of paper with a tiny hole in one of them. (Try to make the hole as round as you can, perhaps with a pin or a sharp pencil.) Line up the two pieces with the Sun so the one with the hole is closest to it. The pinhole will produce a tiny image, which you’ll want to have land on the other piece of paper. Moving the two pieces farther apart will enlarge the Sun’s image but will also lessen its brightness. Work out the best compromise.
14
Bring a chair
In all likelihood, you’ll be at your viewing site several hours before the eclipse starts. You don’t really want to stand that whole time, do you? Are friends coming? Provide a chair for everyone.
15
Don’t forget sunscreen
Most people who go outside during the summer know this. Remember, you’ll be standing around or sitting outside for hours. You may
want to bring an umbrella for some welcome shade. And if you see someone who has forgotten sunscreen, please be a peach and share. This is true solar safety.
lots 16Take of pictures
Be sure to capture images of your viewing site and the people with whom you shared this great event. If you have a camera that records video, I suggest you mount it on a tripod, position it about 25 feet (8 meters) away, aim it toward your group, and record from 15 minutes before totality to 15 minutes after. You’ll document all your reactions and the darkening and brightening of your site. (Note: If your camera automatically compensates for darkness, disable that feature.)
totality 17Regard as sacred
In the August 1980 issue of Astronomy, author Norm Sperling contributed a “Forum” titled “Sperling’s 8-second Law” in which he tries to convey how quickly totality seems to pass. I’ll just quote the beginning here. “Everyone who sees a total solar eclipse remembers it forever. It overwhelms the senses, and the soul as well — the curdling doom of the onrushing umbra, the otherworldly pink prominences, and the ethereal pearly corona. And incredibly soon, totality terminates. “Then it hits you: ‘It was supposed to last a few minutes — but that couldn’t have been true. It only seemed to last eight seconds!’ ”
snacks 18Bring and drinks
You’re probably going to get hungry — and in the summer in the U.S., you definitely will get thirsty — waiting for the eclipse to start. Unless you set up next
60
DISCOVERMAGAZINE.COM
GLASSES: RAINBOW SYMPHONY. KIDS: MICHAEL E. BAKICH. BATHROOMS: DAVID SHANKBONE/WIKIMEDIA COMMONS
16
Pictures of friends really help you relive eclipses even years after the events. This shot of Shadow Winter demonstrates the proper use of eclipse glasses.
19
Remember that no one will have seen totality If you’re planning an event or a family gathering related to the eclipse, consider this: Statistically, 100 percent of the people you encounter — to a high degree of accuracy — will never have experienced darkness at noon. You will be the expert.
20
Invite someone with a solar telescope If you’re hosting a private shindig, make sure someone brings a telescope with a solar filter. While it’s true that you don’t need a scope to view the eclipse, having one there will generate buzz, and it will help Sun-watchers get the most from their experience. And you (or the scope’s owner) can point out sunspots, irregularities along the Moon’s edge, and more. You can even take a look at Venus.
21
Experience totality all by yourself
MICHAEL E. BAKICH (2)
22
Schedule an after-eclipse party or meal
Regarding No. 21, once the eclipse winds down, you’ll be on an
your 23Record memories
Sometime shortly after the eclipse, when the event is still fresh in your mind, take some time to write, voice-record, or make a video of your memories, thoughts, and impressions. A decade from now — or, more specifically, just before the next U.S. total solar eclipse in 2024 — such a chronicle will help you relive this fantastic event. Have friends join in, too. Stick a video camera in their faces and capture 30 seconds from each of them. You’ll smile each time you watch it.
24
Don’t be in a rush afterward
Traffic, or the version of it we all will experience on eclipse day — gridlock — will be horrendous after the event at some locations. And the sooner you try to leave, the worse it will be. Relax. Let the part of the eclipse between third and fourth contacts play out. Many people will view this portion as “what we saw before totality, but in reverse.” For this section, however, all the tension will be gone.
25
Don’t photograph it
This tip may sound strange coming from the photo editor of the best-selling astronomy magazine on Earth. But I’ve preached it to thousands of people whom I’ve led to far-flung corners of our planet to stand under the Moon’s shadow. True, few of them have thanked me afterward. But I can tell you of upward of a hundred people who have told me with trembling voices, “I wish I’d followed your advice. I spent so much time trying to center the image and get the right exposures that I hardly looked at the eclipse at all.” How sad is that? And here’s another point: No picture will capture what your eyes will reveal. Trust me, I’ve seen
them all. Only the top 0.1 percent of photographers ever has come close. And you — no offense — with your off-the-shelf SLR or point-and-shoot pocket camera are not one of them. Finally, why would you even consider looking down and fiddling with a camera when you could be looking up at all that heavenly glory? This eclipse will — at maximum — last 160 seconds. That’s it, friends. If your camera isn’t doing what you think it should, you’re going to lose valuable time adjusting it. There will be plenty of pics from imagers who have viewed a dozen of these events. So just watch. Watch your first eclipse with your mouth agape, where your only distraction is occasionally wiping tears of joy from your eyes. I promise that you will not be disappointed.
Now, relax Once you come up with a course of action that lets you stay flexible with some of the details, you’ll feel a lot better as August 21, 2017, approaches. And the family and friends that you include surely will say, like Bill Murray’s character Dr. Peter Venkman in the movie Ghostbusters, “I love this plan. I’m excited to be a part of it!” D
20 Amateur astronomer John Volk shared views of the Sun through his telescope during the November 13, 2012, total solar eclipse in Australia. Note the approved solar filter covering the front of his scope. Astronomy Contributing Editor Mike Reynolds has seen 16 total solar eclipses. If you haven’t seen any, just watch the spectacle and photograph your next one.
25
→
The 2017 eclipse, plus the events leading up to it, will combine to be a fabulous social affair. Totality itself, however, is a time that you should mentally shed your surroundings and focus solely on the sublime celestial dance above you. You’ll have time for conversations later.
emotional high for hours, and so will everyone else. There’s no better time to get together with family and friends and just chat. Fun!
→
to a convenience store, bring some light snacks and plenty to drink. Remember, even if you’re attending a sponsored event, there’s no guarantee water vendors won’t run out. Some places will have many times the number of people they expect. Don’t trust someone else with your comfort.
Michael E. Bakich is a senior editor of Astronomy. He will be conducting a massive public viewing party for the eclipse at Rosecrans Memorial Airport in St. Joseph, Missouri. See www.fpsci.com for details.
October 2016 DISCOVER
61
SPECI A L BONUS SECTION
OUT THERE
Confessions of an Eagle-Eyed Observer No one believed an amateur astronomer saw such fine details in Saturn’s rings. Then Voyager saw them, too. BY STEPHEN JAMES O’MEARA
→
One night 40 years ago, in the spring of 1976, planetary astronomer Fred Franklin walked up the four flights of stairs from his office to the Harvard College Observatory in Cambridge, Massachusetts, and entered the dome of the 9-inch Alvan Clark refractor — where he changed my life with a question. “Steve, do you think you can detect a one-tenth-magnitude brightness difference in Saturn’s A ring?” he asked. I looked at him, puzzled, and asked,
62
DISCOVERMAGAZINE.COM
“Do you mean if I can see Encke’s Division with the 9-inch?” The division is an anemic split near the outer edge of ring A, which requires excellent atmospheric stability to spy. “No.” Fred shook his head, explaining that the brightness of Saturn’s A ring is not constant but varies at four points, with two quadrants symmetrically fainter by 0.1 magnitude than the other two. Fred wondered if I could visually determine which quadrants were brighter and which were fainter;
he wanted to compare the visual results with photometric observations he was taking with a 16-inch reflector at Harvard’s remote Oak Ridge Observatory. Considering my routine brightness estimates of variable stars to within 0.1 magnitude, I told him it might be possible and was eager to try.
OBSERVING LESSONS I started by observing Saturn through an eyepiece that yielded 125x. I
NASA/JPL/SPACE SCIENCE INSTITUTE
The ringed planet saw seasons change for billions of years before NASA’s Cassini spacecraft caught this first shot of saturnian equinox.
TOP: NASA/JPL/SPACE SCIENCE INSTITUTE. BOTTOM IMAGES: CASSINI IMAGING TEAM, ISS, JPL, ESA, NASA
Saturn’s phantom spokes appear as bright radial lines reaching out across the planet’s rings.
thought I could maximize my chances of success by condensing the light of the A ring, which would make any brightness differences more noticeable. But I abandoned the search because light from the B ring overpowered the view. I also realized that trying to search for “possible” 0.1-magnitude differences across a single expanse of light was different from comparing a variable star of unknown brightness to different point sources of known brightness.
I had to rethink my strategy. Because Saturn was high in the sky after sunset, I decided to start observing as soon as it became visible in the twilight. This double-star observing technique would reduce the contrast between the A and B rings, allowing me a better view. I also selected an 8.4mm Fecker eyepiece (a simple design combining two lenses) that provided a narrow field of view (10') and a magnification of 327x through the 9-inch refractor. In addition, I placed the much brighter ball
of the planet outside the field of view so I could focus on only one side of Saturn’s rings at a time. I had to train myself to stare directly at ring A, using my detail-sensitive cone cells rather than my eye’s night-sensitive rod cells, which have poor spatial resolution. Eventually my observing eye was comfortable with the adjustments, and the brightness variations within Saturn’s A ring revealed themselves convincingly. But Fred didn’t just want verbal confirmation. He asked me to
July/August October 2016 DISCOVER
63
SPECI A L BONUS SECTION
OUT THERE
The author made these sketches of Saturn’s ring spokes in the 1970s, years before Voyager “discovered” them.
NEW AND MYSTERIOUS FEATURES When the project ended, I found myself staring at Saturn through the 9-inch scope, pondering, “If Fred is looking for slight brightness variations in the A ring, perhaps the B ring has them as well.” Curious, I set out to look for 0.1-magnitude brightness differences along ring B. Although I used the same observing technique, I failed to detect a symmetrical variation along the ring. (Later I would learn that, indeed, no such effect exists for ring B). But I did spy something new: Saturn’s B ring had a different type of azimuthal structure. Radial markings
64
DISCOVERMAGAZINE.COM
The author looks into the 15-inch Great Refractor at Harvard College Observatory.
extend outward from the ring’s dusky inner section partly across the ring, like fingers splayed from an outstretched hand. The radial features were only 0.1 magnitude darker than their surroundings, and I mostly observed them along the eastern side of the B ring. At times the radial markings appeared jagged or toothy. At other times they were more fingerlike, while still others looked sharp and needlelike. They also were not consistent in location or number, appearing at different points on different days and in different numbers. Radial features occasionally appeared on the western side of the B ring, but these were not as prominent, far fewer, and less frequent. When I showed Fred the initial results of my new study, he appeared more puzzled than surprised. He took out a 1962 copy of A.F.O’D. Alexander’s The Planet Saturn and showed me some drawings by Eugene Antoniadi and others that displayed dark radial features in ring A.
And while he called these drawings and my observations “fascinating,” he added that unfortunately they had to be some sort of illusion. His reasoning was sound: Saturn’s rings are a Keplerian disk, with its inner particles revolving faster than the outer ones. Therefore, shear forces would rip apart anything that stretched out radially across the rings. Try as I might, I could not convince Fred or others of the radial features’ reality. Instead, I was met with a seemingly unified resistance. As James Bryant of McDonald Observatory would later write in the 2007 Journal of Astronomical History and Heritage, “[While his] audience knew him to be honest, competent, free of agenda … his evidence was very difficult to accept because it ran contrary to physics. … Inaction that followed O’Meara’s report of spokes in 1976 may have been caused by others’ distrust of the visual method he used.”
COURTESY STEPHEN JAMES O’MEARA: CLOCKDRIVE PRODUCTIONS
make a sketch of the rings and place a “+” or “–” sign in the appropriate quadrants where I suspected variation. When I shared my initial results with Fred, he said he found them “interesting” but remained noncommittal, simply suggesting I continue trying. For about a month I slid drawings underneath his office door without hearing any further comment — until, one night, Fred shared with me that my visual observations were aligned with the photometric ones, and that congratulations were in order.
HARVARD-SMITHSONIAN CENTER FOR ASTROPHYSICS
GOING IT ALONE While I understood the reasoning behind others’ disbelief, further observations of the features convinced me they were real. I could not dismiss them as an atmospheric phenomenon or telescopic illusion. Over the next four years, I conducted a systematic observing campaign of the B ring. I submitted the results to journals for publication without success. For instance, in 43 days (January 24 to March 8, 1977), I observed 29 radial features (or radial complexes) when Saturn’s rings were tilted around 17° to our line of sight. The more I observed them, the more dissimilar they became to ring A’s azimuthal variations. On some evenings, I would monitor the radial shadings for hours, watching the motion of individual streaks, which not only rotated in the same direction as the planet’s cloud tops but also at a similar rate. I also followed the radial features through changing ring-angle phases (from about 17° in 1976 to nearly edge-on in 1980). During that time, I created graphs that showed how the prominence and number of these radial features diminished dramatically as the rings’ angle decreased. My systematic observations ended in 1980 when Saturn and its near edge-on rings went into conjunction with the Sun — also just before Voyager 2 arrived at Saturn and obtained credit for the discovery of Saturn’s radial “spokes” … but not before I had one last chance to be heard. Prior to Voyager 2’s arrival at Saturn, I showed a sample of my Saturn drawings to Sky & Telescope’s J. Kelly Beatty, who was leaving for the Jet Propulsion Laboratory to cover the event. Kelly first showed me the latest images from the spacecraft, then I handed him some of my drawings, saying, “Please call me when Voyager images these features in ring B,” and pointed out the radial shadings. Kelly chuckled and said, “Right.” About a week later, Kelly saw the Voyager 2 images of the
For years, the author used Harvard College Observatory’s 9-inch Alvan Clark refractor to observe Saturn.
spokes appear on a large screen at the JPL pressroom. He said he fell back in his chair, exclaiming that I had seen the spokes four years ago. As Mark Washburn records in Distant Encounters, “The news traveled quickly, and an hour later [Voyager imaging team leader] Brad Smith appeared in the pressroom, asking Beatty, ‘What’s this I hear about someone seeing spokes?’ ” Like others, Smith was unconvinced. Regardless, Kelly did call, and I was astounded by the news.
RIDDLE ME THIS Now that spacecraft have imaged the spokes, scientists are trying to solve the riddle of their existence. One theory is that the ring’s icy dust particles get an electrostatic charge when they move out of Saturn’s shadow and into sunlight. (It’s the same type of electrostatic discharge that causes static cling when you pull clothes from a dryer.) The charge levitates the particles above the ring plane and into Saturn’s magnetic field, which co-rotates with the planet. One mystery, however, is that the spokes can disappear for long periods of time. For instance, they remained elusive from 1998 to 2005 — even to the Cassini spacecraft when it arrived in 2004. Cassini did begin to detect them in 2005, albeit weakly. That prompted scientists to speculate that spokes may appear mainly during certain seasons of the long saturnian year, perhaps in response to the changing
angle at which sunlight hits the rings. If so, spokes may have seasons, and may not form at times when the Sun is between 17° and 24° above the ring plane. (Interestingly, my pre-Voyager observations took place when the Sun was between 16.5° and 3° above the ring plane, during a theoretical time of maximum spoke production.) Other plausible explanations include asteroids plowing into the rings and whipping up a cloud of plasma (which then levitates above the ring plane because of the magnetic field), and powerful lightning strokes that surge up from Saturn’s clouds, wallop the rings, and blast out jets of electrically charged dust as spokes. This latter theory holds promise, as spacecraft data also suggest that spokes happen with about the same frequency as the planet’s thunderstorms. Its magnetic field could transport electron beams from above these storms into the rings, where they charge the dust. Whatever the radial features are in the B ring, they have now succumbed to a flurry of new amateur sightings and CCD images — some with telescopes a lot more modest than the Harvard 9-inch refractor. When truth shocks us into believing, the fog of uncertainty lifts, allowing us to see more clearly with new eyes. D Stephen James O’Meara is a contributing editor of Astronomy who writes the magazine’s Secret Sky column each month.
October 2016 DISCOVER
65
SPECI A L BONUS SECTION
OUT THERE
To Catch a Shooting Star A renowned meteorite hunter turns his gaze to the sky as part of a growing network of fireball trackers. BY ERIC BETZ
→
Steve Schoner once spent 17 years looking for a single rock. He crisscrossed thousands of miles in hundreds of days walking the area around Glorieta Mountain in New Mexico. Along the way, he fell down a cliff, was confronted by a bear, hid from drug smugglers in the dark and saw more rattlesnakes than he could count. Most of the time, he hiked alone, watching the ground and listening for telltale beeps from a metal detector — sounds he hoped would lead him to a 40-pound (18 kilograms) asteroid remnant richly laden with yellow-hued stones. Schoner was among the most prolific meteorite hunters in the Southwest from the early 1970s until a rare brain disease nearly claimed his life in 2003. He searched then for what he still searches for now: billion-year-old chunks of space rocks left over from the chaotic upstart of our solar system. His slow uphill climb from disability now forces him to hunt meteors with a computer screen and an automated rooftop camera instead of wandering alone in a remote wilderness. The instrument is part of a growing network of fireball video recorders, which use black-and-white wide-angle cameras to capture the entire sky when triggered by celestial movement. These devices are giving astronomers new insights into Earth’s interactions with the space debris that surrounds us.
COSMIC DUST A meteoroid spends billions of years drifting about the solar system — either as part of a comet or asteroid, or even a chunk of the Moon or another planet — before it crosses paths with
66
DISCOVERMAGAZINE.COM
Earth and is violently ripped apart in the atmosphere. Rare martian rocks can be as young as a few tens of millions of years old, but common meteorites (the term for a space rock once it’s landed on Earth) are time capsules of planetary infancy dating back some 4.5 billion years. Small bits of rock are falling to Earth all the time. Estimates vary, but measurements indicate that thousands of pounds of these meteoric debris breach our atmosphere each day and find their way to the surface, where their organics play a role in earthly biology. Most of this cosmic dust is too small to create meteors. Sometimes the rocks are large enough to put on a show. Astronomers call these night-sky streakers “fireballs” when they flare brighter than Venus. And that’s the information New Mexico State University scientists are after. As the number of meteor observations increases, their All Sky Camera Network aims to create overlapping fields of view so that several cameras can catch the same fireball, allowing astronomers to find its speed and height. With sufficient imaging, researchers can calculate the meteor’s original orbit and help determine whether the object began life as a comet or an asteroid. “They’re hauling butt, so they’ve got a lot of energy,” says Bill Cooke, who runs NASA’s Meteoroid Environment Office at the Marshall Space Flight Center in Alabama. “A lot of people underestimate the amount of energy meteors have.” While an average fireball is typically about a millimeter to a centimeter in size, it’s entering Earth’s atmosphere at anywhere from 25,000 mph (11 km/s) to 160,000 mph (72 km/s).
The Chelyabinsk fireball lit up the skies over Russia in 2013. Asteroid expert Mark Boslough and colleagues used witnesses’ photos to re-create its path in this digital rendition made on a supercomputer.
Steve Schoner processes meteorites in his office, the former home of Pluto discoverer Clyde Tombaugh.
3-D SIMULATION: M. BOSLOUGH AND B. CARVEY; TAIL COMPOSITE: A. CARVEY; IMAGE: O. KRUGLOVA/SANDIA NATIONAL LABS. OPPOSITE: TAYLOR MAHONEY
“If that hits you, it’s like I shot you with a .357 magnum,” Cooke says. “That’s why we worry about orbiting debris so much. A particle smaller than a millimeter can go right through a space suit.” Part of the network’s initial funding and goals also stem from a desire to show the U.S. government’s satellites how to tell the difference between natural and man-made atmospheric explosions. In some cases, it even can help meteorite hunters like Schoner track down the rock if it survived the fall.
SHOOTING STAR SURVEY Schoner has been involved with this network from his home in Flagstaff,
Arizona, since 2012. And his camera isn’t just mounted on any rooftop; this is the former home of Pluto discoverer Clyde Tombaugh. So far, Schoner has caught a handful of fireballs. He used data from one event to try to hunt down the meteorite. Astronomers have labored to enlist a network of 100 rooftop cameras on homes across the country to watch for meteors, but due to budget cuts, the program was shifted to private servers. The data is still collected and stored for research and coordinating meteor fall trajectories, but it’s now run by a collaboration between amateurs and professionals. NASA runs its own search called the All Sky Fireball Network.
Cooke commands that project. He has some 15 cameras in use, and if he can find the funding, he’d like to implement many more. Whereas the All Sky Camera Network struggled because it relied on the user’s computer, Cooke provides citizen scientists with all the equipment needed, installs it, and then performs regular calibrations to make sure the measurements are precise. It’s highly effective and produces better science, but is also much more timeconsuming. In addition, he runs a companion effort with 14-inch Celestron telescopes pointed at the crescent Moon to watch for meteor flashes. “We can see a rock the size of a golf ball hitting the Moon with an amateur telescope on Earth,” Cooke says.
July/August October 2016 DISCOVER
67
SPECI A L BONUS SECTION
OUT THERE
THE GLORIETA PALLASITE As a teenager, Schoner developed a love for meteorites that would lead him to find hundreds of space rocks across the United States and abroad. His mother bought him his first meteorite as a birthday present in 1969. The young Schoner read a news story and contacted a hunter in Australia after residents in the town of Murchison watched a large fireball
68
DISCOVERMAGAZINE.COM
fall from the sky. He wanted to buy a piece. His father instead insisted he save his dollars for college. But when he returned home for spring break, his mother presented him with a package postmarked from Australia. “It was wrapped up in a twisted cellophane bag, and when I opened it up, I could smell the organic material oozing out of the meteorite,” Schoner says. She’d bought the carbonaceous chondrite for $7 a pound. (On eBay, thin sections from the Murchison meteorite now sell for hundreds of dollars per gram.) The gift emboldened Schoner, and, like generations of prior meteorite hunters, he set out on his own expeditions, combing the ground in known fall paths and speaking to locals when an object was actually seen falling from the sky. But he eventually found that
“Parting with that big pallasite was a mental trauma for me, even though it is only a big glorious rock. I labored for years, walking untold miles to find it,” Schoner says.
NASA’s fireball cameras can capture the entire night sky in one view, which helps tie events together using instruments around 50 miles (80 kilometers) apart. The cameras are composed of a wide-angle video recorder and a fan to prevent fogging.
even when you know the area where the meteorite fell, it can take years of searching to find what you’re after. At Glorieta Mountain, Schoner kept coming back because he believed his holy grail stone was out there. He was hunting a 40-pound chunk of pallasite that his mentor, meteor expert Harvey Nininger, first predicted should exist in the late 1930s. Whereas most meteorites are stony or iron, a pallasite comes from the boundary between an asteroid’s core and its surface. A pallasite has a rugged exterior, but when cut open, the stones show off like a gem, revealing brightly colored olivine crystals embedded throughout.
Steve Schoner combed a known fireball fall path for 17 years before he found this 44-pound (20 kilograms) meteorite.
BILL COOKE/NASA; STEVE SCHONER
It turns out the impacts correlate well with meteor showers on Earth. His scopes caught 21 flashes on the Moon in one night during the Geminid meteor shower in December 2010. He says the overall effort is teaching astronomers about the meteoric environment. And as NASA’s network expands, Cooke hopes to catch meteorites from the Taurids and Geminids. Meteors from those two showers are the only ones to breach Earth’s atmosphere slowly enough to survive all the way to the ground. Most storms of shooting stars stem from comet debris crossing Earth’s path; the Geminids are unusual because they come from an asteroid, 3200 Phaethon, which passes uncomfortably close to our planet. But what’s stranger still is that comets create shooting stars thanks to icy debris; astronomers don’t know how an asteroid could pull off such a show. One thought is that Phaethon started life as a comet, which is supported by its highly elliptical orbit. “Each year I look forward to these events that we might have a potential meteorite dropper,” he says. “The science value of that would be potentially immense. It’s kind of like a sample return mission, but it’s coming to us.” And the project has another even broader objective: informing the public. “We live in a world of 24/7 news, and if people see a bright light, they expect NASA to know what that is,” Cooke says. NASA often sends fireball footage to CNN and local TV stations following bright events.
NASA
In fact, hundreds of pounds of large meteorites had been pulled from Glorieta Mountain starting in 1884, but most were iron. Based on their composition, Nininger had told the then teenage Schoner that a large chunk of pallasite — about 40 pounds — should still be waiting in the dirt. The discovery of a lifetime finally came in 1997. Schoner had picked up a new metal detector and headed out to search for the stone. As he calibrated the instrument, he walked in a small area around his car to test how it responded. Then it went crazy. Elbow deep under the surface in a small crater-like depression, he found a 44-pound (20kg) meteorite exactly like the one Nininger had predicted. Schoner won’t say how much money he got, but only that he sold the stone to the well-known meteorite collector and dealer Darryl Pitt in a partial trade. Pitt took the risk of cutting the pallasite into slices and sold pieces all over the world. The largest section recently sold at auction for $82,000. “Parting with that big pallasite was a mental trauma for me, even though it is only a big glorious rock. I labored for years, walking untold miles to find it,” Schoner says. “I do not have a slice of it, and that is OK, as it is really only a rock — unlike any other rock, though.” For his part, Pitt says the pallasite as well as Schoner are two of the most interesting specimens he’s encountered in a long career chasing meteorites.
A FRESH FALL Schoner used funds from the meteorite, as well as cash from selling off property he owned in Flagstaff, to buy the Tombaugh house. He moved the small home to a lot at the base of Mars Hill, where the astronomer discovered Pluto. Tombaugh lived there with his wife and young children before moving to the White Sands Missile Range in New Mexico to help the military learn to track projectiles more precisely. Schoner began the renovation process, but not long after, he was hospitalized with
Asteroids Strike Anywhere, Anytime
Day (255)
Night (301)
NASA recently released a map of large meteor events, which conclusively shows impacts happen with no trends in location or timing.
profound brain trauma caused by a rare form of encephalitis — inflammation of the brain. Doctors thought he’d be permanently disabled. Schoner fought back and has regained much of his mental acuity, though he still struggles with stamina and simple math that once came easy to him. He makes his living now through his company, PetroSlides, where he creates thin sections of meteorites for researchers and collectors all over the world. He’s even had the opportunity to handle rocks from Mars and one potentially from Mercury. And he gets his fix of meteorite hunting thanks to his rooftop camera. He’s caught a handful of fireballs already, but one recent event has Schoner thinking the find of a lifetime might still be waiting. His camera caught a bright fireball October 4, 2014. The bolide lit up the skies over Flagstaff in the early morning hours and left a trail of lingering meteor smoke that mystified local residents, who took their photos to social media. On the sparsely populated Hopi reservation to the north, people said they felt the air shake and the ground move, rattling their windows. Schoner’s rooftop camera was the only one to capture the fireball on video.
1 10 100 1,000 10,000 100,000 1,000,000 Energy (gigajoules)
The instrument wasn’t dialed in enough to catch the exact fall path, but Schoner says he has a rough idea where it landed from talking to residents and comparing with online photos. Its likely placement on a Native American reservation means permission is required to search. He plans to mount an effort to find the stone, starting by getting the word out to let locals know what could be strewn across the ground. Schoner rates the rock’s potential significance by its “born-on” date, which stands out in his mind. Only 132 Mars meteorites have ever been found. Two fell in early October of different years. Like a meteor shower that returns at the same time each year, Schoner says he has a gut-level feeling that Earth crosses paths with a martian asteroid — a large rock kicked off the Red Planet in an ancient impact — around the same time each year. Statistically, Cooke says Schoner’s expectation of a martian meteorite is highly unlikely to hold up. But after Glorieta Mountain, the space rock hunter has shown that odds don’t mean much to him. D Eric Betz, a former associate editor at Astronomy, is an associate editor at Discover.
October 2016 DISCOVER
69
SPECI A L BONUS SECTION
OUT THERE
To Planet 9 — and Beyond! Our familiar solar system still hides some of the universe’s biggest mysteries.
→
Some astronomers have a knack for making it seem like humans have truly become masters of the universe. They built the Gaia space observatory, currently scrutinizing a billion stars to create the definitive map of the Milky Way. They detected ripples in space and time caused by black holes crashing into each other in a distant galaxy. They have analyzed the afterglow of the Big Bang — the
70
DISCOVERMAGAZINE.COM
very beginning of existence! — to measure the precise amount of matter and energy in the entire universe. And then there is astronomer Mike Brown of Caltech, always ready to deliver a dose of humility. His specialty is exploring the outer reaches of our solar system, a mere 1/1,000th the distance to the sun’s nearest star, and finding it full of shadowy unknowns.
Brown is most famous as the guy who discovered that Pluto is surrounded by a whole population of related objects. It was a revelation that prompted the International Astronomical Union to reclassify the former ninth planet as a “dwarf planet” and Brown to christen himself “@plutokiller” on Twitter. Recently, Brown and his colleague Konstantin Batygin made headlines again, this
CALTECH/R. HURT (IPAC)
BY COREY S. POWELL
TOP: CALTECH/R. HURT (IPAC)/WORLDWIDE TELESCOPE. BOTTOM: PATRICK T. FALLON
time by reporting convincing evidence of a true Planet 9 — a world some 5,000 times the mass of Pluto, orbiting even farther from the sun. Perhaps the most striking thing about Planet 9 is not that it (probably) exists, but that nobody has found it yet: a giant body, circling right in our celestial backyard, sight unseen. Masters of the universe? Ha. We don’t even know how many planets are in our own solar system. Brown likens his fumbling investigations of the realm beyond Pluto to the journeys of 16th-century European navigators. “Think of it the way you would if you were jumping on a ship going across the ocean and didn’t know what was going to be around the next corner,” he says. “I have some ideas of what might be there, but right now it’s really still a ‘there be dragons’ world that we don’t know anything about.”
SLOWLY, INTO THE DARK Exploring the outer solar system has always been a halting, painstaking process. Uranus, the first planet discovered in the modern era, was probably spotted by Greek astronomer Hipparcos in 128 B.C. but not recognized for what it is until William
Caltech’s Mike Brown (left) and Konstantin Batygin announced evidence — not proof — of a ninth planet in the solar system.
9
The aligned orbits of the six most distant solar system objects (purple) suggest Planet 9’s path.
Perhaps the most striking thing about Planet 9 is not that it (probably) exists, but that nobody has found it yet: a giant body, circling right in our celestial backyard, sight unseen. Herschel recorded it in 1781. Galileo apparently observed Neptune in 1613 but mistook it for an ordinary star; the planet wasn’t identified for real until 1846. Despite an intensive search for a hypothetical Planet X, pursued with fanaticism by wealthy eccentric Percival Lowell, it took another 84 years after Neptune’s discovery before Clyde Tombaugh discovered Pluto. Then 75 more years passed before Brown located the distant dwarf planet Eris and showed that Pluto is not alone. As Brown explains, there is a simple reason for the snail’s pace of discovery: “It’s a big solar system, and things get faint fast!” Solar illumination gets dimmer with the square of distance from the sun, and then any light reflected off a distant body likewise dims with the square of its distance from Earth. Put the two effects together, and the consequences are daunting. If you moved Pluto twice as far from the sun, its apparent
brightness would decrease by 2 to the 4th power — a factor of 16. Brown and a handful of colleagues have now pretty well scanned the zone around Pluto, out to around 5 billion miles from the sun, for large objects. A frozen ball known as V774104, currently the most distant solar system object known, is twice that far. Go just a little deeper, though, and all kinds of things could be circling about, invisible to even the best telescopes. For now, the evidence for Planet 9 comes solely from its gravity, not from its light. Starting about a decade ago, astronomers noticed odd patterns in the distant solar system. Brown and Batygin were especially struck by the orbits of six of the most extreme objects in the Kuiper Belt (the population of outer objects that includes both Pluto and Eris), all of which cluster on one side of the sky. They deduced that a large planet, roughly 10 times the mass of Earth, was lurking on the other side of the sun, its gravitational pull sweeping any smaller stuff out of the way. The pattern of clustering indicated a likely orbit for Planet 9. The fact that nobody had noticed it yet offered another clue: The planet must be on the darkest, farthest part of its looping path, possibly 100 billion miles away. That still leaves a lot of sky to examine. To visually track down his putative Planet 9, Brown is requesting 20 nights of observing time on the Subaru telescope in Hawaii, the only large instrument with a wide enough field of view to practically pull off
October 2016 DISCOVER
71
SPECI A L BONUS SECTION
such a search. Even if he gets his observing time (there’s a lot of competition), the project will take at least a year and a half. Brown has learned to be philosophical about these things. “There’s always a chance that the six times you’re looking for Planet 9, it happens to align with a star and you miss it,” he says, “but eventually we’ll find it, and then we’ll study it to death.”
THE GREAT BEYOND An important lesson from the discovery of Eris and the rest of the Kuiper Belt is that Planet 9 is certainly not alone. Astronomers now realize that the formation of the solar system was a messy, chaotic process that ejected all kinds of bodies out to the far fringes. Today, there are four giant outer planets. Planet 9, if it exists, is most likely a stillborn fifth giant planet, a smaller version of Neptune that got sent off on a very different evolutionary track. As Brown points out, it’s perfectly possible that six, seven or even more giant planets started to form before some of them were ejected. It is even more likely that smaller bodies — Mars size? Moon size? — are floating around on the fringes. “There’s a ton of stuff out there,” Brown says. And could Subaru spot a moon-size thing at a Planet 9-like distance? “Nope, nope, nope. Not a chance.”
Inner solar system
The future Large Synoptic Survey Telescope (seen in this artist’s conception) could find even more planets in its full-sky scans.
One way to extend human vision is to look for heat rather than light. Truly giant planets would retain a lot of thermal energy from the time of their formation, and therefore could show up in telescopes tuned to infrared rays or even colder millimeter waves. The WISE space telescope did a sky survey and found nothing, ruling out distant versions of Jupiter or Saturn. But Planet 9 would be too small and cool to show up in WISE’s detectors. Brown and the other outer explorers are much more jazzed about the Large Synoptic Survey Telescope (LSST), currently under construction atop Cerro Pachón in Chile. Starting in 2023, the LSST will perform extremely sensitive, repeated scans of the full night sky. It should eventually spot hundreds or even thousands of bodies out to the distance of Planet 9. Perhaps that bounty will include colder versions of Pluto, or a weird deep-freeze analog
Outer solar system
of Mars. The orbits of all those objects, in turn, could indirectly reveal the presence of even more distant worlds. “LSST will be great,” Brown gushes. “And I guarantee you, we’ll see patterns we didn’t anticipate. Then we’ll have to start looking to see what’s causing those other patterns.” Such bootstrapping will quickly hit a wall, however. There is no greater survey telescope planned after LSST — “a scary thing to think about,” Brown says — but we already know that the solar system keeps going far beyond that instrument’s limits. The Oort Cloud, a loosely bound flock of dormant comets, extends to at least 100 times Planet 9’s distance from the sun. There could be planet-size objects lurking out there as well. We have no way to see them, no way to detect them, not even any ideas on the drawing board about how to find them. When it comes to our celestial backyard, mystery — not mastery — is the name of the game. “It’s a big unknown,” Brown says. “I would love to just get in a spaceship and drive around the outer solar system, taking a look at this object and this object and seeing what’s really going on out there.” D Corey S. Powell, a contributing editor of Discover, also writes for the magazine’s Out There blog. Follow him on Twitter: @coreyspowell
Post–Kuiper Belt objects
Inner extent of Oort Cloud
The solar system’s a big place. More planet-size objects could lurk at Planet 9’s impressive distance from the sun, and no one knows what oddities might exist 100 times farther out in the enormous Oort Cloud.
72
DISCOVERMAGAZINE.COM
TOP: TODD MASON, MASON PRODUCTIONS INC./LSST CORPORATION. BOTTOM: NASA/JPL-CALTECH/R. HURT (SSC-CALTECH), ADAPTED BY COREY S. POWELL
OUT THERE
Join Discover magazine in Iceland!
Fire, Ice, & Aurora Adventure Explore the fascinating and diverse geology of Iceland on this trip of a lifetime — and marvel at magnificent auroral displays under dark northern skies. The editors of Discover and Astronomy magazines, working with TravelQuest International, have put together a wonder-filled travel itinerary that features:
Discover SCIENCE FOR THE CURIOUS
®
M AG A Z I N E
MARCH 18-25, 2017
• 5 nights of aurora viewing from the optimal observation location: Iceland, blessed with frequent and spectacular displays under vast night skies. • Iceland’s remarkably varied geology of fire — active volcanoes, steaming geysers, and natural hot springs — and ice — magnificent glaciers and sparkling icefields.
P28835
• Lively discussions of starry skies and northern lights, and tips on nighttime photography techniques.
For more information, visit DiscoverMagazine.com/trips-tours
Notes From Earth
The Judas Fish In Montana’s glacial lakes, biologists deploy an unusual weapon to defend native bull trout against an invader. BY JANINE LATUS
→
74
DISCOVERMAGAZINE.COM
Lake trout were introduced for sport fishing in western waterways, but they’ve outcompeted native species.
“We have to stop this ecological catastrophe, or Glacier’s native fishes will be lost for future generations.”
USGS research ecologist Clint Muhlfeld is part of National Park Service efforts to restore native bull trout in Glacier National Park.
encouraging anglers to take as many of the fish as they can catch. But on Quartz Lake, Muhlfeld and his team worked with the National Park Service to deploy a weapon they believe will greatly improve the bull trout’s odds: the Judas fish. The crews create these Judas fish by scooping up adult lake trout, cutting them open and inserting tracking devices. Then they sew the live fish shut and release them back into the lake. In autumn, the crews spend weeks clustered around the woodstove in a cabin on Quartz Lake, heading out at night on the nearly frozen lake, listening through headphones for the ping of sonic telemetry to track the Judas fish. It’s a 900-acre lake, yet over a two-week period around Halloween, all the adult lake trout gather at night at the fish equivalent of a giant singles bar, at the base of an avalanche chute where cobble and boulders provide safe havens for them to spawn. The Judas fish, living up to its biblical namesake, betrays the exact position. That’s when the biologists drop the nets and pull them in, hand-over-hand to the slaughter.
TOP: JOEL SARTORE/NATIONAL GEOGRAPHIC CREATIVE. BOTTOM: NOAH CLAYTON/USGS
It’s spring, but frost covers nearly half the boat ferrying Clint Muhlfeld and his crew across Quartz Lake, high in the mountains of Montana’s Glacier National Park. They hiked 6 miles to meet the flatbottomed skiff — which was strapped to the bottom of a helicopter and flown in — and carried nets, food, gear and gas because mules couldn’t cross the streams swollen with snowmelt. They’re here to tag an invasive species. The arduous trip is one of many biologists have made to the park’s lakes in recent years, part of an ongoing search-and-destroy mission to rein in one of the most pernicious aquatic threats in the West: lake trout. The sport fish, introduced in lakes over the past 100 years, have outcompeted native bull trout in many of them. In Glacier, Muhlfeld is determined to put an end to this slow-moving catastrophe. Over the years, lake trout have invaded eight of the park’s 12 connected glacial lakes west of the Continental Divide. Quartz Lake was number nine. “And that’s where we drew the line,” says Muhlfeld, an aquatic research ecologist with the U.S. Geological Survey and the University of Montana. “We have to stop this ecological catastrophe, or Glacier’s native fishes will be lost for future generations.” Biologists have tried various ways to rid Western lakes of these invaders, such as electrocuting their eggs or
CLOCKWISE FROM BOTTOM LEFT: CHRISTIAN GUY/IMAGEBROKER/ALAMY STOCK PHOTO; VIN D’ANGELO/USGS; CLINT MUHLFELD/USGS; VIN D’ANGELO/USGS; JOEL SARTORE/NATIONAL GEOGRAPHIC CREATIVE
Researchers catch adult lake trout (above) in Glacier National Park’s Quartz Lake (right) so they can surgically implant tracking devices (left). These tags lead crews to spawning grounds, where lake trout gather annually in large numbers. Then, the teams haul in the invasive species and slaughter them in an effort to aid native bull trout.
Never mind that it’s backcountrydark out and raining or sleeting or snowing, and headlamps provide the only light as the 25-foot boat bounces over white caps. They’re determined to get rid of the lake trout, or at least keep the population low enough that the native bull trout have a chance to thrive.
TROUT IN TROUBLE The Glacier watershed hosts about one-third of the natural lake habitat for bull trout in the country, but the fish themselves are increasingly scarce. Not only must they contend with lake trout, which consume native fish and compete with them for nutrients, now
rising temperatures could soon make the water too warm for the cold-loving bull trout to spawn. Counts are so low that they’re listed as threatened under the Endangered Species Act. The Judas fish has been a blessing for the bull trout of Quartz Lake. Over the five years of the project — the intensive phase wrapped up in 2014 — the team hauled more than 2,000 lake trout out of Quartz, finding fewer each year. The native bull trout population is exploding, with more nests and some of the highest spawning counts on record. “We got there in the nick of time,” Muhlfeld says.
But the battle isn’t over. In many other areas, lake trout are still winning.
A WATERY HAUL The team has now set its sights on Logging Lake, in another area of the park. It poses an even bigger challenge than Quartz: Here, lake trout have already taken over, and there are few bull trout left. The Judas fish alone won’t be enough. So Muhlfeld and his team are orchestrating a major intervention. In collaboration with park management, they’ve moved bull trout from Logging Lake to Grace Lake, which hasn’t been invaded yet. It lies above a 40-foot waterfall that lake trout can’t jump.
LAKE TROUT
Salvelinus namaycush Invasive species
BULL TROUT
Salvelinus confluentis Native species
October 2016 DISCOVER
75
Notes From Earth
The team had to move the fish by hand, hiking into the backcountry with a low-voltage wand to stun the fish. Then they scooped them up and loaded them into a backpack filled with about 35 pounds of oxygenated water and hiked 2 ½ miles uphill to Grace Lake. Fully aware that introducing fish to new environments is part of what started this cascade of problems in the first place, graduate student Benjamin Galloway spent two years evaluating the site. He found that the only fish species in the Grace Lake system are non-native, hybridized trout with no conservation value, so that isn’t a concern. And even if the introduced bull trout move back downstream, they will only land back in Logging Lake. Given a fresh start in the safe waters of Grace Lake, the relocated bull trout will likely thrive. “They’re iconic. They’re at the top of the food chain,” Muhlfeld says. “They’ve survived in the park for thousands of years.”
A GRAND EXPERIMENT Projects at Yellowstone Lake in Yellowstone National Park and at Idaho’s Priest Lake and Lake Pend Oreille are focused on removing lake
76
DISCOVERMAGAZINE.COM
Given a fresh start in the safe waters of Grace Lake, the relocated bull trout will likely thrive. trout in the hope that native fish will repopulate. But the Glacier team is going one step further. “We’re trying to also start a population where one didn’t exist, to hedge our bets over our success or failure in controlling lake trout in downstream waters,” says Chris Downs, the supervisory fisheries biologist and fisheries program manager in Glacier National Park. The risks seem minimal, and the alternative is to watch bull trout disappear from the ecosystem, he says. And so Muhlfeld’s team hiked, up and down between the lakes, carrying backpacks full of fish. In 2014, they relocated 125 bull trout from Logging Lake to Grace Lake. Then they took out their new boat, this one customized with a winch to pull in the mile of net, and harvested as many of the remaining lake trout as they could from Logging Lake. They took
measurements, checked the females for eggs, then “bonked them over the head, cut their air bladder and sunk them to the bottom of the lake,” Muhlfeld says, both to return the nutrients to the system and to keep from attracting grizzlies. In the spring, they returned for the juveniles. “The idea is that we overharvest the population from both ends, trying to turn off the faucet of reproduction and clean up the fish that sneak through or who have been there prior to suppression,” Muhlfeld says. “The hope is that doing both will cause the non-native population to collapse more quickly.” They don’t know yet how many of the bull trout they’ve moved have survived. They have an antenna at the Grace Lake outlet, so if any tagged fish leave, they’ll know. The hope is that the bull trout will thrive in Grace Lake and the fish will eventually return to Logging Lake. “It’s a grand experiment,” Muhlfeld says. “But had we done nothing to put them in a safe haven, there wouldn’t be any fish left for us to conserve.” D Janine Latus writes about the art, science and personalities of people who spark her curiosity.
CHRIS DOWNS/NATIONAL PARK SERVICE (2)
Researchers Jon McCubbins (above, foreground), Clint Muhlfeld (middle) and Andrew Lamont capture bull trout to relocate. McCubbins (right), a National Park Service biologist, hikes to Grace Lake with native fish in his backpack.
650+ Stores Nationwide
WOW SUPER COUPON • 1.3 GPM
Customer Rating
SUPER COUPON
1650 PSI PRESSURE WASHER LOT 69488
SAVE $70
comp at
$149.99 om or by calling stores or HarborFreight.c LIMIT 4 - Good at ourused with other discount or coupon or prior 800-423-2567. Cannot be from original purchase with original receipt. purchases after 30 days last. Non-transferable. Original coupon must be Offer good while supplies1/6/17. Limit one coupon per customer per day. presented. Valid through
R PE ON SU UP CO
16 OZ. HAMMERS WITH FIBERGLASS HANDLE CLAW
RIP
LOT 69006 60715/60714
LOT 47873 shown 69005/61262
20% OFF
ANY SINGLE ITEM
Limit 1 coupon per customer per day. Save 20% on any 1 item purchased. *Cannot be used with other discount, coupon or any of the following items or brands: Inside Track Club membership, Extended Service Plan, gift card, open box item, 3 day Parking Lot Sale item, automotive lifts, compressors, floor jacks, saw mills, storage cabinets, chests or carts, trailers, trenchers, welders, Admiral, Badland, CoverPro, Daytona, Diablo, Earthquake, Franklin, Grant’s, Holt, Jupiter, Lynxx, Maddox, Portland, Predator, Stik-Tek, StormCat, Union, Vanguard, Viking. Not valid on prior purchases. Nontransferable. Original coupon must be presented. Valid through 1/6/17.
YOUR CHOICE
SAVE 77%
3
$ 99
Customer Rating
comp at
$17.99
R PE ON SU UP O C
12,000 LB. ELECTRIC WINCH WITH REMOTE CONTROL AND Customer Rating AUTOMATIC BRAKE LOT 61256 61889 60813 shown
LIMIT 9 - Good at our stores or HarborFreight.com or by calling 800-423-2567. Cannot be used with other discount or coupon or prior purchases after 30 days from original purchase with original receipt. Offer good while supplies last. Non-transferable. Original coupon must be presented. Valid through 1/6/17. Limit one coupon per customer per day.
R PE ON SU UP CO
How Does Harbor Freight Sell GREAT QUALITY Tools at the LOWEST Prices? We have invested millions of dollars in our own state-of-the-art quality test labs and millions more in our factories, so our tools will go toe-to-toe with the top professional brands. And we can sell them for a fraction of the price because we cut out the middle man and pass the savings on to you. It’s just that simple! Come visit one of our 650+ Stores Nationwide. R PE ON SU UP CO
4-1/2" ANGLE GRINDER
Customer Rating
LOT 95578 69645/60625 shown
SUPER COUPON
FREE WITH ANY PURCHASE
7 FUNCTION DIGITAL MULTIMETER LOT 90899 shown 98025/69096
$
1645 VALUE
LIMIT 1 - Cannot be used with other discount, coupon or prior purchase. Coupon good at our stores, HarborFreight.com or by calling 800-423-2567. Offer good while supplies last. Shipping & Handling charges may apply if not picked up in-store. Nontransferable. Original coupon must be presented. Valid through 1/6/17. Limit one FREE GIFT coupon per customer per day.
WOW
SUPER COUPON
Customer Rating
3 GALLON, 100 PSI OILLESS PANCAKE AIR COMPRESSOR LOT 95275 shown 60637/61615
Customer Rating
SAVE 49%
30", 5 DRAWER TOOL CART
SAVE $230
$
LOT 69397 63308/61427 95272 shown
WE CARRY A FULL LINE OF GRINDING AND CUT-OFF WHEELS
• 704 lb. capacity
comp at
$399.99
LIMIT 4 - Good at our stores or HarborFreight.com or by calling 800-423-2567. Cannot be used with other discount or coupon or prior purchases after 30 days from original purchase with original receipt. Offer good while supplies last. Non-transferable. Original coupon must be presented. Valid through 1/6/17. Limit one coupon per customer per day.
R PE ON 1-1/4 GALLON SU UP HOME AND GARDEN CO
8
SAVE $179
4000 PEAK/ 3200 RUNNING WATTS 6.5 HP (212 CC) GAS GENERATORS
LOT 63079/63080/69729/69676 shown Customer Rating LOT 63089/63090/69675/69728 CALIFORNIA ONLY • 70 dB Noise Level
$
SUPER QUIET
289 comp at
99
$469
LIMIT 4 - Good at our stores or HarborFreight.com or by calling 800-423-2567. Cannot be used with other discount or coupon or prior purchases after 30 days from original purchase with original receipt. Offer good while supplies last. Non-transferable. Original coupon must be presented. Valid through 1/6/17. Limit one coupon per customer per day.
WOW SUP10ERFT.COUxPON 20 FT. OPY PORTABLE CAR CAN Customer Rating
LOT 60728/69034 63054/62858 shown
5
SAVE $61
RAPID PUMP® 3 TON HEAVY DUTY STEEL FLOOR JACK
$141.88
LIMIT 3 - Good at our stores or HarborFreight.com or by calling 800-423-2567. Cannot be used with other discount or coupon or prior purchases after 30 days from original purchase with original receipt. Offer good while supplies last. Non-transferable. Original coupon must be presented. Valid through 1/6/17. Limit one coupon per customer per day.
• 100% Satisfaction Guaranteed • Over 30 Million Satisfied Customers • No Hassle Return Policy
om or by calling our stores or HarborFreight.c t or coupon or prior LIMIT 4 - Good at used with other discoun 800-423-2567. Cannot be from original purchase with original receipt. days 30 after coupon must be es purchas last. Non-transferable. Original Offer good while supplies1/6/17. Limit one coupon per customer per day. presented. Valid through
• 350 lb. capacity
STEP STOOL/ WORKING PLATFORM
SAVE 65%
comp at
R PE ON SU UP CO
1.5 HP ELECTRIC POLE SAW
SAVE $29 Customer Rating
comp at
LOT 62515 66911 shown Customer Rating
LOT 69227/62116/62584 68048 shown
LIMIT 4 - Good at our stores or HarborFreight.com or by calling 800-423-2567. Cannot be used with other discount or coupon or prior purchases after 30 days from original purchase with original receipt. Offer good while supplies last. Non-transferable. Original coupon must be presented. Valid through 1/6/17. Limit one coupon per customer per day.
$205.99
R PE ON SU UP CO
• Weighs 74 lbs.
$98.62
LOT 68862/63190 62896 shown
comp at $ 99$15.99
R PE ON SU UP Customer Rating CO
7999
LIMIT 7 - Good at our stores or HarborFreight.com or by calling 800-423-2567. Cannot be used with other discount or coupon or prior purchases after 30 days from original purchase with original receipt. Offer good while supplies last. Non-transferable. Original coupon must be presented. Valid through 1/6/17. Limit one coupon per customer per day.
SAVE $106
comp at
$20.26
™
LIMIT 9 - Good at our stores or HarborFreight.com or by calling 800-423-2567. Cannot be used with other discount or coupon or prior purchases after 30 days from original purchase with original receipt. Offer good while supplies last. Non-transferable. Original coupon must be presented. Valid through 1/6/17. Limit one coupon per customer per day.
$
1199
comp at
YOUR CHOICE
$14.97
LIMIT 7 - Good at our stores or HarborFreight.com or by calling 800-423-2567. Cannot be used with other discount or coupon or prior purchases after 30 days from original purchase with original receipt. Offer good while supplies last. Non-transferable. Original coupon must be presented. Valid through 1/6/17. Limit one coupon per customer per day.
R PE ON SU UP CO
LOT 68496/61363 68497/61360/97582 68498/61359
$
SAVE 40%
$752.99
POWDER-FREE NITRILE GLOVES PACK OF 100
SIZE MED LG X-LG
SAVE 62%
$ 99 comp at
Customer Rating
• 5 mil thickness
Customer Rating
SAVE 39%
comp at
68498 shown
LOT 61280/63124 63145/95692 shown
29999
LIMIT 3 - Good at our stores or HarborFreight.com or by calling 800-423-2567. Cannot be used with other discount or coupon or prior purchases after 30 days from original purchase with original receipt. Offer good while supplies last. Non-transferable. Original coupon must be presented. Valid through 1/6/17. Limit one coupon per customer per day.
R PE ON SU UP CO Item
SPRAYER
™
$
SAVE $453
16999
$
On All Hand Tools
$
6999 comp at
$99
LIMIT 5 - Good at our stores or HarborFreight.com or by calling 800-423-2567. Cannot be used with other discount or coupon or prior purchases after 30 days from original purchase with original receipt. Offer good while supplies last. Non-transferable. Original coupon must be presented. Valid through 1/6/17. Limit one coupon per customer per day.
WOWWIRSUPELEERSSCOUSECPON URITY
SAVE 60%
ALERT SYSTEM
Customer Rating
LOT 93068 shown 69590/61910/62447
1999
comp at
$57.55
LIMIT 4 - Good at our stores or HarborFreight.com or by calling 800-423-2567. Cannot be used with other discount or coupon or prior purchases after 30 days from original purchase with original receipt. Offer good while supplies last. Non-transferable. Original coupon must be presented. Valid through 1/6/17. Limit one coupon per customer per day.
• 650+ Stores Nationwide • Lifetime Warranty
• Extends from 6 ft. to 8 ft. 10"
• HarborFreight.com • 800-423-2567
om or by calling our stores or HarborFreight.c t or coupon or prior LIMIT 6 - Good at used with other discoun 800-423-2567. Cannot be from original purchase with original receipt. purchases after 30 days last. Non-transferable. Original coupon must be Offer good while supplies1/6/17. Limit one coupon per customer per day. presented. Valid through
At Harbor Freight Tools, the "comp at" price means that the same item or a similar functioning item was advertised for sale at or above the "comp at" price by another retailer in the U.S. within the past 180 days. Prices advertised by others may vary by location. No other meaning of "comp at" should be implied. For more information, go to HarborFreight.com or see store associate.
History Lessons
A Profile of Plague We still have much to learn — and fear — from the ancient pestilence. BY HILLARY WATERMAN
→
78
DISCOVERMAGAZINE.COM
Over the centuries, Yersinia pestis (right), also known as plague, decimated Europe’s population many times over.
In a modern outbreak of plague, antibiotics and other treatments help us fare better. But it’s only been in the past decade that genome analysis has given the bacteria an evolutionary history, allowing us to link modern studies to past experiences.
disease. Yet Arizona State University historian and author Monica Green says it’s only been in the past decade that genome analysis has given the bacteria an evolutionary history of plague, allowing us to link modern studies to past experiences. Before these discoveries, she says, “I wouldn’t even teach a class on [it], because we didn’t know what it was.”
PLAGUE’S PARTICULARS Beginning in the mid-14th century with the Black Death and continuing
TOP: PICTORIAL PRESS LTD/ALAMY STOCK PHOTO. BOTTOM: EYE OF SCIENCE/SCIENCE SOURCE
In 2007, a wildlife biologist working for the National Park Service at the Grand Canyon discovered one of the collared mountain lions he had been tracking. The animal was dead. Concerned, he removed the lion’s body, took it home and performed a post-mortem examination. Within a week, he was dead, too. The cause of death for both: Yersinia pestis, commonly known as plague. The deaths, along with dozens of cases since, are a vivid reminder that the disease is alive and well. Y. pestis is a bacterium that lives in the bellies of fleas, which live on rodents, some of which, like rats, live near humans. Scholars estimate that plague killed up to half the European population during the Middle Ages, and for most the death was a painful, slow end. Although it has been an Old World menace for millennia, the disease hitchhiked to our shores on trade ships from Asia only in 1900. It caused a few rounds of epidemic before receding in 1925 to rural rodent populations, where it occasionally causes small-scale outbreaks. Last year, the Centers for Disease Control and Prevention reported 16 plague infections in the U.S., mostly in western states. Four of them were fatal. In a modern outbreak of plague, antibiotics and other medical advances help us fare better, but it remains a particularly nasty
CLOCKWISE FROM LEFT: SPL/SCIENCE SOURCE (2); ROBERT HOOKE/MICROGRAPHIA/NATIONAL LIBRARY OF MEDICINE; SPL/SCIENCE SOURCE
with successive waves, the deadly pestilence sucker-punched Europe’s population for 300 years, killing hundreds of millions of people in all — between one-third and one-half of the populace. No one knew what caused it. People had no knowledge of bacteria, so the panicky populace instead clung to specious theories about plague’s cause: bad smells, dank air, an imbalance of body humors, even God’s wrath. Contemporaries called it “The Great Mortality.” Bubonic plague in particular was recognizable by the horrifying appearance of buboes, blackened swellings in the victim’s groin and armpits. In its pneumonic form, the variation that killed the Grand Canyon mountain lion and ill-fated biologist, the infection goes straight to the victim’s lungs, dealing death within a day of the first appearance of fever and bloody
sputum. A victim could be healthy at breakfast, dead before sundown. Maritime trade routes had spread plague around the world by the 19th century. At that point, new microscopy technology and the germ theory of disease had revolutionized medicine. Researchers could now see the culprits and distinguish between similar diseases such as anthrax, cholera and, yes, bubonic
plague, which was isolated in 1894 the scholarly community, contended and named Yersinia pestis in honor that the Black Death had been a of Swiss microbiologist Alexandre dramatically more virulent infection Yersin. These diseases still posed a than the modern-day bubonic plague. major threat, but now doctors could These individuals argued that a different study them and develop science-based organism, perhaps anthrax or typhus, responses: Many cities in the U.S. originally caused the Black Death. and Europe established public health “With nothing but written documents,” boards, improved sanitation and Green says, “they were speculating instituted quarantines at the first sign about something they would never of disease spread. find evidence of. It could have been Finally, with the widespread use of anything. We just didn’t know.” penicillin in the 1940s, doctors Extent of area reached had an effective by Black Death way to treat the 1347 Area unaffected 1348 No reliable data disease, and 1349 interest in the 1350 1351 plague became 1352 more academic. By the 1970s, “plague deniers,” a vocal faction within
Alexandre Yersin (left) isolated the plague bacteria, which now bears his name, in a Shanghai hut (top left). The bacteria often travel in the bellies of fleas (above).
Finally, in 1998, a landmark study demonstrated that microorganisms could be — and usually are — preserved in the pulp of teeth after people die. This opened up new avenues of exploration in the burgeoning fields of paleogenetics and aDNA (ancient DNA) analysis. By 2011, geneticists, working with samples harvested by bioarchaeologists from a known plague cemetery in London, had fully sequenced the genome of 14th century Y. pestis. When they compared the ancient plague genome with that of modern plague and
October 2016 DISCOVER
79
History Lessons of plague, but it was humans who likely gave it the highways to travel. At that time, the extensive trade network known as the Silk Road ran throughout Eurasia. The trade routes were dotted with caravanserai, THE ROLE OF CLIMATE mass encampments where Since then, we’ve learned travelers could eat, lodge, even more about plague’s buy supplies and refresh past — and its possible their camels, a favorite future. In a 2015 paper in host of the fleas that the journal PNAS, Boris carry Y. pestis. Schmid of the University “Camels appear to get of Oslo proposed a less sick from plague than climate-based explanation humans, and thus might for the cyclical epidemics last longer before they that characterized the succumb,” Schmid says. disease’s presence in An infected camel could Europe. carry fleas far along Schmid’s team analyzed the route before dying. tree rings and growth The caravanserai were patterns from a variety of likely critical in plague juniper in the Karakorum dispersal. Mountains of Y. pestis’ While the disease Plague doctors wore masks to avoid the bad air they blamed for the disease. native western Central Asia. remains a modest threat Because the trees can live to in rural, undeveloped be 1,000 years old, Schmid could study areas, Green warns that our current samples from individual trees alive stable relationship with plague in during the Black Death. the developed world is only as good Statistical analysis revealed as our control of urban rodent a pattern: Each documented populations. Even then, outside of introduction of plague in Europe our cities, the occasional unfortunate was preceded by a significant climate brush with Y. pestis will occur, as event in Asia, such as a sudden shift the fate of the Park Service biologist in the annual monsoon pattern in the reminds us. mid-14th century, which pushed the Human populations are more northern border of activity from China mobile than ever, and our travel to Siberia. In every case, the Asian patterns combined with unchecked climate event preceded a major plague climate change only exacerbate the outbreak in Europe by almost exactly risk of outbreaks. If global warming 15 years. The pattern held for plague disrupts the status quo, we may again reintroductions via both land routes It was a cycle that often repeated see Y. pestis take deadly advantage of and maritime trade networks. itself. Schmid’s team pinpointed highly trafficked areas to wreak havoc The team reasons that large-scale three major pulses of plague on our population. “We will never climate fluctuations in Asia caused introductions in Europe, coinciding be able to fully let our guard down,” rodent colonies to collapse. Desperate with the continent’s three centuries Green says. D fleas sought new hosts, jumping of Black Death. Hillary Waterman is an anthropologist aboard passing animals, and plague Climate shifts created the right and science writer based in Maine. got a free ride across the continent. conditions for the westward advance
Climate shifts created the right conditions for the westward advance of plague, but it was humans who likely gave it the highways to travel.
80
DISCOVERMAGAZINE.COM
DEA PICTURE LIBRARY/DE AGOSTINI/GETTY IMAGES
placed it on the family tree, “Boom!” says Green. “It was directly related to the strain we see in the world today; we do not have reason to believe it was significantly more virulent. This was a game changer.”
CLASSIFIEDS T R AV E L
AMAZON RAINFOREST Award-winning lodge in Tamshiyacu-Tahuayo Reserve, shown to have the world’s greatest diversity of primates. Customized itineraries, daily departures. 1-800-262-9669. Visit: www.perujungle.com
COMPELLING
SCIENCE for curious minds. Newton’s apple. Edison’s lightbulb. Hawking’s astrophysics.
DO YOU HAVE A PRODUCT, OR SERVICE YOU WANT TO PROMOTE TO OVER
6 MILLION READERS?
ADVERTISE HERE
Subscribe to Discover magazine and see where your curiosity takes you. THE YEAR IN SCIENCE
Discover SCIENCE FOR THE CURIOUS
January/February 2016
100 TOP STORIES OF 2015
CONTACT STEVE MENI FOR INFORMATION, RATES, AND THE NEXT AVAILABLE ISSUE
888-558-1544 ext. 628
[email protected]
Antibiotic Breakthrough Biggest SETI Search Ever Human Gene Editing Limb Grown in a Lab The End of the Universe? . . . and More
PLUTO SHINES A big year for the little world.
10 issu
es
JUST $19 .95
Go to DiscoverMagazine.com or call 1-800-829-9132 Available in print or digital format.
ZOBRIST CUBE TM
20,000 Puzzles in a Box!
33 POLYCUBE PIECES & 52 PAGE CODE BOOK www.ZobristCube.com 1 (855) 962-7478 Ages 6 - Adult
20 Things You Didn’t Know About …
Making up one-fifth of all living mammal species and found on six continents, bats range from the insect-loving greater mouse-eared bat (top right), to fruit bats (top) and the poetically named Botta’s Serotine (above).
82
BY GEMMA TARLACH
1 It’s time for bats to come out of the shadows and get their due as an evolutionary success story: About one-fifth of all living mammal species are of the order Chiroptera (“hand-wing”), found on every continent but Antarctica. 2 It’s likely bats once flew over Antarctic skies, too. A 2005 study in Molecular Biology and Evolution found ancestral New World bats probably spread from the Americas to Australia about 42 million years ago via the now-frozen continent, which was then temperate. 3 Some of those far-flying early bats settled in New Zealand and evolved into three different species, which are the island nation’s only native land mammals. 4 New Zealand bats are often called pekapeka, the name the indigenous Maori people gave them. It might sound adorable, but Maori folklore associates the animals with death and calamity. 5 In fact, while bats are symbols of good luck in China, most other cultures side with the Maori. It’s probably because the animals are active at night, the opposite of naturally diurnal humans who have long associated darkness with danger. 6 Bats do pose some danger as vectors of disease, including rabies. Researchers suspect they may also carry Marburg, a relative of Ebola, and coronaviruses such as SARS. 7 Our perception of the threat may be exaggerated, though. In June, a review in Trends in Parasitology found that bats carry far fewer infectious diseases than rodents. 8 And they’re definitely not rodents. In the late 20th century, based on initial genetic research, bats were grouped with primates and flying lemurs in the superorder Archonta. 9 More recent genetic analysis — not yet universally accepted — places bats in the superorder Laurasiatheria, with a diverse bunch of other placental mammals including whales, dogs and giraffes. 10 Chiroptera’s fossil record is spotty because the earliest bats, like today’s species, had small, delicate skeletons that had to be buried in sediment immediately after death to be preserved. 11 We do know this: About 52.5 million years ago in what’s now Wyoming, early bat Onchonycteris finneyi was already capable of powered flight. 12 Bats are the only mammals with this trait; they also take to the skies differently than other flying animals. Unlike the more rigid wings of birds and insects, bat wings have multiple joints and move in and out as well as
up, down, back and forth with every stroke. 13 One thing bats do have in common with birds: According to research released in June, the outer layer of their skin contains a compound that enhances pliability — handy when flight depends on your flexible wings. No other mammal has this adaptation. 14 You might think echolocation is another defining Chiroptera trait, but not all bats send out sound waves that bounce off prey and potential obstacles to create a picture of their environment. 15 Fruit bats, for example, generally rely on their eyesight to find food. For decades, it was assumed they didn’t echolocate, and most don’t. But a 2014 study found three fruit bat species sometimes use a rudimentary method of echolocation: They make a clicking noise with their wings to navigate in darkness. 16 If not for the Vikings, we might call a bat a “rearmouse.” It derives from the Anglo-Saxon term for the animal, hreáðe-mús. As Norsemen moved into what’s now the United Kingdom, beginning in the ninth century, bakke, of Scandinavian origin, gradually replaced the word and evolved into bat. 17 “Rearmouse” persists colloquially today in areas of Great Britain that never fell under Scandinavian influence, including pockets of Wales and England’s southwest. 18 Bats jam. Seriously. A 2014 Science study found that when competing for food, Mexican free-tailed bats emit an ultrasonic signal that effectively blocks the sound waves another bat sends out to home in on an insect. The interference causes the rival to miss its target. 19 Something else that’s off-target: the myth that bats get tangled in long hair. Some scholars trace the notion to an early Christian edict that women must cover their heads because their hair attracted demons. Already associated with devilish things, bats were assumed also to have a thing for hair. 20 One more fiction that makes us batty is the whole vampire thing. Only three of the more than 1,200 bat species are sanguivorous. Any bat you meet is far more likely to eat a mosquito or pollinate fruit than go for your jugular. D In memory of Catherine Chenoweth, a friend of bats and of Senior Editor Gemma Tarlach.
DISCOVER (ISSN 0274-7529, USPS# 555-190) is published monthly, except for combined issues in January/February and July/August. Vol. 37, no. 8. Published by Kalmbach Publishing Co., 21027 Crossroads Circle, P.O. Box 1612, Waukesha, WI 53187-1612. Periodical postage paid at Waukesha, WI, and at additional mailing offices. POSTMASTER: Send address changes to DISCOVER, P.O. Box 62320, Tampa, FL 33662-2320. Canada Publication Agreement # 40010760. Back issues available. All rights reserved. Nothing herein contained may be reproduced without written permission of Kalmbach Publishing Co., 21027 Crossroads Circle, P.O. Box 1612, Waukesha, WI 53187-1612. Printed in the U.S.A.
DISCOVERMAGAZINE.COM
FROM TOP: INGO ARNDT/NATUREPL.COM; HANS CHRISTOPH KAPPEL/NATUREPL.COM; BROCK FENTON
Bats
GEAR, PHOTOS, FLIGHT, PERSPECTIVE, AND THE FUTURE!
If you’re a multirotor hobbyist, have questions about drone regulations, want to capture jaw-dropping aerial videos, or wonder how drones help in research, humanitarian aid, and our everyday lives, you’ll find it in all-new Drone360. In six stunning issues a year, you’ll find: • Drone and equipment reviews. • Photo, video, and flying tips from the pros. • The latest on rules, regulations, and licensing. • How-to tips for getting and keeping your drones working. • Insightful interviews with innovators and thought leaders.
www.Drone360mag.com March/April 2016
5 QUESTIONS WITH UAS EXPERT GRETCHEN WEST
AUTOMATING THE FUTURE OF FIGHTING p.54
WOMEN TAKE CENTER STAGE WITH UAS
p.70
WHEN AIRCRAFT EXPLORING MAKING RULES FIGHT FOR SPACE THE DEPTHS FOR DRONES everyone loses p.46 with ROVs p.76 ain’t easy p.64
It’s everything you need to get in the air!
SUBSCRIBE NOW AT DRONE360MAG.COM Drone360 is a trademark of Kalmbach Publishing Co.
70% ER
WASHINGTON UNIVERSITY IN ST. LOUIS
1.
Energy and Human Civilization
2.
Energy: Forms and Conversion for Use
3.
Heat: The Transfer and Flow of Energy
4.
Electricity: Ultimate Energy Converter
6
off
Taught by Professor Michael E. Wysession LECTURE TITLES
ER
LIM
D TIME OF R FE
OR
D
E IT
The Science of Energy: Resources and Power Explained
BY O C TO
B
5.
Chemical Energy, Biomass, and Photosynthesis
6.
Coal: Convenient, Energy-Dense Fuel
7.
Petroleum: Chemistry, Retrieval, and Use
8.
New Petroleum Directions
9.
Fossil Fuel Energy: Issues and Concerns
10. Understanding Carbon Dioxide 11. The Science of Nuclear Power 12. The Nuclear Fission Fuel Cycle 13. Sunlight: Inexhaustible Energy Source 14. Solar Power and Electricity 15. Wind Power and Electricity 16. Hydroelectric Power: Electricity from Water 17. Biofuels: Biodiesel and Ethanol 18. Geothermal Energy 19. Energy Storage Technologies 20. Energy Needs for Transportation 21. Energy Efficiency: Technologies and Trends 22. Energy Sources: Economics and Politics 23. Probable and Possible Future Energy Sources 24. Energy Trends: Planning for the Near Future
Explore How Energy Powers Our Lives Energy is, without a doubt, the very foundation of the universe. It’s the engine that powers life and fuels the evolution of human civilization. Yet for all its importance, what energy is and how it works remains a mystery to most non-scientists. In the 24 lectures of The Science of Energy: Resources and Power Explained, award-winning Professor Michael E. Wysession of Washington University in St. Louis presents a scientific investigation into energy sources that power our world. A thorough, understandable introduction to the fundamentals of different energy sources that we often take for granted, this marvelous window into the inner workings of energy will illuminate the world around you.
Offer expires 10/06/16
THEGREATCOURSES.COM/9 DISC 1-800-832-2412
The Science of Energy: Resources and Power Explained Course no. 1363 | 24 lectures (30 minutes/lecture)
SAVE UP TO $190
+$10 Shipping, Processing, and Lifetime Satisfaction Guarantee
Priority Code: 132573 For over 25 years, The Great Courses has brought the world’s foremost educators to millions who want to go deeper into the subjects that matter most. No exams. No homework. Just a world of knowledge available anytime, anywhere. Download or stream to your laptop or PC, or use our free mobile apps for iPad, iPhone, or Android. Over 550 courses available at www.TheGreatCourses.com.