How dinosaurs conquered the world Brute force or sheer luck?
p72
www.knowledgemagazine.in
Volume 3 Issue 3 April 2013 `100
Life
SCIENCE • HISTORY • NATURE • FOR THE CURIOUS MIND Freep!r
Mar-A med le the Blue wha r inside calenda
• What is it? • Where does it come from? • And what does it mean?
R.N.I. MAHENG/2010/35422
A Robot With Muscles, Bones and Tendons? p46
10 Unintentional Scientific Discoveries p56
The Ranthambhore Tigers by Valmik Thapar p78
On the cover history Science
DINOSAURS
HOW DINOSAURS CONQUERED THE WORLD
HISTORY
Brute force or sheer luck?
The dinosaurs’ rise to dominance was once thought to be driven by brute force. But, says Dr Darren Naish, that’s far from the truth
GETTY, DREAMSTIME
HOW
54
FREE !
Dinosaurs beat the competition, but it almost didn’t happen…
April 2013
Mar-Apr ed them Blue whaler inside calenda
The dominance of the dinosaurs during the mesozoic era was nothing more than a fluke
ACCIDENTS
ACCIDENTAL DISCOVERIES
Charles Goodyear demonstrates how his discovery of vulcanised rubber came about by chance
8
VULCANISED RUBBER
9
VASELINE
HISTORY
In its natural state, rubber can rot and smell. For many years, American inventor Charles Goodyear tried to make a more durable substance. In 1839, he finally found success – by accident. Inadvertently brushing rubber powder and sulphur from his hands, it landed on a hot stove. The melting rubber reacted with the sulphur and became vulcanised – leading to Goodyear becoming a pioneer in the tyre industry.
WILL HAPPEN
Scientific discoveries don’t always happen by design. Nige Tassell reveals 10 breakthroughs in which serendipity played its part
1
4
TEFLON
DUPONT, ALAMY, SCIENCE PHOTO LIBRARY, SCIENCE & SOCIETY PICTURE LIBRARY, MARY EVANS PICTURE LIBRARY, GETTY X3, PRESS ASSOCIATION X2
In 1938, a young American scientist called Roy J Plunkett was researching new refrigerants for the DuPont Company and was storing tetrafluoroethylene gas in cylinders at low temperatures. When he opened the cylinders, the gas had disappeared, but the containers still weighed the same. Intrigued, Plunkett sawed a cylinder in half and a white powdery substance fell out. Finding it to be resistant to heat and that few other substances would stick to it, he realised the substance – polytetrafluoroethylene – could have widespread use.
One accidental discovery that has saved millions of lives came about as a result of bad housekeeping. In 1928, London-based Scottish scientist Alexander Fleming accidentally left a tray of staphylococcus bacteria uncovered. After a few days, bacterial growth was visible, save for a patch of mould that was stopping the bacteria’s spread. A substance produced by the mould, dubbed penicillin by Fleming, was subsequently found to kill off much harmful bacteria and became the world’s most used antibiotic.
6 2
3
5
CELLOPHANE
In 1900, Swiss engineer Jacques E Brandenberger was eating lunch when a fellow diner spilled some wine, causing the tablecloth to be replaced. Brandenberger decided to invent a waterproof tablecloth, but the application of a liquid viscose made the covering too stiff. The coating did, however, peel off as a piece of transparent film. A new product, with strong commercial potential, was born.
56
In 1859, a 22-year-old Brooklyn chemist called Robert Chesebrough visited the Pennsylvanian oil fields, eager to break into the profitable industry. The oil workers told him about a sticky substance called ‘rod wax’, a by-product of the extraction process that often caused the drilling rigs to seize up. A redeeming feature was that it seemed to speed up the healing of cuts and burns. After ten years of testing, Chesebrough managed to extract usable petroleum jelly. Vaseline was born.
VIAGRA
In the early 1990s, British scientists employed by the Pfizer pharmaceutical company were carrying out tests on a new compound aimed at treating angina. The trials were unsuccessful, but many of the participants reported experiencing penile erections. After further trials, Pfizer took the drug Sildenafil citrate – by now branded as Viagra – to market. By 2000, Viagra accounted for 92 per cent of worldwide sales for prescribed erectile dysfunction pills.
SACCHARIN
Life
• What is it? • Where does it come from? • And what does it mean?
PENICILLIN
A Russian chemist called Constantin Fahlberg was, in 1878, working at Johns Hopkins University in Baltimore, analysing the chemical compounds of coal tar. One day, he neglected to wash his hands when he left work and, eating his dinner at home, discovered that the compound sulphamine benzoic that remained on his fingers had a sweet taste. He quickly – and privately – applied for patents in several countries and saccharin made him a wealthy man.
Volume 3 Issue 3 April 2013 `100
SCIENCE • HISTORY • NATURE • FOR THE CURIOUS MIND
72 How Dinosaurs Conquered The World
history
p72
www.knowledgemagazine.in
DINOSAURS CONQUERED THE WORLD
April 2013
7
DYNAMITE
The Swedish chemist Alfred Nobel owned a factory manufacturing nitroglycerin, an explosive deemed too unstable for widespread use. One day in 1867, he dropped a vial of it on the ground, but was intrigued when it didn’t explode, possibly because it had mixed with sawdust on the floor. When Nobel added a further stabiliser – silica known as kieselguhr – mass production of reliable gunpowder could begin.
10
THE MICROWAVE OVEN
In 1945, Percy Spencer, an employee of the American defence contractor Raytheon, was standing in front of a magnetron when the chocolate bar in his pocket melted. Intrigued, Spencer placed some popcorn in front of the tube. It instantly popped across the room. The commercial potential of the discovery was pounced upon; within two years, Raytheon were marketing the first microwave oven.
SUPER GLUE
In 1942, Kodak employee Harry Coover was making plastic gunsights for military planes, but the solution he created – later named cyanoacrylate – was far too sticky. A decade later, a colleague developing jet fighter canopies used the discarded solution and its phenomenal gluing powers were rediscovered.
April 2013
57
April 2013
56 Accidents Will Happen 10 accidental discoveries you won’t believe happened
science
ROBOTICS
R.N.I. MAHENG/2010/35422
A Robot With Muscles, Bones and Tendons? p46
Some of evolution’s finest designs are being mimicked to build robots with incredible abilities. Duncan Graham-Rowe takes a close look at the machines that can climb vertical walls, sprint and eat raw sewage…
ay the word ‘robot’ and it’s hard not to think of shiny, mechanical droids, rolling around busily beeping and whirring like R2-D2. But the fact is, if robots are ever to stand a chance of becoming a major part of our world, they are going to have to first lose the dustbin-onwheels image and take on something altogether more organic. After decades of being ingrained into our psyche, the classic mechanical notion of how robots should look, move and function is now undergoing a radical transformation as roboticists – from universities and private companies alike – are increasingly taking inspiration from the animal kingdom. After all, why try to engineer solutions to problems that Nature has already spent millions of years of trialand-error perfecting? So, out goes the wheel, the gear and the battery pack, to be replaced by leg, muscle and stomach. This transformation is giving rise to a new class of robot that is faster, more agile and dexterous, and ultimately better equipped to cope with life among us. These ‘biobots’ could even end up sitting down to dine with us. But the real prize is the growing hope and belief that mimicking biological systems could dramatically accelerate the quest for true artificial intelligence. By interacting with the world like humans, robots will finally start to think like us. Here we take a look at five pioneering biobots that are leading the charge in this merging of E biology and robotics.
PATRICK KNAB
S
46
>BASED ON
HUMAN BEING
ECCEROBOT The robot with muscles, bones and tendons… and the ability to learn If you were to remove someone’s skin, as though creating a Gunther von Hagens exhibit, what you’d be left with is something resembling Eccerobot. While most androids are made of conventional mechanical joints and precision motors covered with a rubbery skin-like coating to make them look human, Eccerobot’s human-like qualities are more than skin deep. “Eccerobot has a torso and arms made up of bone-like pieces – many copied from Gray’s Anatomy,” says Prof Owen Holland, a roboticist at the University of Sussex who is a lead investigator on the project. “These bones are held together and moved by soft tissues in the form of rubber bungees connected by cords to the spindles of electric motors.” Winding or unwinding the cords stretches or relaxes the bungees, just as we stretch or relax our muscles. These artificial muscles then pull on the thermoplastic bones to create movement. The result is movements that have a human quality about them, says Holland. “When a traditional robot moves a joint, it has no effect on the rest of its body,” he says. This is why they move in such a characteristically stiff ‘robotic’ fashion.
But with Eccerobot (Embodied Cognition in a Compliantly Engineered Robot to give him his full name), whenever part of him moves, the movement is distributed throughout the whole body. The consortium of robot labs across Europe that developed Eccerobot is currently looking at how this sort of musculoskeletal robot could be used in manufacturing. It is also creating a boysized version of Eccerobot, called Roboy, who unlike his older sibling, will have legs and the ability to walk. The hope is to have a prototype strutting around by March of this year.
10 Unintentional Scientific Discoveries p56
The Ranthambhore Tigers by Valmik Thapar p78
Artificial tendons, muscles and bones make Eccerobot move in an eerily human manner
HOW IT WORKS Muscles, tendons and a skeleton create a compliant, human-like form of movement. By mimicking human motion, the hope is to create robots with richer data streams from their sensors, ultimately making them smarter.
MIND AND BODY One of the main motivations behind Eccerobot’s development was to explore the link between movement and cognitive ability. By combining data from sensors across the robot’s body with information from his camera, or ‘eye’, he can learn how movements in one part of his body will affect another and what interactions with the outside world, such as grasping a coffee cup, ‘feel’ like. This is a form of low-level intelligence, says Professor Rolf Pfeifer, director of the University of Zurich’s Artificial Intelligence Laboratory and another of the lead investigators on the project. “There is a tight connection between sensory-motor processes and cognition, thinking and intelligence,” says Pfeifer. For a robot butler to be of any real use, it would need to be able to respond to different situations and interact with its environment. Eccerobot provides the first clues as to how that could be achieved.
Life
science
April 2013
46 Rise Of The Biobots
A robot with muscles, bones and tendons? It is not science fiction, but a soon emerging reality AN EXCERPT FROM A BOOK YOU SHOULD READ
nature
NATURE
INSIDE THE PAGES
The Origin Of Life
TIGERS MY LIFE Ranthambhore and Beyond
I
tiger of Ranthambhore. A typical day spent with him comes from my records of March 1984, ‘Genghis moves into this patch of long grass at about 11.30 am after consuming the remains of a wild boar piglet that he had killed the previous evening. He sleeps in the shade of the grass till 2.30 pm, when a group of sambar appears on the shore, slowly moving towards him. As they get close, he erupts into a charge, chasing past us and slamming his forepaws into the earth. He screeches to a halt in front of our jeep. He snarls at us, annoyed, but it has been an amazing display of breathtaking power, strength, and speed. Later, he quietly crosses to Malik Talao, and stands motionless in the tall grass, watching sambar wade through the waters of the lake. His eyes settle on a target and he races out through the grass, scattering the deer in all directions. Some end up in deeper April 2013
78 Inside The pages
p32
Life On Other Planets p38
By Valmik Thapar In his 35 years of engagement with the Ranthambhore tigers, Thapar recounts his favourite passage from his book was certain that the 1980s would be the most amazing decade in the life of the tiger. It was in 1983 that we encountered the great feeding behaviour between adult tigers near Malik Talao, where for the first time I witnessed real aggression as two tigers tugged at both sides of a carcass in their effort to own it, and the forest reverberated with the roars of tigers, stunning my senses like never before. This was the beginning of Noon’s reign around the lake and over the next decade, she became one of my favourite animals. It was at the beginning of her regin in late 1983 that we encountered the remarkable male tiger, whom we ended up calling Genghis. He exploded across the Ranthambhore lakes, and his activities during the one season he was around were legendary. He was unique, and I spent a lot of time with him, predicting his every move. To me, he was the great thinking
GETTY
on the cover: Thinkstock, shah rogers photography, David shale, getty, 123rf.com
SCIENCE
E 79
What Is The Meaning Of Life p40
Conservationist Valmik Thapar recounts the golden decade at Ranthmabhore National Park April 2013
3
Contents LIFE
FEATURES ON THE COVER
32 The Origin Of Life
APRIL 2013
32 The Origin Of Life Early Earth may have looked like Hell, but it was a great place to live
The story of the greatest of miracles – how life came to be on Earth in the first place
38 Life On Other Planets
How close are we to finding out if we’re all alone?
40 What’s The Meaning Of Life?
History History Nature nature history nature science
patrick knab, Science photo library x3, Science & society picture library, corbis, gunter zeisler, Musee Guimet
science
Will we ever understand whether life has a purpose? If so, what might it be?
4
ON THE COVER
46 Rise Of The Biobots
Scientists across laboratories are creating robots with incredible human-like abilities
52 Asoka And His Legacy
Himanshu Prabha Ray decodes Emperor Asoka’s remarkable vision and belief system that sets the precedent for future leaders of India ON THE COVER
56 Accidents Will Happen
10 of the best-known inventions, which came into being more by accident than design
58 Portfolio: Wild Orchids
Award-winning photojournalist Christian Zeigler brings to life the bright colours and beguiling looks of the wild orchids
22 Update
Have we found a faster way to communicate?
Herpetologist Romulus Whitaker tells of his experience on the misunderstood crocodile species - the Gharial ON THE COVER
72 How Dinosaurs Conquered The World Find out how dinosaurs rose to the top of the food chain during the mesozoic era ON THE COVER
An excerpt from Valmik Thapar’s book, Tigers My Life, which looks at the tigers of Ranthambhore National Park
82 The Big Idea: Evolution
Robert Matthews investigates how Darwin’s theory of evolution has ignited the 150 year-old row between science and the church April 2013
Accidental Discoveries I didn’t mean to do that...
64 From The Jaws Of Extinction
78 Inside the Pages
56
52
Asoka An emperor ahead of his time
78 Inside The Pages
Regulars
Genghis was the only tiger in Ranthambhore that sprinted like a cheetah
8 Think n Win
Our Life special crossword is bound to get your DNA in a twist
10 Q&A
Saddle up the horse of questions and ride out onto the plain of answers
16 Snapshot
Three more outstanding photographs to entertain and educate
81 Edu Talk
10 Q&A
How much power do the bigger cities consume?
Naveen Chopra of the The Chopras, an overseas education consultancy, talks about paying attention to the student’s holistic needs
96 Gadgets
Our science app special is bound to make you feel like a nerd albeit a cool one
UPDATE 22 Latest Intelligence
Find out how neutrinos could revolutionise our mode of communication
26 Comment & Analysis
46
Biobots We have come a long way from C3PO and R2D2
64 The Gharials
Has its slender snout led to its decreasing numbers in the wild?
Should we consider drilling into a supervolcano to find out what lies beneath?
28 World In Context
Celebrated social commentator Gurcharan Das talks about the rising power and responsibility of the new aam admi
Resource 88 Reviews
A book that takes on the scientific adventure of the Universe within
98 The Last Word
The next step in evolution will be triggered by humans opines Renee Borges
ERED THE WORLD
CONQU HOW DINOSAURS luck? p72 Brute force or sheer
zine.in www.knowledgemaga
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Volume 3 Issue 3 April 2013 `100
Life
FOR THE CURIOUS HISTORY • NATURE •
MIND
• What is it? e from? • Where does it com n? • And what does it mea
R.N.I. MAHENG/2010/35422
A Robot With Muscles, p46 Bones and Tendons?
10 Unintentional s p56 Scientific Discoverie
5
The Ranthambhore Tigers by Valmik Thapar p78
inbox From the editor What is LIFE and how did it originate? Isn’t this as ultimate as questions can get? And science, philosophy, religion owe their existence to the pursuit of this puzzle. In this special edition of BBC Knowledge, we bring to you the latest that is known about this mystifying phenomenon. Do read our 16-page special starting from page 30. The theory that intrigues me the most these days is the Panspermia Theory, which suggests that life came to Earth from outer space. That once the seeds of life find the right environment on a planet, they become active and the process of evolution begins. Now this may not be the foremost theory out there but it sure is the most awe-inspiring. By accident or by intelligent design, it seems life does find a way. See our photo feature on the Orchids, and especially the Red Beak Orchid on page 58; when its seeds are ready to disperse, this plant turns black as to not attract attention of grazing animals. And our planet is teaming to the core with such wonders. But our issue is not just limited to the wonders of the natural world, also read the feature on Accidents Will Happen (p56) to know how many of modern world’s essential ingredients came about out of sheer luck… and mistakes. And artificial life is finding a way too, through technology – as you will discover by reading our feature on Biobots (p46). Also in this edition - a must-read is the excerpt from renowned tiger conservationist Valmik Thapar’s book as well as the feature on Gharials by the world famous herpetologist Romulus Whitaker. Enjoy.
Mrigank sharma (India Sutra)
6
April 2013
Christian Ziegler is an award-winning international photographer and the founding fellow of the International League of Conservation photographers. In this issue, he highlights the deceptive beauty of the wild orchids. See page 58 Romulus Whitaker is a world-renowned herpetologist and wildlife conservationist. Whitaker’s boyhood fascination with snakes has developed into a glorious career. Winner of the Whitley Award and the Associate Laureate Rolex Awards for Enterprise, he has authored several articles and books on reptiles, including Snakes of India - The Field Guide. In this issue, he speaks about the lesser known Gharials. See page 64 Valmik Thapar is India’s foremost tiger conservationist. He is an author of 21 books on tigers, wildlife and Africa. In this issue, we present an excerpt from his book Tigers My Life Ranthambore and Beyond, where he recounts his favourite years and tigers at the Ranthambore National Park. See page 78
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Gurcharan Das is an author and social commentator. He is the author of two international bestsellers The Difficulty of Being Good: On the Subtle Art of Dharma and India Unbound. In this issue, he redefines the aam admi and the need for a strong liberal state. See page 28
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7
Think nwin Solve the clues and unravel the mysteries of Life
Life?
What is the
meaning of
Across 3 The hypothesis that life exists throughout the universe and is distributed by meteoroids and asteroids (10) 7 Homo _____ : common ancestor of humans and Neanderthals (10) 8 One of the first and simplest of multi-cellular animals (7) 10 One of the simplest and earliest animals exhibiting bilateral symmetry (9) 11 First animals to have temporal fenestra, a pair of holes in their skulls behind the eyes (11) 14 ___ worms : One of the first creatures having a circulatory system with a heart (5) 18 Area in Western Australia where one of the world’s oldest fossils was found (8,4) 20 Famous 3.2 million year old hominid fossil named after a Beatles song (4) 22 The earliest known life existed in this geological era (9) 23 The first bipedal ape (12) 24 Anthropoid apes and human beings (10) 26 Darwin’s famous theory (9)
alamy, thinkstock
Down 1 First animals with a body of definite form and shape (10) 2 20 Across was found in this
African country (8) 4 Y-Chromosomal ____ : The most common ancestor from whom all male human Y chromosomes are descended (4) 5 The largest land animal is a member of this dinosaur family (9) 6 Geological age in which the first anatomically modern humans made an appearance (6,11) 9 Scientists believe that life on earth first evolved around ___ billion years ago (4) 12 Process by which life arises from inorganic matter (11) 13 Dinosaurs became extinct around the end of this geological era (8) 15 Element crucial to evolution and life (6) 16 Along with Stanley Miller he conducted an experiment that demonstrated how organic molecules could have spontaneously formed from inorganic material (6,4) 17 Indonesian island on which 12,000 year old fossils of a hobbit like creature were found (6) 19 An organism whose cells contain complex structures enclosed within membranes (9) 21 Birds evolved from these famous prehistoric creatures (9) 25 Life’s building block (3)
How to enter: Post your entries to BBC Knowledge Editorial, Crossword No.14, Worldwide Media, The Times of India Bldg, 4th floor, Dr Dadabhai Navroji Road, Mumbai 400001 or email
[email protected] by April 10, 2013. Entrants must supply their name, address and phone number. How it’s done: The puzzle will be familiar to crossword enthusiasts already, although the British style may be unusual as crossword grids vary in appearance from country to country. Novices should note 8
April 2013
SOLVE & W
gift vouc
IN
hers wort
`F500
rom www.hitp lay.in
Crossword NO.14
Your Details Name: Age: Address: PinCode: Tel: School/Institution/Occupation: Email:
that the idea is to fill the white squares with letters to make words determined by the sometimes cryptic clues to the right. The numbers after each clue tell you how many letters are in the answer. All spellings are UK. Good luck! Terms and conditions: Only residents of India are eligible to participate. Employees of Bennett Coleman & Co. Ltd. are not eligible to participate. The winners will be selected in a lucky draw. The decision of the judges will be final.
Solution of crossword NO. 13 Announcing the winners of Crossword No. 13
Sidharth Bhatla Haryana • N. Manoj Bangalore
h
QA &
Your Questions Answered
[email protected]
HIGHLIGHTS EWhat would happen if all the coral reefs disappeared? p11 E Have any planets other than
Earth showed signs of global warming? p12 E How do chicks breathe when in the egg? p13 E Do ants have feelings? p15
Expert PANEL Susan Blackmore
Susan is a visiting psychology professor at the University of Plymouth. Her books include The Meme Machine.
Dr Alastair Gunn
Alastair is a radio astronomer at the Jodrell Bank Centre for Astrophysics at the University of Manchester.
Robert Matthews
After studying physics at Oxford, Robert became a science writer. He’s a visiting reader in science at Aston University.
Gareth Mitchell
How much power do the biggest cities use? London, with a population of around 8 million, uses electrical power at an average rate equivalent to the output of around five nuclear power stations. But size isn’t everything. Dubai, where temperatures regularly reach over 40°C, is home to some of the most power-hungry people in the world. They consume it at a rate equivalent to the output of four nuclear power stations – while having barely one-quarter the population of London. RM
Starting out as a broadcast engineer, Gareth now writes and presents Digital Planet on the BBC World Service.
Luis Villazon
Luis has a BSc in computing and an MSc in zoology from Oxford. His works include How Cows Reach The Ground.
Gareth Mitchell
Gareth is a presenter of Click on the BBC World Service.
KNOW SPOT
corbis, thinkstock X2, dreamstime
The largest swamp is in southwest Brazil. Called the Pantanal, it covers 15,000km2, a greater surface area than England.
Ask the Experts? Email our panel at
[email protected] We’re sorry, but we cannot reply to questions individually.
10
April 2013
VITAL S TATS
11Km (6.8 miles)
below se a Trench in level is The Maria the na deepest n Pacific Ocean is th atural poi nt on Eart e h
The booming city of Dubai is one of the most power-hungry on the planet
Polar jet stream
Is it faster to fly east or west? It’s faster to fly east because of the jet streams. These are high-altitude air currents that circle the globe at 160 to 480km/h (100 to 300mph). Each hemisphere has a polar jet and a subtropical jet, and all of them circulate eastwards. The jets are only a couple of miles wide and don’t take the shortest route across the ocean, but it’s still worthwhile for commercial flights to fly within them when flying west to east. When flying westwards they take a more direct route that avoids flying against the jet stream. The difference can be two hours’ flight time on a transatlantic flight. Spacecraft are also launched into an
QuicKFIRE Subtropical jet stream
Each hemisphere has a polar and subtropical jet stream eastwards orbit, but for a different reason. Orbital speed is relative to the centre of the Earth, rather than the speed over the ground. By launching to the east, they can add the rotational speed of the Earth to their own orbital speed. LV
What would happen if all the coral reefs disappeared? Our planet would be a different place. In the 1950s, when research began, many coral reefs were thriving but since then about 20 per cent have been lost through increasing sea temperatures and acidification. Reefs are built by tiny organisms called corals and are home to about a quarter of all marine species, even though they cover only 0.1 per cent of the oceans. If they all disappeared tomorrow, an entire ecosystem would be lost, drastically reducing our planet’s biodiversity. For
humans, coral reefs provide abundant fishing resources, as well as protection for some low-lying islands and lucrative tourist destinations. About 850 million people live within 100km of a reef, of whom about a third depend on it for their food or livelihood. If the sea temperature and acidity were favourable the day after tomorrow, then the reefs would quickly begin to grow back, but if climate change continues they might never do so. SB
How do bulletproof vests work? Bulletproof vests are designed to disperse the round’s energy and deform the slug to minimise blunt force trauma. Hard body armour is made of strengthened steel plates. It is strong and effective but also heavy and cumbersome. But some ammunition can even penetrate steel, requiring stronger materials still. The latest vests employ overlapping super-strength but lightweight composites of ceramic and titanium. Soft body armour is not as strong, but it is more lightweight and less conspicuous to wear. It is woven out of interlacing strands of Kevlar. Like hard body armour, layers of this tough, net-like material deform the incoming bullet, robbing it of its energy. GM
Is green tea better for you? All tea contains antioxidant compounds called catechins. Black involves oxidising the leaves more so than green, and so black tea is slightly less antioxidant. Studies have shown health benefits for both kinds of tea, including reduced blood cholesterol and lower rates of cardiovascular disease, but green tea seems to have the edge. This may be partly because it’s drunk without milk. Black tea with milk has no cardiovascular benefit, according to a 2006 study at Berlin University. In addition, a 2012 study in China found that green tea also repairs age-related damage to brain cells. LV
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What is the fastest-spinning star ever found? Flash drives, thumb drives, pen drives… whatever they’re called they store a lot of data
Have any planets other than Earth showed signs of global warming? ‘Global warming’ is a term applied to the rise in the mean temperature of the Earth’s atmosphere over the last century or so. The term is only ever applied to Earth because it specifically refers to the perceived effect of human activities such as burning fossil fuels. However, other planets do show evidence of the ‘greenhouse effect’, of which global warming is an example. The greenhouse effect refers to the increase in a planet’s atmospheric temperature due to the presence of
gases such as carbon dioxide, water vapour, methane and ozone. The planet Mars and one of Saturn’s moons, Titan, both have small greenhouse effects, but by far the largest greenhouse effect in the Solar System is that of Venus. The Venusian atmosphere is 50 times as dense as Earth’s and consists almost entirely of carbon dioxide, a very effective greenhouse gas. This means Venus’s mean surface temperature is over 450°C, hot enough to melt lead. AG
science photo library X2, alamy, nasa x2
Am artist’s impression of the superfast-spinning star VFTS 102 A hot blue star, 25 times the mass of the Sun, is the fastestspinning star known. Called VFTS 102, it resides within the Tarantula Nebula. At its surface, the star rotates at about 600km/s (more than 1 million mph) – so fast that it is almost, but not quite, flinging itself apart. The origins of this fast rotation are not yet clear, but it’s likely that VFTS 102 was once part of a binary star system and was ‘spun up’ due to the transfer of mass from its now dead companion. Although VFTS 102 is the fastest rotating ‘normal’ star, pulsars actually spin more quickly. Pulsars are the collapsed cores of stars that became supernovae. The fastest spinning pulsar yet discovered is known as Ter5ad. It rotates 716 times every second, which means the rotation speed at its equator is 70,000km/s – that’s about 158 million mph, or roughly 24 per cent of the speed of light. AG
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The super-hot slopes of the volcano Maat Mons on Venus is revealed in radar data taken by NASA’s Magellan probe
STATS L A IT V
What health risks have been linked to Wi-Fi? Wi-Fi is based on radio waves whose frequency is similar to that of microwaves. And given what microwave ovens can do to, say, chicken nuggets, it’s perhaps not surprising that there’s been concern that exposure to Wi-Fi could be unhealthy. Fortunately, however, while they’re pretty ubiquitous, Wi-Fi waves are emitted at far lower intensities than microwaves in ovens. As a result, they can’t produce anything like the same
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heating effect. Even so, some people still worry that perhaps even this far weaker effect could cause damage after years of exposure. To date, epidemiologists have failed to uncover any consistent evidence for even long-term effects. It does, however, suggest that the health effects, if there are any, are pretty weak, and that we should worry about more hazardous things – like tripping over all the cables we’d need if we didn’t use Wi-Fi devices. LV
Why is the Universe made up of galaxies and not just random stars? This is a consequence of the fine-scale structure of matter and energy in the very early Universe. Although the formation of structure in the Universe is not fully understood at present, astronomers believe that minute fluctuations in the density of material in the primordial Universe became the
seeds for the formation of protogalaxies and clusters. Stars eventually formed from collapsing clouds within those proto-galaxies. So it is likely that galaxies exist (rather than a random distribution of stars) simply because those primordial fluctuations were of the right scale to create them. AG
Why has the rhesus negative problem in pregnancy not been eliminated by natural selection? This problem occurs when the blood types of a mother and her foetus are incompatible, for example, when the mother is RhD negative and the foetus RhD positive. Unless treatment is given, the foetus suffers from a haemolytic disease of the new-born (haemolytic means destruction of the blood) called erythroblastosis fetalis, in which its red blood cells fail. The proportion of RhD negative genes varies between populations: it is rare in East
Asians, South Americans and Africans, but more common in Caucasians. So the question is why this gene has survived at all. The answer may be that it partially protects people against a parasitic disease called toxoplasmosis that is carried by cats and is latent in as much as one-third of the human population. If this is correct it would explain the variations around the world, since different countries have widely different levels of contact with cats. SB The number of people with RhD negative blood, which can cause problems in pregnancy, is higher in Caucasians
Galaxies are due to fluctuations in the density of the primordial Universe
How do chicks breathe when in the egg? Although a bird embryo has no functioning lungs, the eggshell isn’t airtight, so gases can still diffuse in and out. A special membrane called the allantois forms as a sausage-shaped offshoot of the developing gut. It’s covered with a fine web of blood vessels that increase the surface area in order for oxygen to diffuse into the blood and CO2 to diffuse out. The allantois is one of the adaptations that allowed animals to move from the ocean to the land. Fish and amphibian eggs don’t have an allantois, but bird and reptile eggs do. In mammals, the allantois develops even further, to form the umbilical cord. LV
Chick embryo Amnion
Allantois
Yolk sac
Yolk
Vitelline membrane
The egg allows oxygen to enter and be absorbed by the allantois and into the embryo
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Flying in a ‘V’ formation helps birds save energy during long flights
VITAL S TATS
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Why do we have fingerprints?
getty, alamy, thinkstock, John Brown/johnbrownimages.co.uk, science photo library, nasa
Fingerprints develop between the second and sixth months of pregnancy. The middle layer of the skin on the pads of the fingers begins to grow faster than the inner and outer layers, and this causes the skin to buckle into ridges. The exact pattern of those ridges is determined by the composition of the amniotic fluid and by the way that the foetus touches things as it moves around. Fingerprints have long been thought to improve grip, but a 2009 study at the University of Manchester found that fingerprints actually reduce grip slightly on smooth surfaces. They might still provide increased grip on rough surfaces, but we don’t have prints on the palms of our hands, so it’s unlikely that this is their primary function. Rather, they improve our touch sensitivity by amplifying tiny vibrations as our fingers brush against a surface. LV
Why do birds never crash into each other when flying in groups? Many large birds, such as geese and pelicans, fly in a V-formation, or echelon, both to improve flight efficiency and to avoid collisions. Drag is reduced by as much as 65 percent, and range can be increased by over 70 per cent because each bird flies in the upwash from the wing tip vortex of the one in front and uses its updraft. Only the leading bird fails to benefit, but the other birds in the flock shift around in the group to share the burden. In fact echelons are rarely perfect Vs and more often are J shapes.
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In either shape, each bird gets the best possible view of the bird in front so that it can maintain a safe distance and so avoid colliding. Smaller birds gain less advantage from flying in these shapes and fly in looser groups. When we watch them it seems miraculous that they don’t collide, but their visual system works much faster than ours, just as their metabolism and muscles do. Speeded-up films of people walking in crowded streets can appear just as miraculous. SB
Why were people shorter in the past?
Is it better to get to sleep earlier? Yes. Your brain moves through different sleep states during the night. Rapid eye movement (REM) sleep is the shallowest, and then there are three progressively deeper non-REM sleep stages. You will normally cycle from REM to deeper sleep four or five times in a night, but the deepest sleep stage lasts much longer in the early part of the night. This is controlled by your personal daily cycle of the hormone melatonin, not the time that you go to bed. After about 3am, the brain skips the deepest sleep stage altogether. And lying in late only gives you more REM sleep, which is less restful. LV
Do ants have feelings? Ants don’t have complex emotions such as love, anger, or empathy, but they do approach things they find pleasant and avoid the unpleasant. They can smell with their antennae, and so follow trails, find food and recognise their own colony. Their exoskeleton has sensory hairs on the outside but they probably cannot feel damage on the inside, which is why parasites can destroy them if they can get in without touching the sensors. Each ant’s brain is simple, containing about 250,000 neurones, compared with a human’s billions. Yet a colony of ants has a collective brain as large as many mammals’. Some have speculated that a whole colony could have feelings. SB
In the short term, because they were malnourished. For example, in the mid 19th century the average height of troops was around 5ft 5 inches (1.65m) in most European countries, 5ft 6 inches (1.68m) in England and over 5ft 7 inches (1.70m) in the USA. Men in all these countries are now much taller. Dutchmen were renowned for being short, but now average 6ft (1.83m). Even now, people in impoverished countries, such as Vietnam and North Korea, are far smaller than in other nations. Yet when they migrate to richer countries their children grow taller, suggesting the difference is not genetic. Over longer timespans, the opposite has happened. Fossils from Africa, Asia and Europe show that our ancestors were taller and more muscular than modern people from about 10,000 to 100,000 years ago. After that, skeletons became smaller, probably because of agriculture which, contrary to what you might expect, drastically reduced people’s health. Farming meant an increased population living on a far more restricted diet than hunter-gatherers. SB
Malnutrition in the 19th century meant people were smaller
Could a tree grow in zero-g? Normal plant growth relies on gravity to provide a direction indicator. Tiny starch particles settle at the bottom of cells called statocytes to signal the plant to produce more of the hormone auxin at that end. This is what tells roots to grow downward and shoots to grow upward. Without gravity, the shoots just grow towards water, instead of breaking free A zucchini plant grows on the into the air, and they quickly go mouldy. With careful International teasing though, they can be encouraged to grow in the Space Station in a special bag right shape. Because of the very limited space available on the International Space Station, nothing larger than a pea plant has been grown in space yet. Five species of tree have been grown on Earth, from seeds that flew around the Moon on Apollo 14, but we still don’t know exactly what effect prolonged zero-g conditions would have on tree growth. LV April 2013
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Snapshot
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History
Cold light of day The morning after the night before pedestrians walk amongst the carnage and mayhem left on Beijing’s Chang’an Avenue, off Tiananmen Square, following the People’s Liberation Army’s (PLA) brutal crackdown on student demonstrators in the capital. Following the death of former General Secretary Hu Yaobang on 15 April, mourners gathered in the square to mark his passing. A controversial leader, Hu had been forced to resign as head of the Communist Party due to his increasingly pro-democratic political leanings. Around 100,000 protesters marched on the square the day before his funeral and remained there for many weeks. Late at night on 3 June, PLA soldiers and tanks moved in to clear the protesters – with great loss of life. The initial Chinese Red Cross report of 2600 deaths was retracted following pressure from the government, who in turn claimed only 241 lives were lost. Twenty years on, the exact figure, believed by many to be in the thousands, remains unknown.
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xxx David Turnley/CORBIS
Beijing, People’s republic of china, june 1989
Science
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Odd ball
xxx Los Angeles Department of Water and Power
Los Angeles, CA This may look like a strange case of pollution, but these plastic ‘shade balls’ have been released into the Ivanhoe Reservoir in California deliberately. They act as a sunscreen covering the water’s surface to limit the amount of sunlight that gets through. Too much sunlight is a problem as it increases the chances of a chemical reaction in which bromate – a potentially carcinogenic substance – is formed. Bromate is created when the naturallyoccurring bromide in the water combines with the chlorine that is added to kill off bacteria. This problem has led to some pretty drastic action. After abnormally high levels were detected in December 2007, the Los Angeles Department of Water and Power had to drain the reservoir, which, together with Silver Lake reservoir, supplies some 600,000 people in LA. About three million shade balls were added to the reservoir last year and they will stay there for around five years until a new underground reservoir facility is built. 18
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Snapshot
Nature
By the teeth of their skin It looks like a sculpture by HR Giger. But this is actually shark skin, magnified 70 times by a scanning electron microscope. The skin of a shark is rough to the touch, like sandpaper, and the jagged structure revealed in the image explains why. The sharply pointed scales are known as dermal denticles, and are remarkably similar in structure to teeth. Each is made of dentine – the chalky substance that makes up the interior of a tooth – and is covered with dental enamel. The lower portion is made of bone, which anchors the denticle to the skin below. The denticles mesh together to form a tough exoskeleton that surrounds the shark, and to which some of its swimming muscles are attached. Their streamlined shape diffuses water turbulence and improves hydrodynamic flow around the shark, helping it slip through the water more quickly and efficiently. Knowing this, engineers have attempted to mimic the microstructure of shark skin in the design of boat hulls and the outer skin of aircraft. Swimwear manufacturer Speedo has even copied shark skin in the design of its ‘Fastskin FSII’ competition swimsuit.
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Spiny dogfish shark
Update
The latest intelligence
E Are satellites going to replace trowels and maps when it comes to discovering ancient cities? p24 E Is working out affecting your genes? p25 E Are computers better handled to detect liars? p25
The Tevatron particle accelerator in Illinois, USA
Neutrinos don’t break the speed limit… …but they could revolutionise communication hysicists at the ICARUS experiment in Italy measured the time it took for seven neutrinos to reach a liquid argon-filled detector after they were released from the CERN particle physics lab in Switzerland, 730km (450 miles) away. They found that neutrinos travel at roughly the speed of light, but no faster. The ICARUS experiment is located in the same lab within the Gran Sasso mountain in central Italy as the OPERA experiment that produced the results which flew in the face of Einstein’s special theory of relativity. The final nail in the coffin for faster-than-light, or
science photo library
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superluminal, neutrinos may well come in May, when all four of the experiments in Gran Sasso – OPERA, ICARUS, Borexino and LDV – will time beams of the particles released from CERN. Neutrinos have been used to send a message for the first time. Although it’s still
Physicists sent a simple message through 240 metres of stone. These humble first steps show that a completely new means of communication is feasible that would enable links which are not currently possible. To test the system, physicists in the US converted the word ‘neutrino’ into binary
Neutrinos have been used to send a message for the first time. early days, the ability of these subatomic particles to travel vast distances through almost any material makes them an exciting alternative to radio waves, which are easily blocked by mountains and oceans.
code, a series of 1’s and 0’s. A beam of neutrinos from the Tevatron particle accelerator at the Fermi National Accelerator Lab near Chicago was then modulated, with a pulse of neutrinos corresponding to a ‘1’
and no neutrinos corresponding to a ‘0’. The resulting signal was received at the MINERvA neutrino detector in a cavern 100 metres underground, where it was translated back into letters. Neutrinos (‘little neutral ones’ in Italian), have zero electric charge and an almost non-existent mass, so they rarely interact with matter: they can pass right through Earth. They could provide a means to communicate with nuclear submarines, since radio waves don’t travel well through salt water. They could also be used to send messages to a rover or base on the far side of another planet. “In cases where large amounts of matter would need to be penetrated to allow communication, neutrinos could save the day,” says Professor Kevin McFarland, a physicist at the University of Rochester, which led the research. But the ‘neutrinophone’ technology still needs more work to be of practical use. The very property that makes neutrinos such an exciting prospect in communications, their ability to penetrate matter, also makes them extremely difficult to detect. The MINERvA detector weighs 170 tonnes, not a practical possibility aboard a sub. “The neutrino beams we currently make are not sufficiently intense to send a lengthy message and are difficult to point at a moving target,” says McFarland. “But increasing the beam intensity is one of the main areas that’s being investigated right now.”
Update
The latest intelligence
Desktop dig
Jason Ur/Bjoern Menze x2, science photo library, corbis, University of Sheffield, dr brian choo
The map (inset) reveals the likelihood of ancient settlements in Tell Brak, Syria
Archaeologists are increasingly able to make discoveries without getting their hands dirty, by scouring satellite images. Some techniques, like the one developed by Ur and Menze, are highly sophisticated. But Google Earth is enabling archaeology to be carried out using a desktop computer. In 2011 it was announced that almost 2000 potential archaeological sites had been found in Saudi Arabia using the virtual world map. “Every six months I read about someone else who has used Google Earth to find an archaeological site,” says Ur. “It’s a good thing, because as cities are growing and agriculture is intensified, it has a destructive effect on global cultural heritage. Methods like this have the ability to quickly document what’s there.”
Automated archaeology Satellite identifies thousands of ancient settlements in just one day wapping trowels and maps for satellites and algorithms is enabling archaeologists to search thousands of square kilometres of land for lost towns and villages overnight. The technique relies on the fact that the mud bricks used to build homes in many locations leave their mark on the landscape in the form of ‘anthrosols’, which have a lighter appearance than natural soil. Several images of the same patch of land taken by the ASTER satellite, each focused on a different part of the electromagnetic spectrum, are used to pick out different characteristics of the anthrosols.
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When data from these different wavelengths is combined using an algorithm, it provides an accurate prediction of whether an archaeological site lies beneath. In early tests using the method on a 23,000 square
“In the past, we archaeologists worked on the ground and either studied small areas intensively, or large areas with low intensity. We looked out the window of a Jeep to spot sites, and would only find the biggest settlements,”
using this method... in northern Syria, 14,000 settlements were discovered kilometre (14,300 square miles) area in northern Syria, 14,000 settlements were discovered. Buried in sand and soil over time, the villages date from the late Neolithic right up to the recent past.
says Dr Jason Ur, the Harvard archaeologist behind the technique. “This new method combines the intensity of the small search with the wide coverage of a broad one.” In this way, the outlines of
towns and villages can be traced out. “The algorithm runs on powerful computers overnight,” says Ur, who developed the technique with MIT computer scientist Bjoern Menze. When the outlines of settlements are combined with an elevation map, an estimate of each village’s volume is generated. This gives an indication of its longevity, as villages would expand outward and upward as they grew. “I’m now planning a research project for Iraq’s Kurdistan region,” Ur says, “but the algorithm should work well in similar environments elsewhere, such as the Niger Valley and coastal South America.”
EEE ROUND UP Keeping abreast of the top science, history and nature research from around the world
ENVIRONMENT Coral resists global warming It’s become a symbol of global warming: corals turning white and dying off as sea temperatures rise. But a team of marine biologists that includes British scientists has found evidence that corals may adapt to warmer waters. Colonies of the Acropora coral in Singapore and Malaysia that had bleached in 1998 were healthy after the waters warmed again in 2010. It’s not clear whether it’s the coral itself that adapts, or the algae zooxanthellae, which is expelled from the coral when it bleaches.
computing
Columbo step aside – humble computers are more effective at detecting liars than experienced interrogators. In tests at the University of Buffalo in the US an automated system that analysed the eye movements of volunteer interviewees in video recordings correctly identified when someone was lying or telling the truth 82 per cent of the time. Interrogators typically have a 65 per cent success rate. The system focused on the rate of blinking and the frequency people shifted their gaze.
Corals are losing their vibrant colours as sea temperatures rise
genetics
A good workout not only makes your muscles stronger, it also affects your genes. Physiologists at the Karolinska Institute in Stockholm took biopsies from the muscles of volunteers who had been riding exercise bikes. They found that genes involved with energy production had been altered. The coating, or methylation, around promoter regions – sections of DNA that control the activity of specific genes – had been removed. The change is thought to boost the work capacity of muscle.
NEUROSCIENCE
At times of anxiety and depression, we tend to make negative decisions – choosing options that present fewer problems but less rewards. Now neuroscientists at MIT in the US have found the source of these negative thoughts. They offered monkeys a choice between large rewards that came with an annoying air puff and small rewards without one. They were more likely to avoid the puff and take a smaller treat when the anterior cingulate cortex was stimulated, showing that area of the brain was responsible.
geology
The abandoned factories and homes in Detroit have turned the US city into a natural lab. Geologist Dr Jeffrey Howard at Wayne State University is using vacant land to study soil formation particularly the weathering of rocky and mineral objects. Knowing when a building was demolished provides an accurate date at which soil started to develop something that’s impossible to know in nature. The research is already showing similarities between the weathering of chunks of mortar and iron nails, and that seen in natural rocks and minerals. April 2013
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Comment & Analysis
Bill McGuire considers whether we should be toying with what lies beneath
“Drilling into a supervolcano is a bit like sticking a drawing pin into an elephant’s bottom”
The signs at the Campi Flegrei supervolcano helpfully warn of “burning danger”
uring prehistoric times, cataclysmic eruptions at one or other of the world’s supervolcanoes devastated huge tracts of our planet and, on one occasion, may even have brought the human race to the brink of extinction. It is more than 25,000 years since the last titanic explosion at a supervolcano – in Taupo, New Zealand – so modern society has never had to face the trauma of a volcanic cataclysm with the potential to trigger a global freeze and worldwide harvest failure. But the threat remains ever-present. You might think, therefore, that drilling into one of these monstrous volcanoes is probably not a good idea. This, however, is exactly what a European consortium of scientists is about to do in southern Italy. Opposition from many citizens and local politicians, who fear that the drilling may trigger an eruption,
Alamy, Nasa / bill white, Science photo library
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has resulted in repeated delays to the project. Now, though, scientists appear to have allayed these fears as much as they can, so all is set for a borehole to slice 3.8km (2.4miles) down into the Campi Flegrei supervolcano near Naples later this summer.
It is more than 25,000 years since the last titanic explosion Past activity Campi Flegrei is not the volcano that everyone associates with the city of Naples. Whenever the ground has rumbled in the past, the eyes of its residents have inevitably turned eastwards towards the brooding double peak of Vesuvius, rather than to the west, where Campi Flegrei sits. This all changed
in the late 1960s and early 1970s, when swarms of earthquakes and the bulging upwards of the crust resulted in the giant volcanic crater joining the ranks of the so-called ‘restless’ calderas, others of which include Yellowstone in Wyoming and the Greek island volcano, Santorini. There is still plenty that we don’t know about supervolcanoes. Volcanologists have speculated that the reason magma is often released in one massive burp rather than in dribs and drabs is because the crust above swells and stretches, opening up fractures that slice down from the surface, instantaneously creating a conduit. Given such a scenario, it remains uncertain, however, what warning signs – if any – might be seen before a super-eruption, or how soon in advance they would become apparent. We also can’t determine whether an episode of unrest will die down again or
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culminate in a volcanic blast of unimaginable proportions. Ready to rumble One such unsettled period provided a frisson of excitement for the population of the northwest US, when swelling of the Yellowstone supervolcano, which started in 2004, was accompanied in 2009 and 2010 by thousands of small earthquakes, suggesting that magma was on the move. To everyone’s relief, unrest at Yellowstone has subsided – at least for the moment. However, one day, somewhere – maybe at Yellowstone itself, at Toba in Sumatra, or at Bolivia’s remorselessly swelling volcano, Uturuncu – such rumblings will translate into an eruption. So we need to learn now how to recognise the tell-tale signs that will give us sufficient warning. It is hoped that the drilling campaign at Campi Flegrei will help to do this by allowing researchers to build a detailed picture of a supervolcano’s innards. Sensors lowered down the borehole will provide measurements on the mechanical properties of the volcanic rock, including permeability and temperature, as
well as monitoring future changes in those properties that might herald an eruption. Extracted samples will also enable the hidden products of past eruptions to be catalogued. Although Campi Flegrei’s last eruption, in 1538, was pretty small, its greatest prehistoric
There’s a very good chance that Campi Flegrei will host another cataclysmic eruption blasts were titanic. Today, such an event could threaten the lives and livelihoods of several million people.
The vivid natural colours of a ‘restless’ caldera in Yellowstone in Wyoming, US
History repeating? With this in mind then, should volcanologists be taking the risk of poking this sleeping giant? Could their interference actually provoke an eruption? There is precedent for magma coming up a borehole. In Iceland in 1979, magma moving deep underground encountered a kilometredeep borehole drilled to tap geothermal energy. Around three tonnes of fluid basalt spluttered out of the top of the hole before the magma congealed and blocked the conduit. The magma lurking below Campi Flegrei, though, is much stickier and deeper down, so the chances of any managing to squeeze up a thin tube nearly 4km (2.5miles) long to reach the surface are vanishingly small. In short, drilling into a supervolcano is a bit like sticking a drawing pin into an elephant’s bottom and can be expected to have a similar effect – none at all. There’s a very good chance that Campi Flegrei will host another cataclysmic eruption, but not this year. Bill McGuire is the author of Waking the Giant: how a changing climate triggers earthquakes, tsunamis and volcanoes (OUP, 2012)
What do you think? Is drilling into a live volcano an act of idiocy or inspiration? Email:
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130 million years ago is when the first known case of osteoarthritis occurred – in a peacocksized dinosaur bird called Caudipteryx. The characteristic degeneration of bone and cartilage joints was spotted in fossils in Chinese museums.
1 million years ago is when one of humankind’s ancestors, possibly Homo erectus, is now known to have been using fire. The revelation came after the discovery of ash at the Wonderwerk Cave in South Africa. The earliest known use had been less than 400,000 years.
3862 km (2400) miles is how far some golden-crowned sparrows are now known to migrate from California to breeding sites in Alaska. Before the birds were tagged, it had been a mystery where they disappeared to each year.
40 per cent more brainteasers were solved by volunteers who had drunk the equivalent of two pints of beer compared with those who had not. It is thought that a little tipple aided creative problem-solving in the study conducted by the University of Illinois.
5.56 kilojoules per square metre is the amount of energy required to rip apart cuticle taken from the hind legs of locusts. This means the insect’s skeletons require more energy to tear than cast iron.
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World in context India Celebrated author, and social commentator Gurcharan Das, in conversation with Moshita Prajapati, highlights the need for reforms, acknowledgement of India’s growing middle class and a strong liberal state ow would you define India’s current economic and business climate ? The realisation has come to us in India that our soft underbelly is poor governance. The economy is going to keep growing - we are in a slow down presently, but I think we will go back to 7-8 per cent growth rate sooner rather than later. Although our reforms are painfully slow but even slow reforms add up. And I think we will go back to being the second fastest growing economy (or may even become the fastest because of our younger demographic. Japan, Europe (and even China) have an ageing society, where the working people (who support the very young and the old) are diminishing. And so growth has slowed down (or will slow down in the case of China).
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What do you hope from India’s young demographic? What we saw with the Anna Hazare movement is the impatience of India’s youth with governance. Since it is not politically represented, it is using the method of protest which is backed by media. But this will only take them 28
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so far. Ultimately, you need to engage in politics. Not only do you have to vote, but also acquire other democratic “habits of the heart”. I also suggest that one devote one hour of service per week for your neighbourhood. In other words, not worry about the corruption of Robert Vadra, but worry about the corruption in your neighbourhood. Engage in your neighbourhood politics, making sure that the garbage is collected, lights are working on the streets, roads are in a good condition, etc. Why do you see the common man as the purveyor of change in Indian society? The new aam admi (common man) emerging in India is a young middle class person. The middle
class in India is entirely the creation of the 1991 type of reforms. The middle class in India was 2 per cent in 1950, which jumped to 8 per cent in 1980 and today it is 25-30 per cent of the population. The future of India will be written not by the aam admi of the Congress who they believe is a starving peasant, toiling in the sun. It will be written by that young middle class who live in the cities. These folk might not own cars, but have scooters or motorcycles. The middle class is already between a quarter and a third of India, depending on how you define the middle class. This will rise and will be half of India. Then politics will have to change to accommodate this. The irony is that none of the politicians are addressing this new middle class. And this middle class is behind the Anna Hazare movement and the movement against violence
in areas still controlled by the state. For instance, telecom is liberalised but government still controls the spectrum. If they had been clear rules from the beginning of how to allocate spectrum, then there would have been no corruption or the 2G scam. So, corruption is related to the lack of reforms. Do you think redefining the role of the government would help in accountability of its services? The job of the government is governance. We have burdened the government with too many jobs. Anything happens and we ask for a new law. So, you end up with too many laws without increasing the capacity of the state to implement them. Does the aam admi hold the key to India’s economic growth?
against women. It is this class that is going to make history. This is the aam admi of our future. What is the relationship between growth and reforms? I think growth is happening because of the reforms. Corruption is present in the unreformed sectors. Once you reform a sector, corruption declines. For instance, real estate and mining are two sectors that are not reformed in the country. Here, the rules are not clear. In the pre-reform days, there was far more bribery - for example you needed to bribe someone to obtain a telephone, to get a ticket for Indian Airlines or in the railways. Now you don’t have that kind of corruption. What you do have is corruption
What is a liberal state? It should not take 12 years to build a road or 15 years to get justice in the court. To achieve that we must reform the bureaucracy, the police and the judiciary. That reform will do more to cut out corruption than anything else. To achieve this we need to reaffirm the strong liberal state which is envisioned in our Constitution. A liberal state is one where the executive has the ability to take quick decisions and decisive action. Two, that action should be bound by the rule of law. And three, it is accountable to the people. These three ideas, these three pillars of a strong liberal state, are not self-reinforcing. They actually sometimes act against the other because any excessive kind of attempt to achieve accountability
We need politics of aspiration not of grievance
makes the ability to take action weaker. For example, the Anna Hazare movement has so scared the bureaucrats; they won’t even put their signature to paper anymore. We need to give them back their ability to act but hold them accountable. A strong liberal state is not easy to achieve, but many democracies have been able to do it. Scandinavian democracies are the best in class. Do you think India is moving towards it slowly? We have achieved a lot and we mustn’t forget that. We don’t need a revolution—we need a peaceful reform of our governance institutions. If the middle class engages in politics and demands reform things will change. No political party today singlemindedly talks about the reforms of bureaucracy, police and judiciary single-mindedly. The middle class doesn’t know who to vote for today and I don’t blame them. The fact is almost all parties follow politics of grievance. They treat us like victims. Congress says, “Oh you’re a victim of globalisation and liberalisation so I have to give you subsidised diesel, free electricity and jobs.” The BJP treats you like a victim of a 1000 years of Muslim rule. The Dalit party treats you like a victim of upper caste oppression and so do the OBC parties. So nobody is really talking to the aspiring new middle class. We need politics of aspiration not of grievance. Gurcharan Das is an author and a social commentator. He is the author of two international bestsellers The Difficulty of Being Good: On the Subtle Art of Dharma and India Unbound. His latest book, India Grows at Night: A Liberal Case for a Strong State redefines the new aam admi and discusses what we have to do to save our democracy. April 2013
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Feature in here Science
Life
Life
The Origin of life p32
life on other planets p38
The meaning of life p40
Without going back a few billion years in time, it’s impossible to know for certain how life began here on Earth, but scientists have a good idea...
Are we alone in the Universe or has life evolved elsewhere too? What is being done to make contact with our intergalactic neighbours?
The purpose of life has puzzled humankind for thousands of years, and yet we’re still no closer to finding an answer to the ultimate question.
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Thnkstock x2, science photo library, paul wootton
• What is it? • Where does it come from? • And what does it mean?
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Life The origin of
Every living thing on Earth evolved from a single ancestor. But where did it come from, and how did it form? JV Chamary looks back in time
ow did life begin? The biggest question in biology is also one of the hardest to answer – and the most controversial. Scientists debate every step in the path to the first living organisms – and revealing the molecules and mechanisms that drive life will almost guarantee a Nobel Prize. Part of the problem with studying the genesis of biology is that it leads to another tough question: what is ‘life’? And there are over a dozen definitions. NASA’s exobiology programme, for example, adopted a definition of life as “a selfsustaining chemical system capable of Darwinian evolution”. So one way to identify life’s common characteristics is to remember that living things aren’t really ‘things’ at all. Life is a process, driven by chemical reactions, or metabolism. But while we don’t have all the answers to how life originated, recent research is offering exciting new clues. Last year, scientists revealed the world’s oldest fossils, which were found in 3.4 billion-year-old
Thinkstock, Corbis, David wacey
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sandstone from Strelley Pool, Western Australia – one of the first known stretches of beach. This rock contains microscopic structures that look like cells. They’re surrounded by a chemical fingerprint of biological activity: isotopes of carbon in proportions that indicate conversion from inorganic CO2 into organic molecules produced by living cells. “We came across remarkably well-preserved things in little windows between the sand grains, which seem to have avoided all the usual crushing and cooking,” says Martin Brasier, a palaeobiologist at the University of Oxford. “These are cell-like structures. We find biological-type morphology; the chemistry is consistent with biological metabolic pathways.” The chemistry of the rock also suggests that these primitive microbes generated energy through chemical reactions that use sulphur, similar to sulphur bacteria found today. This means that these ancient microbes were a relatively sophisticated form of life and
unlikely to represent the very first living organisms. First organisms So when did life begin? It’s unlikely that the first organisms appeared earlier than four billion years ago, 500 million years after Earth’s formation. Back then, our planet was a watery world with land in the form of arcs of islands, but no true continents. Our Sun was only 70 per cent as bright as it is today, with volcanic activity bringing temperatures up to clement conditions of around 25-60ºC (77-140ºF). The Moon was closer than it is today, generating stronger tides, and the Earth was spinning faster, meaning shorter days lasting eight to 10 hours. The surface was also regularly pummelled by rocky debris left over from the early Solar System during an event known as the Late Heavy Bombardment, when meteorites 10 times larger than the one that killed the dinosaurs were not uncommon.
Origin of life
SCIENCE
The 3.4-billion-year-old fossilised remains of cells found in Strelley Pool, Australia
Stanley Miller, along with Harold Urey, attempted to recreate the ‘primordial soup’
Ending 3.8 billion years ago, this Hadean eon – named after the Ancient Greek underworld – sounds like hell on Earth, but it was heaven for the first microbes. Meteorites would have delivered important metals and some of life’s building blocks to the surface, for instance, while volcanic power and sunlight provided free energy. So, although early Earth would seem hostile to us, it would have been a lively place in terms of generating life. Cloaked by greenhouse gases, the atmosphere had no oxygen – a waste product of photosynthesis generated by plants and algae, which didn’t exist at that time. Instead, the early atmosphere would have contained methane, carbon dioxide, sulphur dioxide, hydrogen sulphide and plenty of water vapour. “All these things sound toxic to us, but most are perfect fuels for microbial life,” says Brasier. “It was a microbial paradise.” We may never discover physical remains of early life preserved in the fossil record further back in time than the Australian micro-fossils. “Beyond 3.5 billion years ago, the evidence is wholly mineral or chemical, perhaps because these older rocks are too
cooked to preserve the remains of cells,” Brasier explains. “All of life is cellular – that is why fossilised cells provide a fundamental benchmark for the beginnings of life.” So, in order to reconstruct the events that came before the first cells, some scientists are taking a different approach: they’re simulating how life might have once evolved by creating its ingredients in the laboratory. This approach was inspired by
Living things aren’t really ‘things’ at all. Life is a process an idea from the 1920s, which proposed that the first organisms emerged from a ‘primordial soup’ of organic molecules. A seminal test of this soup theory was carried out in 1952 by chemists Stanley Miller and Harold Urey. Using a sealed glass apparatus, they passed an electric spark (to simulate lightning) through a mixture of gases thought to have been present in Earth’s primitive atmosphere:
methane, ammonia, hydrogen and steam. The water that condensed in the artificial ‘ocean’ contained amino acids – the building blocks of proteins necessary for life. Scientists who study the chemistry that preceded the first cells emphasise that life didn’t appear in a single event. “The origin of life is not a Big Bang,” says Philipp Holliger of the MRC Laboratory of Molecular Biology in Cambridge. “There isn’t a divine spark where things come alive – it’s more a transition. There would have been a grey zone where things became more and more lifelike.” Key ingredients So if cooking up the precursors to life in a primordial soup needs a slow simmer, what are the ingredients? All living things are made up of DNA, RNA, proteins and lipids – four molecules that each play a crucial role in cells. Lipids, for instance, make up the membrane – the barrier that separates a cell from the external environment, enabling it to regulate its internal metabolic reactions. But while life’s recipe always includes these four ingredients, this may not always have been the case. The paradox is this: in modern cells, proteins provide structural support and act as enzymes – catalysts that enable chemical reactions – while the genes in DNA encode the information for producing the proteins. So it’s a classic chicken-or-egg conundrum: which came first, DNA or proteins? The answer, it seems, is neither. They were preceded by DNA’s big brother: RNA. Although they’re both formed from nucleotides – the four E April 2013
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Science
origin of life
E ‘letters’ that make up DNA and RNA sequences – the two molecules have different personalities. While RNA is a reactive molecule consisting of a single strand of nucleotides, DNA’s characteristic double-helix structure makes it chemically stable, and therefore a more reliable molecule to use as a store for genetic information. Like proteins, RNA strands can also fold into three-dimensional structures that bring molecules together to help catalyse reactions. In principle then, RNA could perform the functions of DNA and proteins, acting both as information carrier and catalyst. If the reactions included the ability to string together nucleotides to create a copy of itself, the molecule would have possessed life’s defining properties: the ability to replicate and inherit information. In other words, to reproduce.
An RNA world Most biologists believe that RNA could have been the ‘first replicator’ and that the primordial Earth was once an ‘RNA world’, dominated by these precursors to life. The best evidence to support this comes from ribosomes, the cell’s protein-making factories. Most of the reactions in cells are catalysed by proteins acting as enzymes, but the enzyme at the heart of the ribosome is actually a
Science photo library, Janet iwasa, NSF / NOAA
Early Earth was a microbial paradise, its atmosphere loaded with greenhouse gases and abundant in energy from volcanoes
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‘ribozyme’ – an enzyme made of RNA. As the ribosome is used by all life, it’s probably an ancient remnant from the RNA world. The self-replicating molecule from the RNA world has been lost in the mists of time, however. “The best we can do is build a molecular doppelgänger in the lab and try to study its properties to help us understand what went on four billion years ago,” says Holliger. “Self-replication, together with heredity, would provide a transition
In 1871, Darwin said he hoped life began in a “warm little pond” from the world of chemistry to the world of biology.” So far, Holliger has created a 200-letter-long RNA enzyme that can read and write short stretches of RNA, including its own sequence of nucleotides. The aim is to get this RNA enzyme to copy its entire sequence. Mistakes in the copying process, known as mutations, could actually cause an RNA to become better (faster or more accurate) at replication. And with a limited supply
of resources in the environment, in the form of the nucleotide building blocks, you would effectively end up with a form of evolution by natural selection. It would be ‘chemical selection’ driven by survival of the most efficient catalysts. The next step in reconstructing life is to create a cell. Membranes are made of lipids – molecules with a water-loving head and a fat-loving tail. These form a double layer (bilayer) of lipids in which the fatloving parts of the molecules face each other to form the oily filling in a water-loving sandwich. Like oil droplets in water, the chemical groups that prefer water or fat clump together, spontaneously selfassembling to form a ‘vesicle’, a sphere with water on the outside and inside. And if the contents of this lipid bubble contains RNA, you’ve effectively created a primitive cell, or ‘proto-cell’. A swell time Studying the behaviour of RNA enclosed within these proto-cells has led to some interesting insights into the precursors to life. While working with proto-cell pioneer Jack Szostak, biophysicist Irene Chen of Harvard University discovered that proto-cells swell as RNA replicates. Membranes are ‘leaky’ when it comes to small molecules such as nucleotides. But once they’re inside, nucleotides are strung together into long RNA strands that are too big to leave. And because RNA molecules are negatively charged, small positively charged ions are dragged into the cell through electrostatic attraction. Water then follows the ions through osmosis, causing the proto-cell to swell. “We found that the RNA could translate its growth directly into the growth of the cell as a whole,” Chen explains. “It doesn’t require enzymes or anything else to be added to the system. It’s just a consequence of the physical and chemical properties.” Cells that exploit the available resources to grow faster would then be able to out-compete others – the beginnings of natural selection. But some scientists doubt that
origin of life
reproducing life in the lab will ever tell the story of how it all began. “Even if we made an experiment today where we put chemicals on one side and got newly synthesised life out the other side, it still wouldn’t prove that we arose that way – we’d just have a narrative that would make it more plausible,” says Bill Martin, an evolutionary biologist at the University of Düsseldorf in Germany. Martin adds that the idea of life emerging in a primordial soup filled with organic molecules is outdated: “Organic soup has been around as a concept for 80 years, before anybody had a clue as to how cells actually harness energy.” The major point of contention among researchers centres on the source of the soup’s ingredients. “There’s an assumption that you simply fill the soup with whatever you want,” says biochemist Nick Lane of University College London. “The problem is that there’s no evidence there ever was a soup like that.” Whereas many ‘RNA world’ supporters think RNA arose first and evolved the ability to consume organic molecules already present in the soup, others believe that cells had to first become capable of producing organic molecules and generating energy through metabolism. For proponents of this ‘metabolism first’ origin of life, such as Lane and Martin, organisms could only evolve if the environment contained a system for generating the energy required to drive the chemical
reactions of metabolism. Today, in all cells that contain a nucleus and use oxygen, energy is generated by mitochondria. These structures, the powerhouses of the cell, generate energy through the movement of charged atoms (ions) across their membrane, creating an electrochemical gradient between the inside and outside. Imagine a hydroelectric dam. The pressure created from having more water on one side generates power as water flows through a turbine. Something similar happens in mitochondria, but with protons (hydrogen ions) replacing water. Protons flow down a gradient in concentration from high to low inside a mitochondrion. The protons pass through a molecular ‘turbine’ called ATP synthase, generating power. Meanwhile, the ATP synthase ‘turbine’ uses the energy released from the flow of protons to manufacture ATP molecules, the energy currency of the cell. ATP is used to pay for the chemical reactions needed for life; an adult human will make their own body weight in ATP every day, recycling each molecule over 1000 times. And it’s proton gradients that ‘metabolism first’ scientists believe generated the energy necessary to sustain early life. The question is, what produced these gradients before oxygen, membranes and ATP synthase? To answer how life began from energy, you also need to know where these gradients already existed.
A computer model of a proto-cell, revealing a lipid membrane surrounding DNA
A ‘white chimney’ in the Atlantic provides ideal conditions for primitive organisms
SCIENCE
Did life begin on land or at sea? In 1871, Darwin said he hoped it began in a “warm little pond” – and this remains a big debate. In February 2012, physicist Armen Mulkidjanian suggested that, based on the composition of ions in modern cells, life might have evolved near geothermal pools in Kamchatka in the Russian Far East, similar to those in Yellowstone National Park in the US. Highly controversial, critics point out that the early Earth didn’t have much land – reducing the potential space on which life could form – and that rain could wash away or dilute the contents of the pools. Other proposals include beach-sized rafts of pumice stone and underwater ‘mud volcanoes’ now exposed above sea level in Greenland. Black smokers The ocean is another option, as the depths could have protected early life from the damaging effects of UV rays. Until recently, the leading contenders were hydrothermal vents called ‘black smokers’, formed at fissures in the sea floor that release superheated water. But these are relatively short-lived, too hot for life (400ºC, or 750ºF) and too acidic. The leading candidate for the cradle of life is alkaline hydrothermal vents, like those at Lost City, a region of stone towers along a volcanic fault in the mid-Atlantic. Minerals from alkaline vents precipitate as mounds, but can grow to form intricate, white chimney-like structures. What’s special about these vents is that heated water emerges at under 100ºC (212ºF) – cool enough for E
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FROM SOUP TO CELL The complex chemistry that shows how life might have evolved at a hydrothermal vent
Acidic Ocean
Acidic Seawater Pore
Hydrothermal vent
More acidic
Alkaline fluid
Pyrophosphate molecule
Crust Water
Fluid Less acidic Iron Sulphur
1 primordial soup
Water seeps down through the Earth’s crust and reacts with minerals to produce a hot fluid, rich in hydrogen and sulphur. This alkaline fluid rises up through the sea floor (a vent) and reacts with iron in the ocean, forming ironsulphur bubbles that precipitate as a hydrothermal mound.
Two interconnected pores
H+lons
2 Metabolism
Organic molecules are synthesised from CO2 (from seawater) and hydrogen (in the vent fluid), the reactions catalysed on the iron-sulphur surface of pores in the mound. The difference in acidity between acidic seawater and alkaline vent creates a proton gradient between pores.
3 Energy Exchange
Molecules emerge that act as an ‘energy currency’. Today, all cells use ATP, but early life used a simpler molecule like pyrophosphate. These molecules capture energy from the electrochemical proton gradient and release it to synthesise complex molecules from life’s building blocks.
RNA Doublestranded RNA Singlestranded RNA
Warm
Amino Acid
Pores Cold Nucleotides
Lipid membrane
RNA Codon Nucleotides
Lipid Membrane
RNA Enzyme
4 RNA World
RNA and other molecules get concentrated in pores through hydrothermal currents. In the warmer pores, doublestranded RNA molecules separate to create two templates for making more RNA by adding nucleotides. In colder pores, RNA folds into enzymes that copy the RNA molecule itself.
DNA
Amino Acids RNA
RNA Enzyme
7 DNA and Proteins
Being more stable than RNA, DNA takes over the role of storing genetic information. Proteins prove to be better enzymes than RNA and their versatility enables them to catalyse a variety of metabolic reactions. The protein ATP synthase allows proto-cells to capture more energy.
5 Proto-cells
Membranes (made from lipids) assemble into cell-like bubbles, which enclose other molecules to form proto-cells. Self-replication of RNA forces cells to divide. Mistakes in copying RNA (mutations) create a variety of cells that compete for resources – the start of natural selection.
8 CELLS
The evolution of LUCA, the Last Universal Common Ancestor of all life on Earth. Proteins that pump ions out of the cell allow the organism to generate its own electrochemical gradient without needing the difference in acidity at the hydrothermal vent. These primitive microbes are then able to leave the vent.
6 THE Genetic Code
Amino acids bond to several RNA letters to create words (codons). The full vocabulary of different words forms the genetic code, which allows the four-letter alphabet of RNA to be translated into the language of proteins. Instructions for making proteins from amino acids is encoded in genes.
Lots of H+ Few H+
ATP Protein Enzyme RNA
DNA
ATP Synthase
origin of life
E life – and they’re thought to last 100,000 years, long enough to give life a good chance to get going. Most importantly though, the alkaline interior of hydrothermal mounds maintains a natural proton gradient that early life might have exploited to generate energy. “Think of a hydrothermal mound as an energy and materials capturing device, like a factory that puts the components together on site, rather than just sloshing around in some incredibly dilute soup,” says geochemist Michael Russell of NASA’s Jet Propulsion Laboratory in California, a leading proponent of the theory that life began at alkaline vents. The proton gradient is driven by the difference in acidity between the seawater and the inside of the vent. Inside the vent is alkaline, while the seawater in the early oceans would have been slightly acidic. A geological process in the Earth’s crust (serpentinisation) delivers a constant flow of hydrogen into the vent as proton ions. This maintains the gradient, with protons flowing toward the region of lower concentration: the acidic seawater. Hydrogen and minerals are pushed through a network of pores in the hydrothermal mound by currents, which helps concentrate molecules in the same place. It’s inside these micro-compartments that life may have begun. The mineral walls between pores act like a membrane, generating a gradient in proton concentrations between adjacent pores. “You start off with some kind of chemistry happening, but you first need compartments to contain anything that you make,”
says Russell. The mound walls don’t have the ATP synthase to capture the energy released from the flow of protons. Instead, in the early oceans, the walls would have been made from ironsulphide, creating a catalytic surface for exchanging electrons between molecules. This allowed hydrogen from the vent to react with CO2 in the water, producing organic molecules: in other words, the beginnings of metabolism. “I’m happy with the RNA world, but it’s something that comes in
The order of the steps to the first cell will always be controversial later,” says Russell. In the ‘metabolism first’ scenario, lipid bubbles would then have formed inside the pores of a hydrothermal mound and enclosed RNA molecules. Pores are about 10 times larger than a typical microbe, so this would allow space to form the first cells. Later still, DNA would have evolved from RNA, while proteins proved to be better enzymes than RNA. Proteins that then evolved to actively pump ions across the membrane would allow cells to maintain their own gradients for generating energy and enable them to leave the confines of the pores. “The free-living cell is to me something that can replicate and harvest energy from the environment using chemical reactions that are specified by its genes,” says Bill
Martin. But what did the first cells look like? There is no evidence from the ‘RNA world’ because early RNA-based life would have been erased from history. But if metabolism came first, then scientists could gain insights from any ancient metabolic processes that are still being used to synthesise organic molecules. According to Martin, if the fundamental chemistry worked four billion years ago, there’s no reason why it would have changed. “Early life was very similar to microbes we can still observe today.” The most primitive kind of metabolism, says Martin, is one currently used by simple microbes called methanogens, which make methane, and acetogens, producing acetate. So the most ancient organism might have looked like these. Bridging the gap Scientists agree that life had a single origin because the genetic code is shared by every organism. But the order of the evolutionary steps to the first cell will always be controversial. “In evolutionary biology, it’s always about bridging the gaps,” says Martin. “The gap between us and chimpanzees is small. Back to fish, then down to sponges and simple animals, we can sort of imagine that. But the transition from carbon dioxide, water and rocks on the early Earth to living things is very difficult. We know it happens – so the question is not if, just how.” JV Chamary is a doctor of evolutionary biology and Features Editor for Focus magazine in the UK.
Science photo library x2. illustration by paul wootton
The first organism might have looked like a methanogen, a simple microbe with an ancient metabolism
SCIENCE
find out more E Life Ascending: the ten great innovations of evolution by Nick Lane (Profile, 2009) E http://bbc.in/LifeEarth BBC Nature’s history of life on Earth
What do you think? What do you think is the origin of life on Earth? Email:
[email protected]
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Life Science
Life on other planets
on other planets
For as long as humans have stared at the stars, we’ve wondered whether we’re really alone in the Universe. Andy Ridgway investigates just how close we might be to finding life on another planet
ack in the mid-1990s, astronomers finally detected planets orbiting other stars. The discovery of these ‘exoplanets’ gave extra resonance to the age-old question of whether there are other inhabited worlds out there somewhere. The trouble is, planets in other solar systems are, understandably, difficult to see. “The problem is not that these planets are fainter than the faintest objects seen by the Hubble Space Telescope,” explains Sara Seager, a planetary scientist at Massachusetts Institute of Technology. “It’s that they are next to bright stars.” A planet’s sun simply drowns out the planet’s light. Instead of trying to capture images of exoplanets directly, NASA’s planet-hunting Kepler space telescope spots stars that dim slightly when a neighbouring planet passes in front of it. To date, it has found over 700 exoplanets. As well as revealing their existence, Kepler can show how far planets are from their sun, which will indicate whether they are within the ‘habitable zones’ where there is just enough heat to sustain life. Kepler detected its first habitablezone planet, Kepler-22b, in December 2011. But to tell whether a planet is occupied, it is also necessary to characterise its atmosphere in order to see whether tell-tale molecules, such as oxygen and carbon dioxide, are present. And, using telescopes here on Earth and in space,
Thinkstock. Illustration by paul wootton
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astronomers around the world are having some success in detecting atmospheric molecules. When a planet passes in front of its star, some of the starlight shines through the planet’s atmosphere. Different molecules in the atmosphere block out different wavelengths of light, leaving a ‘fingerprint’ on the light measurements that astronomers take. In some instances, a planet’s atmosphere can be detected when a planet disappears behind a star and then reappears. In 2008, a team led by Mark Swain at NASA’s Jet Propulsion Laboratory detected methane in the atmosphere of planet HD189733b. It was the first organic molecule detected around an exoplanet. But this planet is a ‘hot Jupiter’ – a gaseous world baked by its nearby star. Since then, the closest scientists have come to characterising the atmosphere of a planet that stands a reasonable chance of sustaining life is the planet Gliese 1214b. A ‘super-Earth’, it is larger than Earth but small enough to be rocky. It’s here that many astronomers are currently concentrating their efforts. But their work is effectively a practice run for when telescopes are developed capable of characterising the atmospheres of planets that could genuinely sustain life. Gliese 1214b is simply too hot. That leap in capability may come in the form of NASA’s James Webb Space Telescope, due to launch in 2018.
large moon
Having a large moon may be important for evolving complex animal life on an Earth-like planet. The gravity of the moon acts like a stabiliser to hold the planet upright, stopping the spin axis swaying too far back and forth over millions of years and playing havoc with the global climate.
Water
Water is an absolute requirement of life as we know it, and oceans provide the perfect wet environment for organisms to develop, but perhaps extremophiles could emerge in much drier environments. Water would soak deep into the rocks of the crust and help to lubricate the movements of plate tectonics.
ozone layer
An ozone layer high in the atmosphere is crucial for protecting land-based plants and animals from harmful ultraviolet radiation from the sun.
Greenhouse gases
Certain molecules in the atmosphere, such as CO2, methane and water vapour, act as greenhouse gases to help trap the star’s warmth. Without this planetary blanket, the whole planet would be a frozen wasteland. And, for complex life-forms like humans, oxygen-rich air is crucial.
Anatomy of a living world What are the fundamental requirements for a planet to host hardy bacteria? And what else might be necessary for more complex life forms to exist? As Lewis Dartnell explains, understanding these needs will help us in the search for life elsewhere in the galaxy
volcanism
Plate tectonics and erupting volcanoes would play a key role in keeping a habitable planet’s climate stable and cosy for life. Together, they act to regulate the amount of atmospheric carbon dioxide (CO2) and thus the greenhouse effect, keeping a finger on the planet’s thermostat.
gas giant
Some scientists think that having a massive planet like Jupiter in the outer solar system would help nurture life on inner Earth-like worlds. The gas giant’s powerful gravitational field would pull in stray asteroids and comets that might otherwise have hit the habitable planet. Microbes living deep in a planet’s crust would be better protected, however.
in the habitable zone
One of the most important factors that determines whether life could ever develop on a world is how closely it orbits its star. Wandering too close would roast the planet’s surface and boil its oceans dry. On the other hand, shying too far away would leave the planet a frozen wasteland. The warm sweet-spot in between is called the habitable zone. Extremophiles living deep underground could possibly survive over a wider range of orbits than we once thought. It is also important, especially for complex life, for the planet’s orbit to be stable and circular.
magnetic field
Our habitable planet would need a magnetic field to act like a vast deflector shield, stretching far out into space. It would deflect the solar wind (a fast stream of particles from the Sun) around the planet. This wind would otherwise blow the planet’s atmosphere away. The magnetic field also protects the surface from cosmic radiation, although bacteria, such as D. radiodurans, could survive elevated radiation levels.
meaning of life
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meaning of life
SCIENCE
Life? What is the Whats the
meaning meaningofof
n Douglas Adams’ The Hitchhiker’s Guide To The Galaxy, a race of hyper-intelligent, pan-dimensional beings get so fed up with their relentless squabbling over the meaning of life that they build a supercomputer to supply the answer. After 7.5 million years, the Deep Thought computer, “with infinite majesty and calm”, finally delivers its verdict: 42. Its creators stare blankly at each other, utterly perplexed. The problem is that they demanded an answer to “the ultimate question of
I
life, the Universe and everything” without bothering to work out what the question was. So now they have an answer that they don’t understand. In the event, an even larger computer has to be built to figure out the nature of the question. The whole enterprise is a farce of comical proportions. As this famous scene suggests, the subject is so vast and deep and overwhelming that any attempt to tackle it could be considered so over-reaching as to be completely absurd. But Adams’ gag is wiser than that. For it also raises the question
of whether ‘What is the meaning of life?’ is a proper question at all or a pseudo-question to which there can be no meaningful answer. Meaning is a matter of language, some say, not objects or events in the world like the lives of daffodils, squid or humans. So the idea that we can even attempt to answer this question rests on a conceptual confusion. And yet, somehow, the question has never gone away. Nor has the size of the challenge dissuaded people from taking it on. On the contrary, over the course of human history, scores of thinkers have E
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Alamy, Thinkstock
The purpose of human existence – if, indeed, it has any – has perplexed thinkers for millennia. Dan Cossins examines the competing, often contradictory theories trying to answer the biggest question of all
Science
meaning of life
E weighed in on the issue, joining the quest to find coherent answers to the most profound and elusive question of all. There is no last word, of course. But the history of our attempts to find one contains illuminating insights.
Corbis, Getty, Rex
Sorry, what was the question? If the nature of the question is important in determining what might count as an answer, then what are we really asking here? A natural interpretation is that we want to know why we are here, which itself encompasses two different aspects: the historical question ‘what are the origins of human life?’ and the forward-looking question ‘what is our purpose?’. For those who believe in theistic religions, the answer to both questions is God, an all-powerful being who created the Universe and fashioned man in his own image. This view of human origins, set out in various creation stories, holds that this supernatural creator
Jacopo Tintoretto’s Creation Of The Animals depicts the day that God is believed, by creationists, to have made birds and fishes
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worked with a deliberate purpose in mind – an intelligent design. For believers, it follows that our purpose here on Earth is to serve or submit to the will of God, to fulfil His divine plan. Only then will we reach heaven, the reward for a meaningful life. From this vantage point, God is the basis for human existence
There also exists a very different view of the origins of life, of course. When Charles Darwin published his theories about evolution by natural selection in 1859, he demonstrated for the first time that life is not the result of some allseeing supernatural force, but the consequence of blind, purposeless natural processes. The whole story,
Charles Darwin demonstrated that life is not the result of some all-seeing supernatural force and the sole source of its meaning. Without Him, or at least without faith in Him, life has no meaning or purpose at all. As Albert Einstein noted in Mein Weltbild in 1934, “To know the answer to the question of ‘what is the meaning of life?’ means to be religious”.
by now well established, begins with the Big Bang some 13.7 billion years ago and zooms up date with the emergence of simple singlecell organisms, which evolved over millions of years into all sorts of complex organisms, including Homo sapiens.
meaning of life
According to evolutionary theory, then, we are here, quite simply, because we evolved. In short, our existence is the result of an accident of nature. What’s more, on the forward-looking question of purpose, the answer must be that, after Darwin, there is no good reason to think we have any ultimate direction or meaning whatsoever. For an acute expression of this idea, consider the account of human evolution put forward by Richard Dawkins in his book The Selfish Gene. Natural selection here takes place at the level of the gene, which renders individual organisms – like us humans – little more than survival machines, biological vessels built from DNA blueprints for the sole purpose of ensuring the survival of genes. So one could argue that – from the biological point of view – if we serve any purpose, it is merely to perpetuate the existence of our genes. Or perhaps there is no purpose at all, as the process of random mutation and replication that underlies evolution has no goal beyond adaptation to the here and now ( see ‘Could Evolution Have Direction?’ ). Meaning in crisis So does the triumph of evolutionary theory mean that life has no meaning? That, roughly speaking, is the conclusion associated with what can broadly be described as the ‘existentialist’ philosophers.
Richard Dawkins sees life as simply the struggle to ensure the survival of genes
For Friedrich Nietzsche, a German thinker of the late 19th century, the rise of science and the increasing secularisation of Europe led to what he called the “death of God”. Without the Almighty, who had served as the basis for meaning for thousands of years, we were plunged into a state of nihilism, where the Universe has no inherent meaning and life is entirely without purpose. “Ultimately man finds in things nothing but what he himself has imported into them,” Nietzsche wrote in The Will To Power in 1888. Influenced by another German, Arthur Schopenhauer, who had previously put forward the idea that we are blinded to our own futility by false consciousness, Nietzsche held the view that all we have are illusions of meaning. He blamed Christianity for convincing us otherwise by insisting that its revelation was nothing more than a consoling myth, and warned that this vacuum was dangerous. The only way to proceed, he argued, was to remove the need for objective meaning, a mirage created by Christian doctrine. Sigmund Freud, working in the first half of the 20th century, also felt meaning was an illusion. Unlike Nietzsche, however, he argued that we will never get beyond this fallacy because the allencompassing experience of parental love creates the enduring idea that life is somehow meaningful. A few decades later, French philosopher Jean-Paul Sartre described human life as a “useless passion” to sum up the feeling that we are pointless, superfluous beings. He also talked of the “anguish, abandonment and despair” that accompanies this realisation. His friend Albert Camus, faced with this supposedly meaningless world, declared that we had to accept and embrace the idea that life was ‘absurd’. The existentialists agreed that there is a crisis of meaning, but it would be a mistake to portray E them all simply as purveyors of
SCIENCE
Could evolution have direction? One philosopher believes the purpose of life to be a push towards greater co-operation Ever since Darwin, the scientific view has been that life is an accident of nature with no ultimate direction or meaning. This is founded on the assumption that evolution is itself directionless. But John Stewart, an Australian-based philosopher and a member of the Evolution, Complexity and Cognition Research Group at the Free University of Brussels, Belgium, has a different view. He argues that evolution is actually headed somewhere, an idea that has implications for the meaning of life. In his 2001 book, Evolution’s Arrow, Stewart puts the case that evolution moves in the direction of producing co-operative organisms on a progressively larger scale. Selfreplicating molecular processes were organised into simple cells, he points out, before communities of these simple cells formed the more complex cell. Collections of these complex cells then formed multi-cellular organisms, some of which organised into co-operative societies. A similar sequence can be seen in humans, he claims, from small family groups and agricultural communities to city-states and nations. Based on this understanding of evolution, Stewart proposes that we humans do actually have a meaningful role: to expand the scale of co-operative organisation in our societies and eventually to form a cohesive, co-operative global society. We are coming to a point where evolution will continue to advance only if we deliberately move it forward, he argues, so the meaning of life lies in this push toward greater collaboration. Most evolutionary biologists disagree, however. Evolution cannot have any sort of trajectory, they argue, because it is a random process in which chance plays a key role. “Replay the tape a million times from [the] beginning and I doubt that anything like Homo sapiens would ever evolve again,” wrote the palaeontologist and evolutionary biologist Stephen Jay Gould, who argued that the development of complex organisms is not a necessary or inevitable outcome of evolution, but an incidental by-product.
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meaning of life
Arthur Schopenhauer refused to look on the bright side of life
“Everything a hunter and everything hunted” Schopenhauer’s singularly squalid view of life was the most despairing of all
Corbis, thinkstock x2
Perhaps the most pessimistic outlook on the meaning of life came from the mind of Arthur Schopenhauer, a German philosopher working in first half of the 19th century. More than any other thinker before or since, he bluntly confronted the idea that human existence may be pointless and worthless in the bleakest way. In his book The World As Will And Representation, published in 1818, Schopenhauer advanced the idea that all reality, including human life, is the product of a voracious, implacable will. Everything we do is driven by what he called the Wille zum Leben (Will to Live), the aimless urge at the foundation of our instinctual drives and our very being. This will is a relentless, directionless force that exists for no other reason than to perpetuate itself, he argues, meaning that all human action is completely futile. In this view, we are no more than helpless instruments of the will’s indifferent push for self-perpetuation – even if we convince ourselves otherwise. For Schopenhauer, the will has tricked us into believing our lives have value and meaning by inculcating within us a mechanism of selfdeception known as consciousness. So all consciousness is false; it exists only to conceal from us the complete pointlessness of our existence. In his eyes, a cold hard look at human history could lead to no other conclusion. Our story is one of such unbroken misery and exploitation that only those deceived by the will could consider life worth living. For there is no goal or direction, he wrote, only “momentary gratification, fleeting pleasure conditioned by wants, much and long suffering, constant struggle, bellum omnium [the war of all], everything a hunter and everything hunted, pressure, want, need and anxiety, shrieking and howling; and this goes on in saecula saeculorum [eternity] until once again the crust of the planet breaks.”
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E meaninglessness. For Sartre, as for most atheists today, the fact that life has no significance or direction imposed from the outside does not mean that it has no meaning at all. It just means that life does not come with a pre-assigned meaning, a conclusion that clears the way for us to make whatever sense of it we can. In other words, as Nietzsche implied, if our lives have meaning, it is something we endow them with, not something with which they come pre-packaged. For many, this idea is deeply liberating. They argue that just because we’re fashioning it for ourselves does not make this meaning inferior. “An objective meaning – that is, one which is inherent within the Universe or dependent upon external agencies – would, frankly, leave me cold,” wrote the American philosopher ED Klemke in 1981. “It would not be mine ... I, for one, am glad that the Universe has no meaning, for thereby is man all the more glorious. I willingly accept the fact that external meaning is non-existent ... for this leaves me free to forge my own meanings.” This is the subjectivist view. It holds that meaning only makes sense in terms of what the individual finds meaningful. If meaning is constructed rather than prefabricated, they contend, each
Subjectivists view meaning as defined by the self, so pursuits like mountain-hiking could inspire very personal perspectives
of us can interpret life in very different ways. So one person might get meaning from hiking in the mountains while another finds it by building model trains. As the contemporary British philosopher Julian Baggini puts it, “The search for meaning is essentially personal.” Put bluntly, this is the meaning of life as private project. Happiness and human flourishing Others find this view distinctly unsatisfactory. They argue that there must be something independent of the mind of the individual, something about which we have common beliefs, which constitutes meaning. After all, most of us would agree that some things are inherently more meaningful than others. Creativity and morality, for example, are generally held to confer meaning; chewing gum or trimming toenails are not. What’s more, searching for meaning is not something that people occupy themselves with in a vacuum, but in dialogue with a determinate world discernable to all, so any proper answers must convey significance beyond the realm of the individual. They must mean something to others. So if there is some objective purpose or meaning in life, where do we find it? Perhaps it’s not in the story of our origins but the
meaning of life
Is the happiness deriving from loving family relationships the best that we can expect from life?
our relationships with family and friends. So for Eagleton, Aristotelian happiness and love – as a kind of reciprocity that enables happiness and human flourishing – are ultimately complimentary. The meaning of life to Eagleton, then, is a collective endeavour in pursuit of Aristotelian happiness through the reciprocity of love. “One could do worse, surely, than propose such a situation as the meaning of life,” he writes. “Both in the sense that it is what makes life meaningful, and – more controversially – in the sense that when we act in this way, we realise our natures at their finest.”
Creativity and morality are generally held to confer meaning; chewing gum and trimming toenails are not commonly held goals that make our lives worth living? We are not short of candidates here. For Plato, the ancient Athenian thinker who confronted the question over two millennia ago, it is the pursuit of the highest form of knowledge, known as the Good, with intelligence and reason. In other words, in Plato’s view, contemplating the meaning of life is the meaning of life. For Aristotle, a student of Plato, the fundamental goal in human life is happiness. For happiness is not a means to something else, like money or power, but an end in itself – and our desire for it seems to be an unavoidable part of our nature. But Aristotle’s definition of happiness, articulated in his Nicomachean Ethics, was not an emotion or a state of mind; it was a practical way of life. Happiness and human flourishing – the best translation of Aristotle’s original Greek term ‘eudaimonia’ – is attained in the pursuit of activities
SCIENCE
that themselves have good at their end. It is part of a practical, social form of living and working that creates an inner disposition, rather than an attitude itself. In Aristotle’s view, then, happiness and well-being come when we pursue something we think is good for us. It is the act of doing as much as the end in itself that creates ‘eudaimonia’. So the common goal – and by extension the meaning of life – is the pursuit of happiness through the creative fulfilment of our human talents and potential. In his book The Meaning Of Life, British literary critic Terry Eagleton also throws love into the equation. Not romantic love, but the love for humanity defined by the Greek word ‘agape’, which for him is the way we are able to reconcile our search for individual fulfilment with the fact that we are by nature sociable animals. After all, for most people, life is made meaningful by
Final answer? The oldest question will never be wrapped up once and for all, of course. If there is actually one solid conclusion to surface from the ageold quest to discover the meaning of life, it is exactly that. Despite the concerted efforts of some of the greatest thinkers in history, not even the most detailed and refined arguments have delivered a final, unifying answer. Ultimately, as the hyperintelligent creators of the supercomputer Deep Thought found to their enduring irritation, the meaning of life is a question that will never go away. Dan Cossins is a British freelance journalist based in the United States who specialises in science and history.
find out more E The Meaning of Life: a very short introduction by Terry Eagleton (Oxford University Press, 2008) E What’s It All About? philosophy and the meaning of life by Julian Baggini (Granta, 2005)
What do you think? Does life have a higher purpose or is it just a series of random events? Email:
[email protected]
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robotics
Some of evolution’s finest designs are being mimicked to build robots with incredible abilities. Duncan Graham-Rowe takes a close look at the machines that can climb vertical walls, sprint and eat raw sewage…
ay the word ‘robot’ and it’s hard not to think of shiny, mechanical droids, rolling around busily beeping and whirring like R2-D2. But the fact is, if robots are ever to stand a chance of becoming a major part of our world, they are going to have to first lose the dustbin-onwheels image and take on something altogether more organic. After decades of being ingrained into our psyche, the classic mechanical notion of how robots should look, move and function is now undergoing a radical transformation as roboticists – from universities and private companies alike – are increasingly taking inspiration from the animal kingdom. After all, why try to engineer solutions to problems that Nature has already spent millions of years of trialand-error perfecting? So, out goes the wheel, the gear and the battery pack, to be replaced by leg, muscle and stomach. This transformation is giving rise to a new class of robot that is faster, more agile and dexterous, and ultimately better equipped to cope with life among us. These ‘biobots’ could even end up sitting down to dine with us. But the real prize is the growing hope and belief that mimicking biological systems could dramatically accelerate the quest for true artificial intelligence. By interacting with the world like humans, robots will finally start to think like us. Here we take a look at five pioneering biobots that are leading the charge in this merging of E biology and robotics.
patrick knab
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>Based on
human being
ECCEROBOT The robot with muscles, bones and tendons… and the ability to learn If you were to remove someone’s skin, as though creating a Gunther von Hagens exhibit, what you’d be left with is something resembling Eccerobot. While most androids are made of conventional mechanical joints and precision motors covered with a rubbery skin-like coating to make them look human, Eccerobot’s human-like qualities are more than skin deep. “Eccerobot has a torso and arms made up of bone-like pieces – many copied from Gray’s Anatomy,” says Prof Owen Holland, a roboticist at the University of Sussex who is a lead investigator on the project. “These bones are held together and moved by soft tissues in the form of rubber bungees connected by cords to the spindles of electric motors.” Winding or unwinding the cords stretches or relaxes the bungees, just as we stretch or relax our muscles. These artificial muscles then pull on the thermoplastic bones to create movement. The result is movements that have a human quality about them, says Holland. “When a traditional robot moves a joint, it has no effect on the rest of its body,” he says. This is why they move in such a characteristically stiff ‘robotic’ fashion.
But with Eccerobot (Embodied Cognition in a Compliantly Engineered Robot to give him his full name), whenever part of him moves, the movement is distributed throughout the whole body. The consortium of robot labs across Europe that developed Eccerobot is currently looking at how this sort of musculoskeletal robot could be used in manufacturing. It is also creating a boysized version of Eccerobot, called Roboy, who unlike his older sibling, will have legs and the ability to walk. The hope is to have a prototype strutting around by March of this year.
mind and body One of the main motivations behind Eccerobot’s development was to explore the link between movement and cognitive ability. By combining data from sensors across the robot’s body with information from his camera, or ‘eye’, he can learn how movements in one part of his body will affect another and what interactions with the outside world, such as grasping a coffee cup, ‘feel’ like. This is a form of low-level intelligence, says Professor Rolf Pfeifer, director of the University of Zurich’s Artificial Intelligence Laboratory and another of the lead investigators on the project. “There is a tight connection between sensory-motor processes and cognition, thinking and intelligence,” says Pfeifer. For a robot butler to be of any real use, it would need to be able to respond to different situations and interact with its environment. Eccerobot provides the first clues as to how that could be achieved.
how it works Muscles, tendons and a skeleton create a compliant, human-like form of movement. By mimicking human motion, the hope is to create robots with richer data streams from their sensors, ultimately making them smarter.
Artificial tendons, muscles and bones make Eccerobot move in an eerily human manner
Science
robotics
>Based on
big cat
CHEETAH The sprinting ’bot that’s the fastest mechanical thing on four legs If you want to build a robot that can run fast, what better to model it on than the cheetah – the fastest land animal. That’s precisely what US robotics firm Boston Dynamics has done, creating a four-legged sprinting ’bot that is anatomically inspired by its namesake. With the
help of Professor Alan Wilson, an expert in fast-moving mammals at the Royal Veterinarian College, London, the company identified traits that enable cheetahs to reach such high speeds. Boston Dynamics, founded by former MIT professor Dr Marc Raibert, had a YouTube hit with one of its creations, Big Dog, a four-legged robot mule that has the ability to stay upright even when given a hard shove from the side. But the Cheetah ’bot is all about speed. “We noticed that the cheetah’s back flexes and unflexes, allowing it to increase its stride length without having longer legs,” says Raibert.
A cheetah’s back is so flexible that it enables its hind feet to be thrust underneath its chin when it sprints. This means its feet are on the ground for longer, allowing them to support more weight – a crucial factor dictating maximum running speed. “So we designed the Cheetah robot to have an articulated back,” says Raibert. Cheetah ’bot also maintains a form of dynamic stability that many creatures use when running, where the body is effectively in a continual state of falling forwards. Earlier this year, the Cheetah ’bot broke the world speed record for a legged robot, thrashing along a treadmill at 29km/h (18mph) and
smashing the previous record of 21km/h (13mph) set over 20 years ago. The target is about 48km/h (30mph) and last October the Cheetah ’bot broke its own record, hitting 45km/h (28mph). This could lead to a future of fleet-footed robots delivering supplies to frontline troops, or carrying medication into an earthquake zone. But before doing this, Cheetah needs to stand on its own four legs. It currently runs with a support boom holding it in place, while its power is supplied through a cable. Cheetah is being developed so it has on-board power and a more advanced control system.
boston dynamics, adam gasson
Having broken the speed record for a legged robot, Cheetah could soon be helping out frontline troops
how it works With a flexible spine that extends the reach of its legs, Cheetah is able to take long strides. Inspired by data taken from real cheetahs, this is the fastest running robot in the world.
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robotics
Ragter than a plug socket, EcoBot III’s energy comes from a diet of dead flies, prawn shells, rotten fruit and even neat urine that it digests in its stomach. It then uses the power it has created to trundle around. With its wheels and classic droidlike appearance, at first glance there’s nothing particularly biological about EcoBot. But then the smell hits you. Containing 48 microbial fuel cells, this robot may have personal hygiene issues, but it is blazing a trail for self-powered robots. Even NASA has taken an interest in using microbes to power robots.
SCIENCE
>Based on
cow’s stomach
Ecobot III A robot with real guts, which it can use to digest almost anything 1
1. Feeding The robot first dines on its diet of sewage water, dead flies or other forms of ‘food’, which it accesses via a dispenser. This food passes into 48 separate anaerobic digestion chambers.
FULL STOMACH EcoBot III has been developed at Bristol Robotics Laboratory, a joint venture between the University of Bristol and the University of the West of England. Each of its fuel cells – its cow-like stomachs – contain a culture of hungry bacteria that happily feed on organic matter. In the resulting reaction, electrons are released which then drive an electrical circuit that powers the robot. By giving the robot the intelligence to feed itself through a dispenser, EcoBot III was able to survive for up to seven days autonomously. But rather than looking to create an army of flesh-eating ’bots bent on world domination, the Bristol lab’s aim is to develop robots that can happily graze on the organic matter around them – and our waste products – and use the resulting energy to get around, monitoring the environment. An inevitable consequence of a digestive system is that EcoBot III eventually has to dump its waste somewhere. So in the lab at least, it has its own litter tray.
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2. digestion Bacteria in the anode chambers of the microbial fuel cells (MFCs) feed on the organic matter, metabolising it. Chemical reactions take place that cause hydrogen protons and electrons to be given off. The microbes, which are embedded within the surface of the carbon anode, pass electrons to it. The electrons then flow through a circuit to a cathode in a separate chamber, creating an electrical current in the process. At the same time, the hydrogen protons pass into the cathode chamber that contains water. Here, oxygen dissolved in the water combines with the hydrogen protons and hydrogen electrons to produce more water, a by-product of the MSC that is given off as steam.
3. locomotion The electricity from each MFC is used to power the robot, enabling it to move about on wheels and feed again when it gets hungry.
how it works
4. Waste disposal EcoBot creates its own waste matter. This is processed in the waste evacuation pump, a peristaltic mechanism contained in a blue housing that mimics the movement of the intestines.
Microbes in a series of cow-like stomachs break down food, producing electricity that powers EcoBot III. It is then able to move around to find its next supply of junk food. 3
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robotics
>Based on
human hand
biotac An artificial fingertip with a better sense of touch than ours
The fingerbot, or BioTac to give it its official name, has artificial bone, skin and even fingerprints to mimic, and even improve upon, our sense of touch. Despite the speed and efficiency with which the $20 billion (£13 billion) a year industrial robotics sector can manipulate objects, these robots essentially do so blindly with no real sense of touch, says Professor Gerald Loeb, an expert in biomimetics at the University of Southern California, where BioTac has been developed. The disembodied finger, developed by Loeb and post-graduate colleague
Dr Jeremy Fishel, largely mimics the human finger. “The trick is not to blindly copy but to extract principles of operation and adapt them,” says Loeb. The results are impressive. BioTac can correctly identify materials 95 per cent of the time and distinguish items that human volunteers were unable to using their sense of touch alone. BioTac’s elastic skin is separated from a bone-like plastic by a liquid filling, much the same as in our fingers. As the artificial finger slides over a surface, the skin vibrates in characteristic ways and these vibrations are
picked up by a hydrophone within the bone. A fingerprint and fingernail enhance and relay the vibrations. The vibrations are analysed by algorithms designed to capture the thought processes humans use when characterising the texture of surfaces. Other types of sensor, which can detect heat and pressure, aid the identification process. Fortunately for BioTac, the only sensation it’s incapable of experiencing is pain. Loeb and Fishel are partners in a company called SynTouch and are selling BioTac sensors to the manufacturers of industrial robots and prosthetic hands.
how it works
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The internal structure of a human finger is replicated in a robotic digit. It can sense what it is touching from the vibrations generated as it passes over a surface.
Machines get touchy feely: a robotic hand incorporating the BioTac finger tips
robotics
SCIENCE
>Based on
GECKO
how it works
TBCP-II
Coating the robot’s tank tracks with microscopic hair-like structures called setae makes it possible to mimic the way geckos can stick to, and move about on, walls and ceilings.
Creating a robot that can climb walls has obvious benefits. Imagine it climbing a skyscraper to clean its glass or silently negotiating its way through a dangerous building in a war zone. But achieving this goal has been fraught with difficulty. If the adhesive the robot uses is wet, it will leave a trail. So a dry adhesive is a must. Suction could be used, but it requires a large amount of energy and magnets would limit climbing antics to
metals. So researchers at Simon Fraser University in Canada have taken inspiration from a real-life wall crawler, the gecko. Their gecko ’bot, named TBCP-II, looks nothing like a gecko, having two pairs of tank-like treads to get about. But what it does have is geckolike hairs on these treads called setae. In a gecko, these setae are themselves covered with tiny structures called spatulae. Molecules on the surface of
these are attracted to molecules in the surface of the structure that’s being climbed by Van der Waals force – the attractive force between molecules. While the force generated by each spatulae isn’t strong, there are so many they can hold geckos to a wall. The team created artificial setae that generate sufficient force to make gecko ’bot stick. An articulated spine also allows it to negotiate transfers around corners and from wall to ceiling.
The gecko-like robot TBCP-II could be hanging around on a wall near you soon
university of southern california, simon fraser university
This tiny tank has the ability to scale vertical walls
Duncan Graham-Rowe is a science and technology journalist.
find out more E Watch a video of Cheetah ’bot getting into its stride; http://youtu.be/d2D71CveQwon E Eccerobot shows off his handling skills in this video; http://youtu.be/cI9H4FoA0b4 E Watch the robotic gecko TBCP-II scale new heights; http://youtu.be/tont-BzM1II April 2013
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Asoka and his legacy
Himanshu Prabha Ray elucidates on Emperor Asoka's remarkable vision and beliefs that steered his political ideology
R
123rf.com
esolved that the National Flag of India shall be horizontal tricolour of deep saffron (kesri), white and dark green in equal proportion. In the centre of the white band, there shall be a Wheel in navy blue to represent the Charkha. The design of the Wheel shall be that of the Wheel (chakra), which appears on the abacus of the Sarnath lion capital of Asoka. This Resolution was proposed by Pandit Jawaharlal Nehru, the first Prime Minister of independent India and passed in the Constituent Assembly on 22 July 1947, just
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prior to India’s Independence. In addition to the chakra represented on the Indian flag, the Lion Capital of the pillar excavated at Sarnath was chosen as an emblem of India to be represented on money, official government stationery and so on. The Mauryas reigned for 137 years according to the Puranas; and historians generally agree that Asoka ruled from 274/3 to 232/1 BC. The question arises: what was special about Asoka and his rule that brought him to the centre stage of modern political thought in India? A short answer would be: his
inscriptions, which were deciphered in 1837 by James Prinsep (1799-1840). All the pillar edicts opened with the phrase; thus speaks Devanampiya Piyadassi. Who was Devanampiya Piyadassi? Nineteenth century archaeologists had difficulty in identifying the king as Asoka and this issue was finally resolved only after the Mahavamsa written in Pali in Sri Lanka had been consulted. Clearly the relevance of Asoka was not limited to Indian History, but extended to writings in other countries of Asia, such as Sri Lanka, Myanmar, Thailand, China and Tibet.
Asoka
Asoka’s grandfather Chandragupta had founded the Mauryan dynasty and established its rule in large parts of the Ganga valley and the north west, but it was Asoka who established his supremacy over the subcontinent, as evident from his edicts. Asoka’s epigraphs, inscribed on pillars and rocks, are found over an extensive area from Gandhara in the north-west (now Pakistan) to Karnataka in south India. In many of the edicts, Asoka speaks to his subjects in the first person and addresses them directly, while others refer to the king in the third person and articulate his ideals of dhamma. In rock edict XIII Asoka expresses remorse at the loss of life that occurred during the conquest of Kalinga, which took place in the eighth year of his reign. Interestingly this edict does not occur in Odisha. In his minor rock edicts, Asoka
refers to himself as a Buddhist lay devotee and communicates his desire that Buddhism percolates down to include elephant-trainers, charioteers, teachers and scribes. In the past, scholars have constantly tried to reconcile information contained in the edicts with those from other sources, such as the biography of Asoka in Buddhist texts, like the Asokavadana written five hundred years after Mauryan rule in second century AD in Sanskrit. In the Asokavadana compiled in north western India, Asoka is described as an ugly prince who quelled the revolt in Taxila and ascended the throne after killing his brothers. His fierce and malevolent nature was tamed by the Buddhist monk Upagupta who is said to have converted him and inspired him to visit places associated with the life of the Buddha. Asoka then built eighty-four thousand stupas
History
throughout his empire. The text also includes the tragic story of his son Kunal who was blinded by a jealous stepmother. A second text that popularized the story of Asoka was the Ceylonese chronicle, the Mahavamsa dated to the late fourth or early fifth century AD. Its authorship is attributed to a Buddhist monk Mahanama who wrote under the patronage of a Sri Lankan king. In this chronicle the emphasis is on the purification of the Sangha by Asoka and the dispatch of Buddhist missionaries not only to different parts of the subcontinent, but also to Suvarnabhumi, and most of all to Sri Lanka. There are references to the Sri Lankan King Devanampiyatissa (250-210 BC) being re-consecrated by envoys of Asoka. The text does not mention Asoka’s ugliness or his violent nature. There are other major variations E April 2013
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HIstory
Asoka
Timeline Around 250 BC Asoka built stupas, rock edicts and erected pillars bearing his inscriptions
3rd BC:
The lion pillar at Kolhua, Vaishali, was erected by Asoka to commemorate the last sermon of Buddha. It is the only complete standing pillar in the country.
8th regnal year:
In rock edict XIII Asoka refers to contemporary kings and expresses regret over the killings in Kalinga.
20th regnal year:
It is believed that in 250 BC, Asoka visited Lumbini in Nepal where Buddha was born. The Asoka Pillar was erected to commerate his visit to the site.
27th regnal year:
Musee Guimet, wikipedia X3, virtualtourist.com
Asoka erected a 13m high sandstone pillar in Topra, Haryana. During his reign, King Firozeshah Tuglaq (r. 1351-1388), had the pillar shifted to Delhi.
E as well. In the Asokavadana, Asoka is said to have been born one hundred years after the passing away of the Buddha, while in the Mahavamsa, the Mauryan king was consecrated 218 years after the Buddha’s nirvana. The Mahavamsa associates Asoka with holding the third Buddhist Council at Pataliputra and of cleansing the Sangha of false beliefs by defrocking at least sixty thousand monks. Another tradition that is mentioned in the Mahavamsa, but scarcely occurs in the Asokavadana relates to the despatch of missionaries by Asoka to different regions. 54
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Asoka... an ugly prince who quelled the revolt in Taxila and ascended the throne after killing his brothers The memory of Emperor Asoka continued to be invoked in Sanskrit, Pali and Prakrit writings of Buddhist, Jain and Hindu affiliation, throughout the historical periods. For example, the Rajatarangini, a chronicle written in Sanskrit by the Kashmiri brahmana poet, Kalhana, in 1148/49 AD attributes to Asoka the foundation of Srinagari, the old capital, identified with a site in the vicinity of the present city of Srinagar in Kashmir. Asoka figures as the patron of the ancient and famous Saiva shrine of Vijayesvara. Jain sources also know of Asoka, but he is not as central in Jain accounts as he is in Buddhist ones, instead Jain histories focus more on Asoka’s grandfather and founder of the dynasty, Chandragupta, who they say became a Jain. The Digambara historians credit him with leading a migration south to avoid a great famine, and eventually dying in meditation at the holy shrine of Sravana Belgola in the present south Indian state of Karnataka. One of the terms that Asoka used almost a hundred times in his inscriptions is dhamma or dharma and perhaps for the first time dhamma became a key concept in political theology. A comparison of the Asokan edicts with contemporary descriptions of kingship as enshrined in the Dharmashastras and the Arthashastra make it obvious that the dhamma of the edicts was not doctrinal and did not adhere to any one religion, but denoted universal law and righteousness. The edicts included the injunction to: “Obey mother and father, obey the teachers; have mercy on living beings; speak the truth and propagate the dhamma”. At the same time, Asoka praises ceremonies performed for religious purposes, but decries those performed on the occasion of births, illnesses, and
weddings (rock edict IX). There are references to several religious ceremonies in his inscriptions, such as visits to the Bodhi tree and chanting of Buddhist scriptures, among others. Rock edict VIII dates Asoka’s dhammayata (pilgrimage) to Sambodhi or the sacred Bodhi tree at Gaya ten years after his consecration. In the Bairat rock edict, Asoka recommends the study and reflection of seven texts of the Buddhist canon. Asoka insisted that his dhamma was based on ancient tradition, which had been ignored by past kings who governed unjustly. He termed his dhamma ‘ancient custom’ and proclaimed the revival of tradition. What is undeniable is the contribution of Asoka in providing it centrality within political thinking. From the Mauryan period onwards the righteous king became a role model for rulers to emulate. As evident from the frequent use of the term in his edicts, Asoka redefined it to make it almost entirely an ethical concept. There is no doubt that scholars will continue to debate many of these issues, and the history of Asoka will continue to enrich and impact our understanding of the present. Prof Himanshu Prabha Ray of the National Monuments Authority, New Delhi, focuses on the Archaeology of Religion, the History of Archaeology and the Maritime History and Archaeology of the Indian Ocean.
find out more E Patrick Olivelle, Janice Leoshko and Himanshu Prabha Ray edited, Reimagining Asoka: Memory and History, Oxford University Press, New Delhi, 2012. E John Strong, The Legend of King Asoka, Princeton University Press, Princeton, 1983. E Romila Thapar, Ashoka and the Decline of the Mauryas, Oxford University Press, New Delhi, 1960.
Asoka Maurya was denoted as a chakravartin - a term used in ancient India to describe an ideal universal ruler, who rules ethically and benevolently
Accidents will happen
Scientific discoveries don’t always happen by design. Nige Tassell reveals 10 breakthroughs in which serendipity played its part
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teflon
Dupont, Alamy, SCIENCE PHOTO LIBRARY, SCIENCE & SOCIETY PICTURE LIBRARY, MARY EVANS PICTURE LIBRARY, GETTY X3, PRESS ASSOCIaTION X2
In 1938, a young American scientist called Roy J Plunkett was researching new refrigerants for the DuPont Company and was storing tetrafluoroethylene gas in cylinders at low temperatures. When he opened the cylinders, the gas had disappeared, but the containers still weighed the same. Intrigued, Plunkett sawed a cylinder in half and a white powdery substance fell out. Finding it to be resistant to heat and that few other substances would stick to it, he realised the substance – polytetrafluoroethylene – could have widespread use.
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Penicillin
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Dynamite
One accidental discovery that has saved millions of lives came about as a result of bad housekeeping. In 1928, London-based Scottish scientist Alexander Fleming accidentally left a tray of staphylococcus bacteria uncovered. After a few days, bacterial growth was visible, save for a patch of mould that was stopping the bacteria’s spread. A substance produced by the mould, dubbed penicillin by Fleming, was subsequently found to kill off much harmful bacteria and became the world’s most used antibiotic.
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Saccharin
A Russian chemist called Constantin Fahlberg was, in 1878, working at Johns Hopkins University in Baltimore, analysing the chemical compounds of coal tar. One day, he neglected to wash his hands when he left work and, eating his dinner at home, discovered that the compound sulphamine benzoic that remained on his fingers had a sweet taste. He quickly – and privately – applied for patents in several countries and saccharin made him a wealthy man.
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celLOphane
In 1900, Swiss engineer Jacques E Brandenberger was eating lunch when a fellow diner spilled some wine, causing the tablecloth to be replaced. Brandenberger decided to invent a waterproof tablecloth, but the application of a liquid viscose made the covering too stiff. The coating did, however, peel off as a piece of transparent film. A new product, with strong commercial potential, was born.
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The Swedish chemist Alfred Nobel owned a factory manufacturing nitroglycerin, an explosive deemed too unstable for widespread use. One day in 1867, he dropped a vial of it on the ground, but was intrigued when it didn’t explode, possibly because it had mixed with sawdust on the floor. When Nobel added a further stabiliser – silica known as kieselguhr – mass production of reliable gunpowder could begin.
accidental discoveries
Charles Goodyear demonstrates how his discovery of vulcanised rubber came about by chance
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Vulcanised rubber
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Vaseline
History
In its natural state, rubber can rot and smell. For many years, American inventor Charles Goodyear tried to make a more durable substance. In 1839, he finally found success – by accident. Inadvertently brushing rubber powder and sulphur from his hands, it landed on a hot stove. The melting rubber reacted with the sulphur and became vulcanised – leading to Goodyear becoming a pioneer in the tyre industry.
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Viagra
In the early 1990s, British scientists employed by the Pfizer pharmaceutical company were carrying out tests on a new compound aimed at treating angina. The trials were unsuccessful, but many of the participants reported experiencing penile erections. After further trials, Pfizer took the drug Sildenafil citrate – by now branded as Viagra – to market. By 2000, Viagra accounted for 92 per cent of worldwide sales for prescribed erectile dysfunction pills.
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The microwave oven
In 1945, Percy Spencer, an employee of the American defence contractor Raytheon, was standing in front of a magnetron when the chocolate bar in his pocket melted. Intrigued, Spencer placed some popcorn in front of the tube. It instantly popped across the room. The commercial potential of the discovery was pounced upon; within two years, Raytheon were marketing the first microwave oven.
In 1859, a 22-year-old Brooklyn chemist called Robert Chesebrough visited the Pennsylvanian oil fields, eager to break into the profitable industry. The oil workers told him about a sticky substance called ‘rod wax’, a by-product of the extraction process that often caused the drilling rigs to seize up. A redeeming feature was that it seemed to speed up the healing of cuts and burns. After ten years of testing, Chesebrough managed to extract usable petroleum jelly. Vaseline was born.
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Super glue
In 1942, Kodak employee Harry Coover was making plastic gunsights for military planes, but the solution he created – later named cyanoacrylate – was far too sticky. A decade later, a colleague developing jet fighter canopies used the discarded solution and its phenomenal gluing powers were rediscovered.
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Portfolio Orchids One of the most prolific families of flowering plant on the planet, the orchid deploys a host of ingenious tactics to ensure its success Photographs by Christian Ziegler
deceptive beauty Sardinia, Italy There are over 35,000 species of orchid known to science, making it one of the largest families of flowering plant in the world, and new species are still being discovered. It thrives in a range of diverse habitats around the world, from the dense cloud forests of Central America to southern Sardinia – the location of this striking pink butterfly orchid (Orchis papilionacea). The plant’s showy appearance encourages bees, its main pollinators, to investigate deep inside its flowers, but it does not produce nectar, meaning the bees help it out with no gain for themselves.
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NATURE
Portfolio NATURE
PORTFOLIO
treetop VISTA Rio Platano, Honduras G Clinging to the branches of a mangrove tree, Myrmecophila brysiana is an epiphytic orchid. It attaches itself to a host plant, and takes moisture and some of its nutrients from the air instead of the soil. Its hollow stems, called pseudobulbs, often house colonies of ants. The insects deposit organic debris as they harvest nectar from the flowers and distribute pollen. The debris provides the orchid with an alternative source of nutrients.
fly trap E Masdevallia caloptera, shown here in full bloom, uses its impressive display to lure its main pollinator – passing flies. This specimen is from the highlands of Peru and is only found at altitudes of 1800-2600m (5906-8530ft) in the dense South American jungle.
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playing dead Western Australia The elegant red beak orchid (Pyrorchis nigricans) is a common sight in eucalyptus woodlands. It typically flowers once bush fires have cleared the undergrowth, so as to avoid competition from rival plants. Although pollinated by insects, it is adverse to attention from other animals and uses a unique defence mechanism to avoid them. When the seeds are ready to disperse, the plant turns completely black – causing local people to refer to it as the undertaker orchid – and blends in with surrounding burnt twigs. The resulting dead appearance discourages any grazing animals.
magic mushrooms Central America E Dracula wallisii, found in cloud forests, relies on both appearance and scent to attract its preferred pollinators – fungus gnats. The orchid’s central lip looks rather like a mushroom, and it also emits a fungus-like scent that is completely irresistible to the tiny gnats. The gnats collect and distribute the orchid’s pollen while laying their eggs.
Portfolio
NATURE
false love Sardinia Bee orchids use sexual deception to attract pollinators. They mimic the appearance of female insects, and also imitate their pheromones. Here, an eager Andrena nigroaenea orchid bee is attempting to mate with a deceptive Ophrys fusca bee orchid flower.
pollinator and prey Central and South America Like many species of Latin American orchid, Gongora tricolor relies exclusively on orchid bees for pollination – and, inevitably, some of the bees’ predators have learned that the plants are a good spot to linger in the hope of a meal. Here, an exquisitely camouflaged crab spider from the Thomisidae family lies in wait.
The photographer Christian Ziegler is a German photojournalist and biologist who specialises in tropical rainforests and their inhabitants. His latest book is Deceptive Beauties: The World of Wild Orchids (2011, University of Chicago Press).
find out more E www.naturphoto.de Christian Ziegler’s official website April 2013
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Michael Fogden/osf
The gharial’s remarkable snout takes crocodile design to the extreme. Sadly, such impressive weaponry has failed to protect the species from a dreadful decline. Romulus Whitaker details his experience
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The gharial’s snout is far more slender than that of other crocodilians
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Gharials occupy the same role of top predator in India’s rivers that tigers hold in its forests
Lined with sharp teeth, the gharial’s incredibly long, slim jaws are ideal for catching fish Razor-sharp teeth stop fish slipping away
adolescence, at about the age of 10 or 12, a wart-like appendage begins growing on the tip of his snout. This is the ghara (Hindi for ‘pot’). It covers and presses down on the nostrils like a lid on a saucepan. When the male breathes out forcefully, it produces a flatulent noise that carries across the water. The politest term I can come up with for this sound is ‘buzz-snort’. It serves two purposes – to attract females and warn off rivals.
Recently, my team and I heard the buzz-snort in action near Rajghat on the Chambal River in north India. A large male was patrolling the water, and we heard the territorial clap of his jaws snapping together. The gharial is the only croc to advertise its presence in this way under water, and many biologists think this could be a method of stunning prey as well as marking territory. It was a chilly winter morning, and when the male surfaced E April 2013
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Anup shah nature pl.com, masterfile, Anup Shah/naturepl.com
he Sun blazed overhead. It was midday and we had been walking for hours. I wanted to believe that the faint wisp of blue in the distance was the River Padma – our destination – but I feared it might be just a mirage. Finally, a ribbon of cobalt swam into view and, exhausted, we clambered to the brow of the high bank. There in the water below us, we saw a crocodile with an unfeasibly long, slender snout. Uncertain whether it was indeed a gharial or an illusion brought about by the heat, we headed down towards the river. The gharial’s sleek body glistened. She seemed unafraid, and we guessed she was guarding eggs buried in the sandbank. Instantly revived, we dug until we found the nest. Gently, we extracted the eggs, so we could rear the young safely in captivity and release them back into the wild. The mother gharial watched suspiciously but didn’t attack us. That was in the mid 1980s. We didn’t know it then, but this may have been the last time wild gharials nested in Bangladesh – a symptom of the species’ decline across its entire Asian range. The problem was that no one at the time knew enough about this unusual crocodile to be able to help it survive. This is what has prompted me to work as much as I can in gharial country – specifically India, Bangladesh and Nepal. My conservation work with reptiles began in the 1970s when I was working at the Madras (now Chennai) Snake Park, and later the Madras Crocodile Bank, which I and others founded in 1976. I spent the ’70s and ’80s either performing or initiating the first reptile surveys in India on crocodiles, sea turtles and freshwater turtles. The surveys showed that all of India’s three species of croc – the gharial, the marsh or mugger crocodile and the saltwater crocodile – were in trouble. The gharial is one of the largest of all crocodilian species, with adult males reaching up to six metres (20 feet). What sets it apart from all other crocodilians is its incredibly long, slim snout, which it wields like a pair of chopsticks. Its slender jaws, lined with sharp teeth, are highly agile, ideal for catching the fish which form the bulk of its diet. But the jaws of males have another highly specialised function that’s unique among crocodiles. When a male reaches
Nature
Romulus Whitaker, ramesh pandey, Suresh Chaudhari
Science NATURE
Conservation
Gharial numbers are now critically low and are being closely monitored
Conservation
gharial mothers lead their babies to water, rather than carrying them in their needlesharp jaws. This mother extracted most of her brood without mishap, but as she dug the sand with her front feet, she accidentally flipped out a baby along with the clods of earth. The baby landed by her hind feet and she then ‘back-heeled’ it through the air and into the water with a splash.
The gharial’s narrow choice of habitat and diet has largely contributed to its downfall Fortunately, she excavated the rest of the nest without jettisoning any more of her brood, before turning around and sliding into the river. The 36 babies followed, rather like long-snouted ducklings. Alerted by all the activity, the father lurked nearby. When he swam close to the family, the hatchlings climbed onto his head. Both adults then guarded the youngsters. This behaviour is no doubt echoed in the wild, and it’s likely that family groups are only split up when monsoon rains wash the juveniles away down river. Appetite for destruction Sadly, the gharial is in serious trouble. Breeding populations survive in only four locations on the Ganges river system – three in India and one in Nepal. It’s already considered extinct in Pakistan, Bhutan, Bangladesh and Burma. The trouble is that gharials are riverdwellers and feed almost exclusively on fish. Other species of croc prefer the still waters of ponds or lakes, where they eat a varied diet, including mammals, birds and carrion. The gharial’s narrow choice of habitat and diet has largely contributed to its downfall. As humans dam the rivers, populations are isolated as movements are restricted. After the last Ice Age the gharial staked out about 20,000km 2 (7722 square miles) of rivers stretching from Pakistan to Burma. Today, its domain is just 200km 2 (77 square miles), and dwindling rapidly. Fishing is another worry. In supposedly protected areas, we have seen several gharials with snouts entangled in nylon gillnets at night. Though the crocs don’t E
A hatchling starts out towards the Girwa river, Katerniaghat Wildlife Sanctuary
The hatchlings make their first foray to the river
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E and buzz-snorted, we could see vapour streaming from his nostrils. Winter air temperatures range between 1oC and 20oC (34-68oF) so crocs usually bask on the sandbanks to warm up, but this male spent most of his time in the water, attending to his females, yet alert to any rival that might try to usurp his position. Fights between male gharials involve the most terrific displays of prowess. The territory holder surges forward, churning the water to a froth with his tail. If the intruder remains unintimidated, the two opponents engage in combat. Their slender snouts clash like swords in the air, though they seem too fragile for such violent action – indeed, you can often hear the crack of a tooth splintering or bone hitting bone. Eventually, one gharial will prevail and the other retreat, leaving the victor to claim his harem of eight to 10 females. The testosterone that fuels the males’ battles during January and February ebbs after mating and the females take their turn, fighting over the best sandbank nestsites. Once the territory squabbles are over, a mother gharial digs a nest hole with her hind feet and lays about 50 eggs directly into it. She covers it with sand, hiding her tracks from predators – hyenas, jackals and mongooses all enjoy gharial eggs. Then she returns to the river to keep watch from a distance through March and April until the eggs hatch in June or July. Many crocodilians are attentive parents, but little was known about how gharials care for their young until we began studying our captive population at the Madras Crocodile Bank. This is one of only five locations in the world that has successfully captive-bred gharials, and since 1982 it has produced hundreds of hatchlings. Observing them one day, I noticed a mother digging up her nest. I could hear her babies calling from beneath the sand, just as other species of young crocs do. With other species of crocodiles it can take a mother hours to help her babies to the water, as she cannot see exactly where they are. Her snout is so long that when she turns sideways to pick them up she loses sight of them, so she has to remember where each baby was and find it by feel. She often mistakes rocks, eggshells, clods of dirt and even baby turtles for her own young, and will tenderly carry them to the river. However, unlike other crocodilians,
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next of kin Crocodylinae family
CROCODILE
Although closely related, gharials are a different beast to their close reptilian cousins
romulus whitaker, skullsunlimited.com, NAture PL.com. Illustration by sheu-kuie ho
Crocodilians have been widespread since the Cretaceous period (about 144 to 65 million years ago). Alligators, crocodiles and gharials are each members of different families of crocodilian but share certain features. For instance, all have tiny receptors in their skin. These ‘integumentary sense organs’ (ISOs) or ‘dermal pressure receptors’ (DPRs) detect changes in the water around them and help them hunt for prey in dark and murky conditions. Alligators have them just on their head and jaws, while crocs and gharials have them all over the body. But, along with these similarities, there are also key differences, as the reptiles have evolved to cope with different conditions.
JAWS Longer, more V-shaped snout, yet still much broader and stronger than gharials’. More generalised and suitable for wide variety of prey TEETH 64-68 teeth interlock and remain visible when jaws close. Fourth tooth juts up behind the nostril
Alligatorinae family
Alligator JAWS U-shaped, rounded snout, significantly broader than that of a crocodile. Strong enough to crack turtle shells. Can exert pressure of 2000lb per square inch TEETH 70-80 sharp conical teeth. Lower teeth fit into sockets in the upper jaw, so are hidden when mouth is closed
E drown, their jaws are held shut by the nets so they starve to death. In other locations, dam construction and sand mining disturb nesting gharials, while local people raid their nests for eggs to eat. The Indian government, with help from the UN, set up Project Crocodile in 1974. We carried out surveys, behavioural studies and captive breeding projects. We reared thousands of youngsters, releasing them into protected areas. But few of these pioneers survived, and for a long time we didn’t know why. For example, one of our release spots, the beautiful Satkosia Gorge in Orissa,
Conservationists release young gharials into a protected area
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Only two of the 700 gharials released in the past three decades have survived to adulthood
Nature
Conservation
FACTSHEET
JAWS Slim and quick to reduce drag in the water, allowing for a whip-like action used to snap up fish TEETH 106-110 razor-sharp, slender, interlocking teeth
appears to have everything a gharial could want – fish, sandbanks, protection – and threats such as bamboo rafting and net fishing have been eliminated. Yet only two of the 700 gharials released here in the past three decades have survived to adulthood. It wasn’t until 1998, when I visited the Satkosia Gorge during the monsoon in mid-July, that I found out why. The river’s small streams had become torrents, and the river roared up to nine metres (30 feet) above its dry season mark, eroding the banks and uprooting trees. The released gharials were being flushed down river, out of the protected area and even into the sea. One was seen on a beach, others were found in mangroves and ponds. Those that took refuge in tributaries were caught in fishing nets. Project Crocodile was closed in 1992 but conservation and reintroduction efforts by the Indian government and the international community continue. Over the last 30 years, more than 12,000 eggs have been collected and over 5000 gharials released. The latest figures show that there are about 1500 gharials in the wild,
Herpetologist Romulus Whitaker first came to the rescue of India’s crocodiles – including the gharial – in 1970. He conducted some of the first surveys in the subcontinent and was a key partner of Project Crocodile. His partner, Janaki Lenin, has been chronicling the species’ changing fortunes for several years.
Latin name: Gavialis gangeticus Common name: Gharial (also known as gavial) Length: Hatchling up to 39cm (15in); adult female up to 5m (16ft); adult male up to 6m (20ft) Weight: Hatchling 95-125g (3-4oz); adult female 500kg (1100lb); adult male 1000kg (2200lb) Diet: Fish and crustaceans; juveniles also eat frogs and insects Breeding: Each male has a harem of eight to 10 females. Males display, court and mate in January/February; females nest in March/April; young hatch in June/July Habitat: Rivers Distribution: Breeding populations survive in four locations on the Ganges River system – three in India, one in Nepal (see map below) Longevity: Unknown. Late maturity suggests a comparatively long lifespan Conservation status: Critically endangered
GHARIAL HOTSPOTS The majority of surviving gharials live in just four areas
find out more E www.madrascrocodilebank.org The Madras Crocodile Bank is a trust founded by Romulus Whitaker, to protect and conserve India’s three native species of crocodile, including the gharial
PAKISTAN
NEPAL
Katerniaghat Sanctuary
E www.gharials.org Home page of the Gharials Conservation Alliance, an international organisation formed of individuals dedicated to saving the gharial E www.ircf.org The International Reptile Conservation Foundation, which supports conservation and research programmes to protect reptiles and their habitats
New Delhi
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Gharial
Gavialis gangeticus
Ch am
Gavialinae family
including fewer than 200 breeding adults, and about 800 in captivity. But although the species’ slide towards extinction has been slowed, our work has not yet saved it. In 2007, the International Union for the Conservation of Nature moved the gharial from the ‘Endangered’ to the ‘Critically Endangered’ category of its Red List. During the winter of 200708, a mysterious illness swept through the population of the Chambal river, just where our rehabilitation programme had been most successful, killing more than 100 individuals. Veterinary postmortem examinations revealed they’d died from kidney failure and gout. Investigations are still ongoing, but we suspect some kind of environmental toxin. The gharial continues to face an uncertain future, with its survival closely linked with the needs of the humans also dependent on the rivers. The threats from development, pollution and climate change increase day by day. But we and others continue to try to save it, along with much larger initiatives in place to protect the waterways so fundamental to its survival. And we are guardedly optimistic that awareness is being raised and that people are at last ready to do what it takes to save this most remarkable of crocodiles.
Ganges
Royal Chitwan National Park
INDIA
Son River Santuary National Chambal Sanctuary
getty, dreamstime
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Dinosaurs conquered the World April 2013
dinosaurs
History
The dinosaurs’ rise to dominance was once thought to be driven by brute force. But, says Dr Darren Naish, that’s far from the truth
Dinosaurs beat the competition, but it almost didn’t happen…
History
dinosaurs
he mesozoic era – the vast span of time that extended from 250 to 65 million years ago – is famously described as the ‘Age Of Dinosaurs’. It was once thought that these mighty reptiles were able to rule the planet due to sheer brute force alone, but a discovery made 50 years ago of the earliest large dinosaur known, called Herrerasaurus, would turn this idea on its head. Subsequent fossil finds in recent years have added weight to the argument that the dinosaurs didn’t out-muscle rivals to become the dominant force. Indeed, it now seems that their success was nothing more than a fluke. Discovering how the dinosaur age got started has never been an easy task. Species from the Triassic period at the dawn of the Mesozoic have been known since the 1800s. But the creatures discovered, including the bipedal predator Coelophysis and the omnivorous, long-necked Plateosaurus, are mostly from the latest part of the Late Triassic – they are about 210 million years old. These animals are fairly large, 3m long or more, with sophisticated skulls that show that they are relatively advanced members of the dinosaur family tree. The lack of older, more primitive, dinosaurs long made it difficult to understand what happened during the earliest stages of their evolution.
CORBIS, Nobumichi Tamura x2, getty, smokeybjb/wiki
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It was the discovery of Herrerasaurus in 1963 that gave us a window into some of the earliest years of the dinosaurs. A team led by Argentine palaeontologist Dr Osvaldo Reig studied the remains of a surprisingly old dinosaur at Ischigualasto in northwestern Argentina. Reig named the animal Herrerasaurus after local farmer Victorino Herrera, who first spotted the fossils. These remains are from the earliest part of the Late Triassic, and hence are about 230 million years old. Reig knew Herrerasaurus was a predator of some sort, but the remains were not good enough for him to reconstruct the animal’s appearance and lifestyle confidently. Far better specimens were discovered in 1988, when Dr Paul Sereno at the University of Chicago and colleagues searched anew at the same spot. Thanks to these finds, we now know Herrerasaurus was bipedal, with a narrow snout, long, ‘re-curved’ teeth that curve back
“It’s become clear that the earliest, timid, dinosaurs did not go through a rapid evolution”
Palaeontologist Dr Paul Sereno holds a skull of Herrerasaurus found in Patagonia
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making it hard for prey to escape, and large raking claws on the inner three fingers of its five-fingered hands. It was large, reaching 4.5m – roughly the length of a large car – and weighing perhaps 200kg. To date, Herrerasaurus remains the oldest large dinosaur we know of. Compared to dinosaurs from the Jurassic and Cretaceous, the two later periods within the Mesozoic, 4.5m is not large at all. But compared to other dinosaurs from the early part of the Late Triassic, it was a giant. In 1991, Sereno and colleagues discovered another Ischigualasto dinosaur, later dubbed Eoraptor. It seems to have been a far more typical Triassic dinosaur, and indeed a variety of similar-aged species are now known. All are lightly built and less than 2m long. Most must have been omnivores, foraging in the undergrowth and mostly keeping out of sight. The timid species discovered belong to different branches of the dinosaur family tree, so we can be sure that being small and inconspicuous was the lifestyle adopted by most early dinosaurs. Three’s a crowd These early dinosaurs were far from alone in the Triassic world. Dinosaurs are part of a major group of reptiles termed archosaurs. Early in the Triassic, archosaurs diverged into one lineage that led to dinosaurs and later to birds, and another that led to crocodiles and their kin. These are respectively termed ‘bird-line’ and ‘croc-line’ archosaurs. Some of the croc-line archosaurs that lived in the Triassic were top predators. At more than 5m long, they were able to attack and defeat an animal like Herrerasaurus. In fact, many croc-line archosaurs evolved body shapes and lifestyles that mimicked those of the dinosaurs that would emerge more than 50 million years later. Meanwhile, the ancestors of mammals – the synapsids – included small, furry, mammal-like forms as well as tusked, pig-sized herbivores and badger- and rat-sized omnivores and predators. For much of the 20th
dinosaurs
History
The dinosaur vs… Traditionally considered the dominant force in the Mesozoic, dinosaurs weren’t the biggest, or fiercest, prehistoric heavyweights
Eoraptor (DINOSAUR) Size: 1m long Diet: Leaves, buds and small animals Attack and defence: Mostly relied on speed to escape danger
Eoraptor was a typical early dinosaur. Like the dinosauromorphs that were its close relatives, it was a small, slender, long-legged omnivore that would have been in danger of being eaten by big, predatory croc-line archosaurs. Short forelimbs show that Eoraptor was bipedal. It had five slender digits on each ‘hand’ with curved claws on the end of three of them. These claws could have been used in fighting as well as manipulating plants during foraging. Its jaws contained both leafshaped teeth as well as re-curved fangs.
Silesaurus
Saurosuchus
Poposaurus
Size: 2.3m long Diet: Leaves, buds, small animals Attack and defence: Weak bite – mostly relied on running from danger
Size: 7m long Diet: Smaller croc-line archosaurs, dinosaurs, dinosauromorphs Attack and defence: Slashing bites taken with huge fangs and powerful jaws
Size: 4m long Diet: Smaller reptiles, including dinosauromorphs Attack and defence: Slashing bites, long fangs, ability to rear up on hind legs
Saurosuchus was one of the largest and most terrifying of the rauisuchians, a group of predatory croc-line archosaurs. Quadrupedal, erect-limbed and probably fast and agile for its size, it would have been an arch-predator, capable of killing most animals of the time, including dinosaurs like Herrerasaurus. Its skull was deep but narrow, with long, curved, serrated teeth lining the jaws. Armour plates protected the top of its neck, back and tail.
Poposaurus looked like a large predatory dinosaur, but was actually a bipedal croc-line archosaur. Poposaurus was a long-tailed, longlegged predator with short forelimbs. It was presumably a swift bipedal runner that used a deep upper jaw and long, re-curved teeth to inflict fatal damage to prey. It is one of several croc-line archosaurs that show how members of this group independently evolved the sort of body shapes seen later in dinosaurs.
(DiNOSAUR0MORPH)
Silesaurus and related dinosauromorphs were slender, long-limbed quadrupeds that would have avoided the attentions of both predatory croc-line archosaurs and early predatory dinosaurs. A small head and teeth suited for cropping leaves suggest that these animals ran away from danger. Dinosauromorphs similar to Silesaurus gave rise to dinosaurs some time during the Middle Triassic. Fossils, first described in December 2012, appear to be from the earliest-known dinosaur, Nyasasaurus parringtoni, which dates from this era.
6
(Croc-line archosaur)
per cent of terrestrial animals were dinosaurs before the extinction events of the Late Triassic
30
(Croc-line archosaur)
million years is the length of time that early dinosaurs remained small and inconspicuous
Exaeretodon (synapsid)
Size: 1.8m long Diet: Leaves and stems of tough plants Attack and defence: Powerful bite with fangs and broad, shearing teeth. Hides in burrows. Exaeretodon represents the synapsids, the hot-blooded, often furry Triassic ancestors of mammals. A short-legged, tubby-bodied animal, Exaeretodon used its shearing cheek teeth and powerfully muscled, broad jaws to slice up tough plant material. Curved, fang-like teeth at the front of the mouth could have been used in fighting. These animals were not speedy runners and probably dug burrows for shelter and to run to in a hurry to escape the clutches of larger, predatory animals.
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teeth were present in the jaws of the Triassic predatory dinosaur Herrerasaurus
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…the rivals
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History
dinosaurs
What if…
Dinosaurs (top right) have come out on top, despite competition from croc-line archosaurs (top left) and early mammals (bottom right)
science photo library, superstock
…the dinosaurs’ competitors survived? The latest evidence shows that the dinosaurs owe their rise to world domination to two extinction events at the end of the Triassic period. But what if these extinction events never occurred? For starters, it’s likely that the croc-line archosaurs would have persisted as top predators. Ironically, this means that the appearance of amphibious, freshwater crocodiles and alligators would have been prevented. The persistence of their ancestors would have left no ecological niches to fill in swamps and rivers. Dinosaurs and other bird-line archosaurs would have continued to live in the background and would have remained small. The dominance of the croc-line archosaurs would have left few ecological niches for the dinosaurs to exploit, so many of the species we know to have existed would not have developed. Interestingly, this means that birds would not have appeared, since their origin was contingent on the diversification and success of predatory dinosaurs. What about mammals? As in the real world, we can be confident that small burrowers,
swimmers and climbers would have evolved during the Mesozoic, and would mostly have tried to avoid the attentions of croc-line archosaurs. The evolution of large mammals with unusual body shapes – whales, antelopes and humans, for example – would have depended on the asteroid that killed off the dinosaurs 65 million years ago killing off croc-line archosaurs. However, if we imagine that this extinction event at the end of the Cretaceous did finally knock the
croc-line archosaurs out of the game, mammals would now have to contend with small-bodied dinosaurs. It’s likely the dinosaurs – still small and inconspicuous – would have lived through the asteroid strike. The mammals and dinosaurs would have raced to evolve a large size, and there are no obvious indications that one would succeed above the other. Perhaps, our modern world would have been jointly ruled by big mammals and big dinosaurs.
Century, it was believed that dinosaurs were competitively superior to croc-line archosaurs and synapsids. It was thought that members of these groups literally tussled for dominance on the Triassic plains and with their long, erect legs, clawed hands and sprightly abilities, the dinosaurs were able to win the evolutionary arms race. Croc-line archosaurs would, so it was supposed, have had to abandon their claim on the land and eke out a living forever afterwards as marsh- and lake-dwelling crocodiles and alligators.
But new discoveries have painted a more complex picture. Claims that dinosaurs were special relative to other archosaurs and to synapsids no longer ring true. The earliest, timid dinosaurs did not go through a rapid evolution that would turn them into fighting machines. Since 2003, there has been a burst of discoveries of dinosauromorph fossils – dinosauromorphs being the creatures that gave rise to the dinosaurs and lived alongside them for millions of years in the Triassic. These new fossils have shown that
dinosaurs were not especially different from the dinosauromorphs. So the dinosaurs emerged quietly, without any dramatic increase in body size or important shift in lifestyle or ecology from among this group of small predators or omnivores. Looked at objectively, there is nothing in the fossil record that makes the success of dinosaurs look at all inevitable. In fact, it was a world that belonged to croc-line archosaurs. So, what happened? How did dinosaurs go from being small, furtive animals of the background to a dominant global force?
rise of the dinosaurs
The timeline of the Mesozoic era is littered with species vying for supremacy
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EARLY TRIASSIC (252-247Ma)
MIDDLE TRIASSIC (247-235Ma)
250Ma Ma = millions of years ago
240Ma
Bird-line archosaurs and croc-line archosaurs diverge from one another
Emergence of the first true dinosaurs, such as Nyasasaurus
dinosaurs
The strongest evidence appears to show that two mass extinction events – both occurring during the last part of the Triassic – removed large-bodied synapsids and croc-line archosaurs from the equation, leaving dinosaurs to rule the world. The first of these extinctions happened about 220 million years ago. Many largerbodied synapsids died off at this time, as did various non-dinosaurian reptile groups and numerous marine species. A climatic change, perhaps triggered by the splitting of the Pangaean supercontinent – the huge landmass that incorporated all the continents we now see – caused aridity in many areas. It has been suggested that the resultant change in vegetation and rainfall initiated a cascade of ecological consequences. The second mass extinction event happened at the very end of the Triassic, 200 million years ago. It seems to have caused major, rapid changes to the global flora and fauna. The impact of an asteroid is a likely cause of this event, just as it is for the extinction event of 65 million years ago that wiped out the dinosaurs themselves (except for the birds, the lineage of dinosaurs that survived). There is even a potential ‘smoking gun’ for this Triassic strike: the enormous Manicouagan Crater in Quebec. Representing the impact site of an object perhaps 5km (3 miles) across, it is presumably big enough to have caused major perturbations in the global ecosystem. Similar-aged craters in western Canada, France, the Ukraine and North Dakota have been suggested as evidence for a series of impact events. The Manicouagan Crater means it might have been formed as much as 214 million years ago. But several pieces of evidence in recent years, including a burst in fern growth, have provided support for another impact happening at 200 million years ago. It’s known that when other plant species
“How did dinosaurs go from being small, furtive animals of the background to a dominant force?”
History
archosaurs were presumably more adversely affected by the extinction events than the mostly small, ecologically generalised dinosaurs. The general pattern of the fossil record shows croc-line archosaurs doing okay prior to the event, but are all but absent after it. The dominance of dinosaurs, then, appears to owe itself to the fact that many of their competitors simply disappeared. Had those extinctions not occurred,
The Manicouagan Crater in Quebec is thought to have been caused by a 5km-wide asteroid at the end of the Late Triassic
are wiped out, ferns enjoy a huge growth in population. Less controversial is the massive volcanism that occurred at the same time in the northern part of Pangaea. It appears to have caused global warming and ecosystem collapse. Ruling the roost After these events, dinosaurs flourished – the fact that they made 50 per cent of the tracks we now see from this time is evidence for this. Furthermore, the size of the track-makers doubles during the same period. As big animals that were living out in the open and sitting at the top of their respective food pyramids, croc-line
the Mesozoic could have been the age of the crocodile rather than the dinosaur. Fifty years on from the discovery of Herrerasaurus, we know that the dinosaurs weren’t as formidable a force early on as was once thought – they were fortunate survivors. Dr Darren Naish is a palaeontologist at the University of Southampton and the author of Great Dinosaur Discoveries.
find out more E Watch Walking With Dinosaurs videos on Earth Unplugged, a new YouTube channel at www.youtube. com/user/EarthUnpluggedTV
MESOZOIC ERA (250-65Ma) LATE TRIASSIC (235-201Ma) 230Ma
210Ma
Synapsids decline Croc-line archosaurs Earliest mammals after mass at an all-time high in appear, such as Megazostrodon extinction event terms of diversity
200Ma EXTINCTION EVENT
EXTINCTION EVENT
Eoraptor and Herrerasaurus are now roaming Earth
220Ma
JURASSIC (201-145Ma)
Dinosaurs diversify and increase in body size
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An excerpt from A book you should read
Nature
inside the pages
Tigers My Life Ranthambhore and Beyond By Valmik Thapar In his 35 years of engagement with the Ranthambhore tigers, Thapar remembers Genghis ‘the thinking tiger’ amongst others in an excerpt tiger of Ranthambhore. A typical day spent with him comes from my records of March 1984, ‘Genghis moves into this patch of long grass at about 11.30 am after consuming the remains of a wild boar piglet that he had killed the previous evening. He sleeps in the shade of the grass till 2.30 pm, when a group of sambar appears on the shore, slowly moving towards him. As they get close, he erupts into a charge, chasing past us and slamming his forepaws into the earth. He screeches to a halt in front of our jeep. He snarls at us, annoyed, but it has been an amazing display of breathtaking power, strength, and speed. Later, he quietly crosses to Malik Talao, and stands motionless in the tall grass, watching sambar wade through the waters of the lake. His eyes settle on a target and he races out through the grass, scattering the deer in all directions. Some end up in deeper April 2013
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was certain that the 1980s would be the most amazing decade in the life of the tiger. It was in 1983 that we encountered the great feeding behaviour between adult tigers near Malik Talao, where for the first time I witnessed real aggression as two tigers tugged at both sides of a carcass in their effort to own it, and the forest reverberated with the roars of tigers, stunning my senses like never before. This was the beginning of Noon’s reign around the lake and over the next decade, she became one of my favourite animals. It was at the beginning of her regin in late 1983 that we encountered the remarkable male tiger, whom we ended up calling Genghis. He exploded across the Ranthambhore lakes, and his activities during the one season he was around were legendary. He was unique, and I spent a lot of time with him, predicting his every move. To me, he was the great thinking
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An excerpt from A book you should read
E
water where their movements are hampered in the panic of the moment. There is complete chaos, but Genghis has found a target – a young sambar doe floundering in the water. He crashes through the water amidst sheets of spray cutting towards his quarry – his speed is astonishing. The mother of the doe turns around but it is too late. The tiger’s strides have brought it to the deer and his paw smashes down on the helpless deer, forcing it underwater for some seconds. Only his tail is visible but he soon surfaces with his trophy. The sambar mother watches the death of her fawn in distress. Genghis wades ashore, carrying the deer in his mouth and into the long grass to feed.’ Tigers
Genghis wades ashore, carrying the deer in his mouth and into the long grass to feed.’ Tigers were rewriting their natural history and this was the first time ever that such a sight was recorded from them. He was a temperamental tiger and never permitted you to watch him feed. If you got too close, he would mock charge, frightening you out of your wits. Noon was the resident tigress and she learnt this water-based activity from Genghis. Her charges on sambar in the water were also spectacular. There were lots of large males in the area. Broken Tooth ruled the Kachida valley and was an expert at snatching the kills of females in his area. When
gunter zeisler
In my 35 years of tiger-watching, this was the only tiger that chased like a cheetah
were rewriting their natural history and this was the first time ever that such a sight was recorded. Tejbir filmed it and so did a National Geographic unit. The rarity of the event was applauded by the world and Genghis did more to attract people to the shores of Ranthambhore than any other tiger. This water-based activity brought him into regular contact with the crocodiles of the lake, and Genghis had few problems – he could always scavenge 80
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Genghis vanished by the monsoon of 1984, he was replaced by Kubali on the lakes, not to forget the big Bakaula male and the Nalghati male. And then there was that remarkable tigress called Nasty, who would charge the jeep at a moment’s notice. She must have charged me at least 20 times, and always created panic. But these were mock charges and looked fiercer than they actually were. The mid - 1980s were some of the
finest years of tiger - watching that we were had. Fateh lived on the roof of the gate in Jogi Mahal and this was our home – our listening post. At the sound of an alarm call, we would rush into a jeep and take off. Even while we would be sitting at Jogi Mahal, tigers would slip in and out at night. One night, while were were waiting for dinner to arrive, a tigress passed us with 3 cubs towards the kitchen from where our dinner was coming laden in trays. What chaos ensued as the cook saw the tigers and the dishes flew all over the place, while tigers ran off! Jogi Mahal was our watchtower and centre of operations. Moonlit nights, roaring fires, excellent company, and music made it memorable. Every day was different and the spirit of freedom enveloped us. For me, the 1980s was an era difficult to describe, and for those who did not witness it, difficult to imagine. It was on a day in 1985 that I saw 16 different tigers in one day. Nobody believes me today when I say so but the photo-records of this period reflect the density of tigers in Ranthambhore. There were nearly 40 tigers in 60 per cent of the total area of 400 sq kms in the park. It was also during this year that Fateh, for the first time in 17 years, recorded the mating of tigers in Ranthambhore – involving Kubali and Noon around the lakes. Who would have believed in 1976 that we would see this across the lakes! A dream come true! It was also my first study of the family life of tigers and by 1986, I was following three tigresses and their cubs, and subsequently, I produced what was my favourite book, The Secret Life of Tigers. It was all written in the peace of Jogi Mahal, as each day we watched the tiger’s natural history unfold. Extracted with permission from Valmik Thapar from Tigers - My Life Ranthambhore and Beyond by Valmik Thapar (Oxford University Press 2011).
Edu Talk Naveen Chopra, chairman of The Chopras, an overseas education consultancy firm, stresses on the importance of addressing the holistic needs of the students
“Think things through. Get advice from the right kind of people, at the right time and of the right kind” emerging technologies, robotics and satellite technology.
What is the vision for The Chopras? Our mission statement is shaping life and careers through education. We want to promote excellence through quality educational services. What made you realise the need for an organised education consultancy services for students who wish to study abroad? In the early ‘90s there was a global recession and Australia, where I was residing, also spun into the recession. I noticed the number of people who came to us for work were from India. I dug further and found that the schools in India had no faculty or community centres that could council local students. So then we pitched our idea and started the company in ’95. I went on a talk rampage in schools and colleges speaking on the importance of career planning and how and what the basics of career planning are. How is your organisation different from the other education consultancy services? We always try to address the holistic needs of the student. And it starts from the very basics of a student’s dream, personality, strength and weaknesses, their personal likes and dislikes, family background and expectation, to their aspiration, to what they want to do. There have been so many instances where students are inclined towards a particular field, say animation but their parents would discourage them, thinking it as a poor option. Today, Hollywood is outsourcing many of their projects to India because we have the talent for animation and multimedia. Our thing is to always try and anticipate the needs of the students on the basis of changes in the market place, changes in technology. With an increase in good universities and institutions in India, do you see a decline in the number of students who want to study abroad? There is no substantial decrease and I will tell you why. Students who opt to go overseas are categorised into various
How do you view the students of this generation? When we started, 90-95 per cent of students didn’t have a clue as to what they wanted to do with their lives and now, 60-70 per cent of the students have a fair idea, which means they are pretty clear about what they want to do, which is very healthy and I love that. I think students today are better informed but also can be opinionated.
economic segments. You have the elite group for whom spending of ` 13 lakhs on a child’s education is not much of a big thing. Then you have the affluent class who send their children overseas for two reasons: first as an exposure to experience how the rest of the world lives and second because the child hasn’t scored the requisite 97 per cent to secure an admission in a university in the country. Then, comes the upper middle class, where the child will be sent abroad for further study and will be expected to work overseas for exposure and maybe look at migration opportunities to settle down. Within this bracket, also comes the middle class; wherein the family income is ` 12-15 lakhs and where migration also acts as a factor. Now if there is a recession, when job opportunities abroad vanish, this segment shrinks. Then you have the grey segment, which has always given us a bad name. Students largely from Punjab, Andhra Pradesh who want to go to abroad and work full time on a student visa. What courses are popular amongst students? By far, it is the MBA; business and management courses. A trend that is changing is towards courses in bio-science and media communications along with
What is the one fundamental advice you offer? Think things through. Get advice from the right kind of people, at the right time and of the right kind. I would say to students instead of focusing on rankings, I would say ask what it is that makes a good institution – you should have a good teaching staff, if the subject taught is interesting enough and then the content of your course you would want to study because that is the knowledge that you are going to gain, which will determine which profession you will enter into. Your views on the educational policies in the country? In my view, they are not quite in sync. You need money to run institutions and that money has to come from somewhere. If a student is from a family who can afford to pay ` 3 lakhs a year, then why is he charged only ` 300? This is where social responsibility kicks in. Reservations are causing a lot of problems with the students. Reservation is fine, but the way it is being conducted is not. If you want to reserve seats, then you need to reserve it for people who deserve it. Some of these sets of people lag behind when it comes to the required level of education. And instead of passing them in the programme, we can have then undergo a six month course, which brings them on par with their contemporaries. April 2013
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In a nutshell
What is evolution? During the 18th century, naturalists began attempts to classify living organisms on a scientific basis. The similarities and differences that emerged prompted attempts to understand their origins, culminating in 1859 with the publication of On The Origin of Species by the English naturalist Charles Darwin. He proposed that evolution is the result of the natural selection of organisms which have traits making them better able to survive and pass those traits on to their offspring. Darwin could not say exactly how traits were transmitted, as genes weren’t discovered until after his death. However, it is now known that the combination of changes, or ‘mutations’, in the genetic chemical DNA, and natural selection, underpins evolution. Many examples of evolution at work have since been identified.
The Big Idea exploring life’s great mysteries
Robert Matthews investigates
Evolution
It explained how complex life can arise from the simplest of beginnings. Yet Darwin’s theory of evolution by ‘natural selection’ also kicked off a 150-year row between science and the church... Both eyes on one side of the body? Evolution says why
E
It’s the latest twist in the often bitter controversy that has surrounded the theory of evolution for the last 200 years. Like Darwin’s theory, it has its origins in one of the most seemingly humdrum of all scientific endeavours: classification. The idea of creating a catalogue of all living things dates back to at least the Ancient Greeks, but the first serious scientific effort was begun around 350 years ago by an English naturalist. John Ray wanted to show the similarities and differences between God’s creatures, for these were what he believed them to be – a belief bolstered by what he saw as the miraculous way in which creatures were so well-suited to their environment. By 1704 Ray had produced a threevolume encyclopaedia cataloguing almost 19,000 plant species. Ironically, in the process he also provided the means to E undermine the biblical account of April 2013
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t first glance, the humble flatfish looks like it’s been designed by someone with next to no artistic talent. Why else would its two eyes be stuck on one side of its body, like some kind of afterthought? Yet their seemingly odd positioning serves the flatfish very well, allowing it to spot prey swimming above it while it remains concealed on a sandy sea floor. That comes as no surprise to scientists, who regard the flatfish as living proof of the power of evolution. The end result may not look very elegant, but it’s the result of the twin drivers of evolution: random genetic mutations, which cause changes in the traits of all living creatures, plus natural selection, which promotes those mutations that boost the chances of organisms surviving to reproduce. Yet according to some, this scientific explanation simply must be wrong. They are creationists, and they insist that the flatfish – like every other creature on Earth – is the direct result of divine intervention, its characteristics specified by an omnipotent Creator perhaps as recently as around 6000 years ago. Now studies of fossilised relatives of the odd-looking flatfish are adding fresh fuel to the long-running argument between scientists and creationists. And according to scientists, they back up the arguments put forward 150 years ago by the English naturalist Charles Darwin that evolution alone is perfectly able to create the diversity of living creatures that we see today.
A
Our system for naming species is older than Darwin’s theory for their evolution Classification
Order of nature The theory of evolution owes a huge debt to the efforts of biologists to classify the myriad forms of life on our planet. The most famous classification system was devised by the Swedish botanist Carl Linnaeus (1707-1778). It arranges all living things in a hierarchical system, with organisms being categorised first according to their kingdom (of which there are five, including animals, plants and fungi), then phylum, class, order, family, genus and species – the last two being used to give each organism a unique identifier, such as Homo sapiens in the case of modern humans. Modifications have been suggested to the original system, such as the introduction of overarching ‘domains’ based on genetic considerations, but the Linnaean system has remained largely intact to this day.
TIMELINE The evolution of a theory
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E creation, by revealing hints that more complex life-forms developed from simpler ones, rather than all being created at the same time. That evidence began to mount following the publication in 1753 of the first part of a major new catalogue of life by the Swedish botanist Carl Linnaeus. His catalogue was based on what has become the most celebrated method of classifying organisms, which began by allocating them to one of several huge kingdoms, then refining the definition down to genus, and then individual species. The F Linnaean system revealed a kind of ‘tree of life’ of ever greater refinement, with sophisticated plants and animals apparently developing from simpler ones. This was not an idea that appealed to Linnaeus – as the son of a clergyman, he believed God created all species individually. But later naturalists had fewer qualms about challenging orthodoxy, among them the French academic Jean Lamarck. In the early 1800s he set about tidying up Linnaeus’s work on invertebrates and highlighted the apparent ‘evolution’ of creatures towards evergreater sophistication. He even put forward an explanation of why it happened. According to Lamarck, creatures acquire characteristics during their lives that make them better able to survive, and pass them on to their offspring, who then also do better than their competitors. Lamarck offered the example of the giraffe, which he argued was simply a type of antelope which had steadily acquired a longer neck through stretching to pick leaves off trees. Lamarck’s idea of inheritance of acquired characteristics was a pioneering
attempt at a scientific theory of evolution. Critics pointed out, however, that there was no evidence that creatures could inherit traits acquired during their parents’ lifetimes: as they put it, blacksmiths’ sons are not born with bulging biceps. Even so, Lamarck’s attempt intrigued many thinkers, including a Cambridgeeducated naturalist in his early 20s named Charles Darwin. After a five-year voyage to South America and beyond aboard HMS Beagle, Darwin returned home to ponder the evidence he had found for species changing to suit their environment. Giant ostriches in the Argentinian pampas seemed to give way to smaller ones in Patagonia, while on the Galapagos Islands Darwin found finches apparently descended from those on the mainland, but with beaks better suited to eating the food found on the islands. Adapt and survive The breakthrough came in autumn 1838 when Darwin read Thomas Malthus’s famous 1798 book Essay on the Principle of Population. It claimed that mankind can expect to be locked in a perpetual struggle for resources in which only the strongest will survive. Darwin realised that the same argument applied to other life-forms as well – and that the struggle for existence could be a ‘filter’ through which only some creatures would pass: specifically, those which possessed the attributes needed to survive. As conditions changed, so would the need for different attributes – which, from discussions with animal breeders, Darwin knew could arise completely by chance. The result of this combination
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H Englishman John Ray publishes the first attempt to catalogue living organisms, revealing what he believes are the God-given similarities and differences between what he called ‘species’.
Swedish botanist Carl Linnaeus begins publication of his attempt to bring order to the variety of life on Earth via his classification system. It hints at evolution from simple to complex organisms.
H Thomas Malthus publishes his famous ‘Essay on Population’, showing how resources are outstripped by increasing numbers of people, leading to the concept of survival of the fittest.
Publication by the French naturalist Jean Lamarck of his theory of the development of life on Earth, which suggests organisms pass on beneficial traits they acquire during their life.
E Publication of On The Origin of Species by Means of Natural Selection by Charles Darwin, which rapidly becomes a bestseller. Its thesis convinces many scientists – but attracts criticism from the Church.
The Big Idea exploring life’s great mysteries
Evolution or creation?
Darwin vs God
The apple, Malus domestica, evolved from wild fruit native to Kazakhstan
of random changes and natural selection would be the emergence of new species. Despite having the basis of his theory, Darwin didn’t publish it until 1858, when it became clear that another naturalist, Alfred Russel Wallace, had reached similar conclusions. The two jointly published their findings in an academic journal, after
which Darwin wrote up his work for the public. In 1859 it emerged as one of the most famous books ever: On the Origin of Species by Means of Natural Selection, or the preservation of favoured races in the struggle for life. Although quickly accepted by scientists, Darwin’s thesis provoked outrage from the clergy, who were appalled by the G challenge to the Bible and its
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Austrian monk Gregor Mendel publishes results of garden experiments which identify the existence of the genes needed to transmit traits down the generations. The results are overlooked for decades.
H Evolution among bacteria exposed to low doses of antibiotics creates drugresistant strains, such as the superbug MRSA, which become a major health issue threatening the lives of millions of patients worldwide.
Identification by Matt Friedman of the University of Chicago of new types of fossilised flatfish, which become the latest example of “missing links”, connecting ancient life-forms to their modern counterparts via evolutionary steps.
1944 G Oswald Avery and colleagues at the Rockefeller Institute in New York track down the identity of genes to an obscure chemical code-named DNA that’s found in the nucleus of virtually all living cells.
account of creation in the book of Genesis. While Darwin was confident his theory could withstand the criticisms of clergymen, he was all too aware of a scientific flaw at its core – the lack of any detailed explanation of how traits are passed down the generations. Unknown to Darwin, glimmerings of the solution had already been found by an obscure Austrian monk named Gregor Mendel. While breeding pea plants in his monastery garden, Mendel found that traits combined as if they came in ‘packets’ of inherited material. For example, crossbreeding tall and dwarf plants did not produce medium plants, but different proportions of tall and dwarf offspring. Mendel published his findings in an obscure journal, and it was not until 1900 – long after both he and Darwin were dead – that they were rediscovered and seen for what they were – evidence for the ‘packets’ of inheritance we now call genes. The precise nature of genes only became clear in the middle of the 20th century, following work by a team led by the American biochemist Oswald Avery and colleagues at what was then E the Rockefeller Institute, New York. April 2013
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Darwin’s theory of evolution has faced many challenges since its inception 150 years ago, particularly from those who say it goes against their religious beliefs. But the most sustained attacks on evolution have come from fundamentalist Christians in America. Around a century ago, the Seventh-day Adventist Church launched what has become the ‘creationist’ movement, which says all life was created by God in a matter of days, perhaps as recently as 4004 BC. Creationists have sought to undermine Darwinism by claiming that it simply cannot explain the wonders of life. This has led to the emergence of ‘Intelligent Design Theory’, according to which certain features of living creatures – such as the blood-clotting system of humans – are said to be far too unlikely to occur via the evolutionary processes of random mutation and natural selection, and thus must be explained as the result of ‘intelligent design’ by a supreme being. Darwinists concede there are gaps in the scientific explanation of such astonishingly sophisticated systems, but insist it does not imply the need for divine intervention.
The Big Idea exploring life’s great mysteries
E In 1944, they showed that bacteria inherited traits by passing on copies of a simple molecule in the nucleus of almost all living cells called deoxyribonucleic acid, or DNA. The identification of DNA as the carrier of inherited traits completed the scientific foundation of Darwin’s theory. Where he In 1860, a sharp-eyed described evolution somewhat vaguely German palaeontologist as “descent with modification”, scientists named Christian von could now sum it up as “genetic mutations Meyer spotted a plus environmental pressure”. delicately-patterned fossil But while the mechanism of evolution in limestone deposits may be clear, the evidence for its in southern Germany – and gave science one effectiveness remains a source of bitter of its most celebrated dispute. According to Darwin’s theory, examples of evolution in every living creature is the result of Christian von action. The fossil was of evolution from more ancient organisms. Meyer: fossil hunter a feather from a longThat means that the origins of every extinct creature roughly species should ultimately be traceable the size of a modern-day raven, whose through the fossil record back to the remains were found the following year, emergence of life itself, around 3700 and was duly named Archaeopteryx, million years ago. from the Greek for ‘ancient feather’. Yet that evidence is far from clear. The Supporters of evolution pointed out fossil record is patchy, with gaps between similarities different versions of some organisms The missing link between the spanning hundreds of millions of years. between birds creature and both Scientists point out that this is hardly and dinosaurs? birds and reptiles surprising since fossilisation only takes – for example, place under special conditions, and feathers arranged even when it succeeds in into wings, but preserving some long-dead a toothed creature, geological and jaw rather climatic upheaval can soon than a beak. destroy the evidence. This prompted English Fortunately, despite the odds, biologist Thomas Huxley, fossil-hunters have found many one of Darwin’s staunchest impressive examples of evolution supporters, to argue that working over millions of years. One Archaeopteryx was some form of the most spectacular emerged in of 150-million-year-old “missing a limestone quarry in Germany just link” between dinosaurs and months after publication of Darwin’s modern birds. However, confirmation On The Origin of Species in 1859. It linked of the status of Archaeopteryx has F birds and dinosaurs. Now scientists come only within the last 20 years or so, are hailing the discovery of another following painstaking analysis of the half impressive example: fossilised versions of dozen or so other specimens that have the modern flatfish. since been found. While the specimens Even in Darwin’s time, critics believed aren’t identical, they are similar enough these odd-looking fish posed a major to convince most researchers that challenge to his theory. Ordinary fish Archaeopteryx is the earliest-known clearly benefit from having an eye on example of a bird. each side of their bodies, and flatfish benefit from having both eyes on the th like a reptile same side. Yet if flatfish really have Feathers like a bird, tee evolved from ordinary fish as Darwin claimed, the fossil record should contain examples of fish with eye arrangements somewhere between the two extremes. But what possible
Fossil confirmation
Evolution in action
The world’s earliest birds
The peppered moth Evolution is not confined to the distant past, as shown by the peppered moth, Biston betularia. Before the Industrial Revolution swept England around 200 years ago, the most common variety had a light coloured, speckled appearance. But, by the end of the 19th century, it had been all but replaced by its black-coloured relative. In 1896, the English naturalist James Tutt suggested an explanation: the black variety was harder to spot by birds when resting on trees blackened by the pollution from heavy industry. In other words, the black variety was benefiting from Darwinian ‘natural selection’ linked to the chance mutation that gave them their darker coloration. Controlled experiments have since confirmed Tutt’s suspicion – making the peppered moth a celebrated example of modern evolution. The introduction of pollution controls in the 1950s has led to cleaner trees – and a resurgence in the original light-coloured moth.
evolutionary advantage could there be in such bizarre arrangements of eyes – and where were the fossil examples of it happening? Darwin insisted there must be some benefit in having eyes positioned between the two extremes, but struggled to say precisely what it might be. His biggest problem, however, was the absence from the fossil record of any examples of flatfish with eyes in the intermediate locations. Now some scientific detective work by an American graduate student has revealed that fossils found over a century ago are the long-sought missing link. Fish fingered Matt Friedman of the University of Chicago made the discovery in 2008 after looking through a textbook of fossil fish. Like the venerable works of Ray and Linnaeus, the book included classifications of each example. One type of fossil fish, the 50-million-year-old Amphistium, caught Friedman’s attention. The fossils had been classified as a different type of fish, since their skull shape wasn’t clear
Question Time Matt Friedman is a graduate student of the Field Museum and University of Chicago. He has made headlines with his discoveries about fossil flatfish, which add to the weight of evidence for the theory of evolution.
How did you come to work on the science of evolution? My interest in evolution stems from an early fascination with fossils. The museum near my childhood home in Cleveland, OH, displayed some remarkable specimens of primitive fishes collected from local rocks deposited about 360 million years ago in an ancient seaway. As I grew up, I discovered the questions they raised in my mind could be addressed with the tools of science.
What’s been the response of fellow scientists to your discovery?
deity is, by definition, capable of doing anything – including creating fossils that look like missing links. As such, creationism is the antithesis of science. It makes no predictions, and is utterly unaffected by new evidence, every fresh discovery being by definition consistent with creation by an omnipotent being. In contrast, evolution predicts the existence of missing links, and their emergence adds ever more weight to the theory. Some would say it makes an even grander claim than creationism too: that the processes of evolution are still working miracles with living things to this day. Robert Matthews is a science journalist and Visiting Reader in Science at Aston University, UK. www.robertmatthews.org
find out more E Evolution: a very short introduction by Brian and Deborah Charlesworth (Oxford University Press, 2003) E www.eol.org The Encyclopaedia of Life, an online project
What about the reaction of creationists? Creationists’ responses have come in a few predictable flavours: either the results are discounted out-of-hand as insignificant, or are said to be significant if true and then rejected as gross misinterpretations. These are the same tired arguments wheeled out in the face of every new discovery, and they highlight an important distinction: while scientific frameworks are revised in the face of new data, the static creationist agenda is immune to their implications.
How should scientists respond to creationism in schools? It’s crucial to actively promote the teaching of science at all educational levels, and vital when confronted with attempts to sneak creationism into classrooms. A working knowledge of the scientific method immediately exposes ideas like ‘intelligent design theory’ for what they are: scientific in name alone. April 2013
getty, spl, naturepl.com
– and nor was the location of their eyes. Friedman suspected the fossils might still be flatfish, raising the possibility their eyes might turn out to be in the intermediate position predicted by Darwin’s theory. To find out, Friedman tracked down examples of the fossils in two European museums and examined them with X-rays from a medical scanner. The results confirmed that the fossils are indeed ancient relatives of modern flatfish – and have eyes positioned on the skull at locations between those of earlier fish and those of modern flatfish. The discovery of missing links is cause for celebration among scientists. Yet such discoveries cut little ice with creationists, who simply point to the myriad other gaps in the fossil record that have yet to be bridged. And even when a missing link is found, creationists can simply demand fossil evidence bridging the two gaps thus created before and after the new link. It’s far from clear whether any amount of evidence will convince creationists to abandon their belief that all life was created by an omnipotent God. After all, such a
The response to this research has been overwhelmingly positive, and has come from various fields, from developmental biologists to palaeontologists. In particular, my colleagues are enthusiastic about having another case study for teaching evolution to their students.
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Resource
A feast for the mind Neil Shubin with a fossilised bone of Tiktaalik roseae, a fish that is thought to mark a transition between aquatic and land animals
The Universe Within A Scientific Adventure
dan dry
Neil Shubin and Allen Lane The Johns Hopkins University Press, 264 pages, ` 1,658
K A palaeontologist by training, Neil Shubin presents a panoramic view of our planet over the past few billion years, including how life as we know it came to be. Grounded in his own field work, with vignettes of hunting fossils in far-flung parts of the world, it reveals how our bodies have come to be due to cosmic events in the distant past. While this sounds somewhat esoteric, 88
April 2013
it comes across very clearly, with each chapter describing a different epoch and what its consequences are for us. The constant harping on about how we carry the signatures of these past episodes within us is somewhat artificial and irritating, but the arguments to defend his position are convincing. Since the coverage of this book is so sweeping over the aeons, it is inevitable that some of the treatment ends up being superficial, even occasionally slightly inaccurate
when Shubin strays too far from his own academic roots. It is deliberately written as a romping, extensive story – the ‘adventure’ of the title - full of photos of the scientists and explorers who have contributed to the unfolding of our narrative. I found these potted histories of individuals fascinating. Many of them were not names I knew, and their place in the development of scientific ideas was unfamiliar to me, and all the more interesting for that. The book carries the
reader along on a wave of enthusiasm for the subject, but leaves rather less room for reflection. I enjoyed it as a brief summary of many complicated and interwoven facets of our deep history, but I could not recommend it as a book that would serve as a useful reference guide. Athene Donald is a Professor of Experimental Physics at the University of Cambridge.
Get your clicks Parallel lives The man who tried to explain reality The Many Worlds of Hugh Everett III: multiple universes, mutual assured destruction, and the meltdown of a nuclear family By Peter Byrne Oxford University Press, 368 pages, ` 2,429
K We’re currently living through a period of revolutionary science that challenges just how we understand reality. Put in layman’s terms, there seems to be a lot more to the cosmos than we once thought.
A key figure in this upheaval was American physicist Hugh Everett III. Known in scientific circles as the ‘Many worlds interpretation of quantum theory’, Everett’s contribution resolves many problems by claiming that simple observations cause the Universe to split into parallel realities. Not surprisingly, Everett struggled to get fellow scientists to take his ideas seriously. He ended up quitting and working for the US defence industry. By all accounts, his life and personality were as complex as his theory, which may explain the lack of a biography of the man. Now journalist Peter Byrne has taken on the task of describing the many worlds of
Everett III’s theory states that everything that can happen, does, somewhere
Everett, but with various levels of success. The effort Byrne has put into understanding Everett is impressive, but the end-result is a confusing mix of straight biography and mind-bending quantum philosophy. It’s hard
to escape the feeling the author was simply overwhelmed by the sheer range of material he gathered. A brave, but flawed, attempt at a huge challenge. Robert Matthews is a visiting reader in science at Aston University.
The end of the world
Talking rubbish
The science behind the death of the Universe
Where does our garbage end up?
How It Ends: from you to the universe
The Story of Stuff: how our obsession with stuff is trashing the planet, our Communities and our Health
By Chris Impey WW Norton & Company, 352 pages, ` 1,403
K Particle physicist Frank Close once wrote a rather splendid book called End, which dealt with the fate of life, the Universe and everything in between. But that was 20 years ago, and
Chris Impey of the University of Arizona has quite rightly decided that it is time for another crack at the subject. In a very accessible style, he ranges from the inevitability of personal death outwards, dealing with extinction of entire species, and the fate of planets, stars and, indeed, the Universe. Unfortunately, the author is let down by some pretty ropey diagrams, but the text is fine. Good to dip into on a journey. John Gribbin is the author of In Search of the Multiverse (Wiley, 2010).
By Annie Leonard Free Press, 400 pages, ` 1,403
K This is the book version of Annie Leonard’s animated environmental crusade that follows the life-cycle of your stuff – from the extraction of its raw
materials to what happens when you chuck it away. It’s friendly and anecdotal in tone, offering glimmers of hope and alternative solutions, but the reality of our increasingly unsustainable predicament makes for some grim reading. So powerful is the spell we’re under, it’s hard to see how it can be broken. But with almost seven billion people, all hungry for stuff on a finite planet, we’d better wake up fast. Dallas Campbell is a British science presenter for the BBC. April 2013
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Get clicks Getyour your clicks Our pick of internet highlights to explore
H Website
H Website
Have Fun With History
Solar Stormwatch
H WEBSITE
http://havefunwithhistory.com/index.html
http://solarstormwatch.com
http://www.batcon.org/
This extremely comprehensive website is aimed at anyone with an interest in American history. The site is packed with video footage of US history-based dramas, documentaries and news programs, offering valuable insight into subjects ranging from Native American Indians and the history of the American West, to the development of the telephone and the Space Race. The site also includes footage about Edison’s 1895 talking movie experiment and educational films from the 1950s in addition to links to history-based activities to engage minds of all ages.
Science is a collaborative activity, and there are some innovative projects that use internet-connected computers in real scientific work by sharing spare disk space and processor power. One of the most notable examples is SETI@home, which distributed the analysis of radio signals over millions of ordinary home computers. Solar Stormwatch goes even further than this, and asks interested net users to do real science themselves. Once you sign up, you’re shown video recorded by the two STEREO solar-observation satellites and asked to find solar storms. You then make measurements and classify them.
Did you know that bats are essential to the health of our natural world. They help control pests and are vital pollinators and seed-dispersers for countless plants. Yet these wonderfully diverse and beneficial creatures are among the least studied and most misunderstood of animals. This is the perfect antidote to bat ignorance, providing in-depth information on White-nose Syndrome, which has devastated bat populations across the eastern United States over the past four years. The site features poetry inspired by the magic of bats by Scott McVay’s Master Ballerinas and Summer Bats by Hugh Eckert.
Bat Conservation
E WEBSITE
E WEBSITE
E VODCAST
The old articles, essays, poetry, cartoons and photographs found on this site have been lovingly collected from a number of different libraries, bookshops and yard sales throughout the United States and Europe. www.oldmagazinearticles.com
This site is a mine of information about Ancient Greece – from art and architecture to mythology to the invention of the Olympics. It also boasts a forum and a free essay research assistance service for students studying the period. www.ancientgreece.com
In 1964, American physicist Richard Feynman, gave a series of lectures that were filmed by the BBC. These videos are now owned by Bill Gates and form the heart of this excellent site, built by Microsoft to show off their experimental video server, Tuva. http://bit.ly/tuva1964
E PODCAST Krulwich on Science This podcast brings together a series of reports by Krulwich from Radiolab, a science show produced by the US National Public Radio service. The shows are intriguing, quirky and informative and come with a write-up and a transcript if you’d rather not listen. http://n.pr/krulwichradio
Old Magazine Articles
E WEBSITE
Ancient Greece
Project Tuva
Vikings: the Atlantic saga
E WEBSITE
Around 1000 years ago, Viking mariners set out from their colony in Greenland and became the first Europeans to discover North America. They called the land Vinland the Good, settling in today’s Newfoundland in Canada. You can experience the Vikings’ North Atlantic saga for yourself. www.mnh.si.edu/vikings
Napoleon.org
E WEBSITE
E WEBSITE
Home ot the Napoleonica online research centre, this bilingual (French/ English) site also features a guide to more than 100 Napoleonic museums and monuments. Alongside these features is an impressive gallery, including an image database and two filmographies. www.napoleon.org
If you need easy instructions on growing Venus flytraps, this site is for you. Presented in association with the International Carnivorous Plant Society, it is crammed with information about the conservation, and taxonomy of carnivorous plants. www.sarracenia.com/faq.html
Lying on your back in the garden looking for satellites can be fun, but it’s easier if you know when the International Space Station is going to be overhead. Tell Heavens Above which satellite you’re interested in and it will reveal when the satellite will be visible. www.heavens-above.com
The Carnivorous Plant FAQ
If you have a favourite website, blog or podcast that you’d like to share with other readers, please email
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Heavens Above
Buzz
We have always tried to make BBC Knowledge an interactive read. Here’s just a snippet of what we’ve been upto
Shaastra This year BBC Knowledge Magazine joined over 20,000 minds to celebrate at Shaastra, the annual technical festival of IIT Madras held on January 5-8, 2013. The four-day long festival saw events, such as Junkyard Wars, Robowars, Robotics and social initiatives like Ideas Challenge and Computer Literacy. In the spirit of Shaastra’s motto, ‘Igniting Imaginations’ a new science and technological themed event, School Quiz was held with teams competing from all over the world including Dubai.
BBC Knowledge - TopGear India Cars of the Future contest Driving forward the cover story of the February issue, Cars Of The Future, BBC Knowledge Magazine and TopGear India partnered up and held a week long quiz on Facebook. The daily winners received gift vouchers worth `500 from Hitplay.in Winners of the Quiz Abhijat Goyal, Sagar Udaykumar, Azgar Ullashariff, Shivanand R. Swami, Arun Bansal, Charan Sai and Rutuja Patil. Congratulations to them all!
corrigendum In the February issue of BBC Knowledge Magazine, we erroneously mentioned that the grand winner of the Knowledge Quotient App would receive a DVD Player instead of an LCD TV. The error is regretted.
If your college or club is organising an exciting event that you would like BBC Knowledge to partner with, write in to us at
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Science Olympiad Foundation
Why should schools participate? Science Olympiad Foundation (SOF) conducts workshops, seminars, science and IT competitions for students of different classes and age groups. SOF believes that the Olympiads bring out the best in participants, contribute to personality development and build their confidence by allowing them to compete with the best in the country and around the world. Why SOF is a must for your child? The students are exposed to a variety of complex problems that require a high level of analytical ability and proficiency in using concepts spread across a variety of subjects. To help them gauge their academic capabilities within the school at a national or international level, the students get ranks based on the marks they score. Details for registrations: Students from Classes 1 to 12 can participate, while registrations from schools are received in the prescribed pro-forma. The registration sheet for schools or students and the information booklet are posted to schools all over India and abroad. www.sofworld.org/registration-form.html Awards to be won: Class toppers, International and State winners are awarded prizes worth a total of ` 6 crores. For further information about award details visit: www.sofworld.org/bigger-prizes.html
is a non-profit organisation established for promoting science, mathematics, english and computer education in Asia SOF believes in seeking out, identifying young geniuses and providing them with a unique competitive platform. To further this cause, SOF endeavours to: • Identify and nurture future scientists, technologists and IT talent at the school level. • Encourage students’ participation in national and international science and IT competitions, programmes and events. • Instill a feeling of belonging to the national and global science and IT fraternity. • Infuse a healthy competitive spirit through reward based Contests (Olympiads). • Bring about a transformation in the classroom approach to science and IT making it more interactive, practical and innovative. • Disseminate knowledge and information on the latest developments in science and technology. • Project SOF as a Centre of Excellence that could cater to different schooling institutions in the areas of methodical research, new educational tools, special publications and expert advice. SOF holds four major challenging aptitude testing platforms that are focused on Computer knowledge, Science, Mathematics and English. They are the National Cyber Olympiad, the National Science Olympiad, the International mathematics Olympiad and the International English Olympiad. For further information visit www.sofworld.org or email info@ sofworld.org
Upcoming Exams
Promotional Feature
Science Olympiad Foundation conducts four exams in a year National Cyber Olympiad (NCO) The first of its kind in the country, the National Cyber Olympiad is now a global search competition that aims at identifying and nurturing cyber talent amongst youngsters.
National Cyber Olympiad: The first round of NCO exam will be held on September 19, 2013 and October 4, 2013 at all participating schools.
Focus: Mental Ability, Logical & Analytical Reasoning in computers and IT
How to prepare: Download previous test papers, practice tests and SOF recommended books for the NCO exam here www.sofworld.org/nco
NCO: www.sofworld.org/nco National Science Olympiad (NSO) Students from the Class 1 onwards are invited to participate in the National Science Olympiad to test their understanding, level of knowledge, applications and power of reasoning. Focus: Mathematics, Physics and Chemistry NSO: www.sofworld.org/nso International Mathematics Olympiad (IMO) This aptitude platform identifies and encourages the mathematical creativity of children in schools across India and abroad. Focus: Mathematics IMO: www.sofworld.org/imo
International English Olympiad (IEO) This is a one-of-a-kind examination held in collaboration with the British Council in India. Focus: English language IEO: www.sofworld.org/ieo
NCO: www.sofworld.org/nco/faqs
National Science Olympiad: The first round of NSO exam will be held on November 15 & 28, 2013 at all participating schools. NSO: www.sofworld.org/nso/faqs How to prepare: Download previous test papers, practice tests and SOF recommended books for the NSO exam here www.sofworld.org/nso International Mathematics Olympiad: The first round of IMO exam will be held on December 5 & 19, 2013 at all participating schools. IMO: www.sofworld.org/imo/faqs How to prepare: Download previous test papers, practice tests and SOF recommended books for the IMO exam here www.sofworld.org/imo International English Olympiad: The first round of IEO exam will be held on January 16 & 30, 2014 at all participating schools. IEO: www.sofworld.org/ieo/faqs How to prepare: Download previous test papers, practice tests and SOF recommended books for the IEO exam here www.sofworld.org/ieo
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Gadgets TOP SCIENCE APPS that will set you apart from the nerds
Wolfram Alpha Enter questions, calculations, names, and places across thousands of topics, and the app will ask the big Wolfram Alpha computation engine in the cloud for answers. Price: FREE
Have suggestions for any gadget/application? Share with other readers, email
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For the
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Moon Atlas Pinch and zoom across the Moon. Get information on all the phases, and pick out nearly 2000 named features on its surface, including the 26 spacecraft left behind. Price: `350
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Cry Translator New-born babies cry in different ways depending on what’s bothering them, and this app attempts to identify hungry, sleepy, bored, annoyed and stressed wailing. Price: `270
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After identifying your current location, this app shows you a map of local businesses and what they’re pumping into the air, water and ground. Price: FREE
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Lists all the discovered planets orbiting other stars, with visualisations, orbits and sky charts showing you where to point in the night sky to impress your friends. Price: FREE
Point your iPhone at the night sky to see the names of the stars above you, or sit back and watch the animation of what’s coming into view above the horizon.
Fractals Certain simple equations can generate complex, beautiful images called fractals. With this app you can create your own patterns, and send them to your number-hungry friends. Price: `170
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Soak up the Sun The Sun Jar designed by Tobias Wong captures a piece of the sun in a jar. Well… kind of. Using a mason jar and advanced high-tech energy efficient lighting, the solar cell, when exposed to sunlight creates, an electrical current that charges the battery in a few hours. It stores this energy and can light up the jar for the night with LED lamps for up to five hours. Price: `1,999 • www.hitplay.in
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April 2013
Earth’s Greatest Mysteries Turn the pages of time, literally as you unravel the myths of an era gone by, discover unknown technologies, learn about fossil discoveries and treasure hunts and learn of cave paintings that depict impossible events. This would pique the interest of Indiana Jones I assure you. Price: FREE
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Equation Notepad Prone to misplacing your equation scribbled notes that you were sure would change the laws of physics or chemistry? With this app, your equations stay right in your phone. You can create any sort of equations such as polynomials, tensor equations matrices that you can recall at a later time thanks to its intuitive 2D navigation system. Price: `70
The unthinkable has happened here. Engineering and physics have joined forces to create a puzzle that is actually fun! Space Physics gives you a marble, a goal and obstacles in between and asks you to put your grey cells in action to draw a way to get the ball to its destination. Price: `100
TED Inspiring, mind-blowing and often an eye opener, the app brings remarkable people and remarkable ideas of TED talks at your fingertips. About 1200 talks are added every week, which you can store and view later.
Metal Detector
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We have come so far in science that now all you need is your phone and this app to identify the level of magnetic field around you. It identifies any metal in the area and measures the magnetic field around and also helps you identify the different metals in you vicinity as you wave the phone in an infinity pattern. Price: FREE
Mobile Observatory Fancy your morning cuppa with a side of astronomy? The Mobile observatory app is the complete astronomy map for your android phone. It lets you know if your location is suitable to view the next lunar eclipse or when the next bright comet will whizz part our beautiful planet. Signing up for the night sky never looked so exciting.
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April 2013
97
The
last word
The next step in the evolution of life is going to be human-induced says Dr Renee Borges
“A million years from now, who can say whether humans will still roam the earth? ” “
…whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.” Charles Darwin: The Origin of Species (1859). When life is viewed through evolution-tinted glasses, much of it makes sense. The process of natural selection that involves the generation of variation in phenotypes as a result of random mutations, the greater success of some phenotypes over others, and the heritability of these successful phenotypes could lead to what Darwin called descent with modification. To this must be added the process of random genetic drift as well as physical constraints of form relative to function given the available materials. The patterns of life are governed by such evolutionary processes. What is the advantage of viewing life through evolutiontinted glasses? With this perspective, we can understand, for example, why lean Africans from the Rift Valley usually win marathons, and why athletes with the physiognomy of Usain Bolt usually dominate sprint events. This harks back to the evolution of slow twitch and fast twitch muscle fibres which facilitate endurance running for long periods of times or the burst of energy required in sprints. Better oxygen capacity in the muscles of marathoners may have also been an ancestral 98
April 2013
adaptation to the hypoxic high altitudes of the Rift Valley, or to the endurance required to keep pace with and hunt down prey using primitive weapons. This is the result of natural selection. However, what about unnatural selection? What if, with our technology, we are able to engineer über-athletes, just as scientists have engineered ‘Schwarzenegger mice’ by introducing suitable genes into normal mice? The threat of genetic doping in sports looms large and would be devastating in a world freshly recovering from the doping scandal of the alleged ‘Superman’ Lance Armstrong. His was an unnatural phenotype that won many races. Through the perspective of comparative biology and evolution, we may be able to discern the natural limits of human endurance or speed. However, humans have crossed speed barriers by “legitimately” using aids that they have copied from nature or engineered with their own creativity. For example, swimsuits designed on the basis of shark skin have been credited with contributing to record-breaking Olympic performances. Here, humans have extended their own natural phenotype by copying and adopting that of sharks and have thus enhanced their performance. Shark skin has been under natural selection for millions of years, and has evolved to reduce drag and
to increase the hydrodynamic efficiency of a shark in water, making it a most successful predator. Besides the beautiful view through these evolutionary lenses, what else can such a perspective provide? In today’s world, we have the technology to make organisms to order, i.e. we can insert genes into organisms and generate transgenic forms. This has been a boon for many products, e.g. we have inserted the insulin gene into bacteria which now produce insulin for us under laboratory conditions. This is useful as long as we can control the products of our unnatural selection. When we insert genes into crops to control pests, as has been done with the gene for a toxin from Bacillus thuringiensis (Bt) that is toxic to many insects, what do we see through an evolutionary perspective? We see that the insects, which are also under natural selection to detoxify poisons, quickly acquire resistance to Bt toxin. This necessitates the engineering of new transgenic plants in which new toxins are introduced, via new combinations of alien genes. One can easily imagine a scenario wherein monocultures of transgenic plants, which have been planted over large areas after uprooting the natural diversity of traditional crop cultivars, have to be replaced by the next generation of newer transgenics, and so on, endlessly.
In the meanwhile, evolution in the insects has progressed at a much faster pace, rendering them the winners in the transgenic race. In this process, humans have lost their natural diversity of crops and the wild relatives of crop plants. This would have served both as reservoirs of newer genes for future experiments, as well as a vast gene pool from which natural selection could act to reward better insect-resistant varieties. The evolutionary perspective makes one realise that it is more powerful and wiser to preserve the natural variation that has survived battles against enemies over millennia than to eliminate most of it on the promise of technological prowess. What then of the future? With evolution tinted glasses and the lessons from Earth’s history, we know that ‘life’ is resilient, but life as we know it today is not. Individuals and species have won contests, but many have also lost them. Species have gone extinct, only to be remembered in the genes they may have shared with others more successful than them. A million years from now, who can say whether humans will still roam the Earth? Renee M Borges is Professor and Chairperson of the Centre for Ecological Sciences, Indian Institute of Science, Bangalore. She works on the ‘hows’ and ‘whys’ of symbiosis. She studies the sensory ecology of interactions between figs and fig wasps, ants and plants, termites and their fungal crops, as well as plants and their pollinators.
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