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September 09 Can Science Improve Man's Best Friend?Can Science Improve Man's Best Friend?ScienceDaily (Sep. 8, 2008) — If you could design the perfect dog, what would it look like? Tall, short, fluffy, wiry, black, white, tan or brindle? Australian Shepherd. (Credit: iStockphoto/Virginia Hamrick) While animal buyers often look closely at physical characteristics, behavioural traits can make the difference between a dog becoming a much loved and pampered family member, or a mistreated or neglected unwanted animal. According to Monash University researcher Dr Pauleen Bennett from the School of Psychology, Psychiatry and Psychological Medicine, science and breeding can be used to produce dogs that have characteristics desired by average dog owners and are well suited to the domestic environment. "For many people the dog is the only living animal with which they have any form of regular personal contact and of course, many pet dogs are treated like royalty," Dr Bennett said. "Yet, animal welfare shelters are forced to put to death thousands of unwanted dogs each year, and many pets are still subject to cruelty, neglect or inappropriate care. Even the most well-intentioned owner can place their dog's wellbeing at risk through exposure to the stresses of high density living, anxiety triggered by long hours spent alone, and even obesity or diabetes caused by overfeeding." Characteristics Australian owners want in their pet dogs include being friendly, obedient, affectionate and healthy, while undesirable behaviours included nervousness, destructiveness and excitability. "Canine behavioural traits are highly heritable, so in theory at least, we can genetically fix desirable characteristics in dog breeds. Just as we have previously produced dogs able to herd sheep or pull sleds, so we should be able to breed dogs better suited to their role as companions," Dr Bennett said. "Successfully matching the dog, its requirements and behavioural traits with the understanding and desires of the owner should mean the animals are more likely to enjoy good welfare throughout long, healthy and happy lives." Dr Bennett said it was an exciting time to be working in her area. She presented her research at the 2008 International Animal Welfare Conference on the Gold Coast, Sunday 31 August to Wednesday 3 September. "The whole issue of animal welfare is gaining momentum socially and Australia is well-placed to lead the world in developing socially responsible relationships with animals," Dr Bennett said. September 05 Three Ice Shelves Breaking Up in Arctic
Breaking Up | Video: Discovery Earth Sept. 3, 2008 -- Two ice shelves in Canada's far north have lost massive sections since August while a third ice shelf now is adrift in the Arctic Ocean, said researchers Wednesday who blamed climate change. The entire 50 square-kilometer (19 square-mile) Markham Ice Shelf off the coast of Ellesmere Island broke away in early August and is now adrift, while two sections of the nearby Serson Ice Shelf detached, reducing its mass by 60 percent or 122 square kilometers (47 square miles). Ward Hunt Ice Shelf, which halved in July, lost an additional 22 square kilometers (8.5 square miles). "These changes are irreversible under the present climate and indicate that the environmental conditions that have kept these ice shelves in balance for 4,000 years are no longer present," said Trent University's polar expert Derek Mueller. Canada's summer ice shelf losses now total 214 square kilometers (82.5 square miles), which is more than three times the area of Manhattan Island, the researchers said. Extensive cracks in Ward Hunt, the largest remaining ice shelf, means it will continue to disintegrate in the coming years, said Luke Copland, director Ottawa University's cryospheric research lab. Copland blamed "very warm temperatures" and "reduced sea ice" for the crumbling ice shelves. The sea ice usually braced the shelves and without it, wind and waves more easily broke them apart, he explained. The coast of Ellesmere Island has also warmed an average of two degrees (Celsius) in the last 50 years, he said. In winter, temperatures are now five degrees warmer, making it more difficult for ice lost in summer to recover in winter. "We see that warming is concentrated in the winter," Copland said. "It's part of global warming. When we warm up the planet it gets concentrated close to he poles." "Usually the ice shelves would use the winter to recover from the previous summer. They would reform, ... but the ice shelf can't recover in the winter anymore." "We have now reached a threshold where (the environment) is too warm for these ice shelves to exist anymore," he said. "What it tells us is that the Arctic is changing." "It underscores the rapidity of the changes, how quickly things are moving along in the Arctic," Mueller said. "Its not just the ice shelves that are changing. These changes are occurring in concert with sea ice reduction and other indications of climate change." The Ellesmere ice shelves were formed some 4,500 years ago, composed of sea ice, accumulated snow and glacier ice up to 40 meters (131 feet) thick. The detached pieces broke into numerous 'ice islands' (tabular icebergs) whose fate could take many forms, said researchers. Martin Jeffries of the National Science Foundation and University of Alaska Fairbanks, and who has studied the Ellesmere ice shelves since 1982, said they could float along the northern edge of Queen Elizabeth Islands toward the Beaufort Sea or enter the Canadian Archipelago. The Canadian Ice Service is tracking the broken pieces. Strongest Storms Grow Stronger Yet, Study SaysStrongest Storms Grow Stronger Yet, Study Says A new study finds that the strongest of hurricanes and typhoons have become even stronger over the last two and a half decades, adding grist to the contentious debate over whether global warming has already made storms more destructive. “I think we do see a climate signal here,” said James B. Elsner, a professor of geography at Florida State University who is the lead author of the paper, being published in Thursday’s issue of the journal Nature. The study, which also found that more typical, less powerful tropical storms had not become stronger over the 26-year period studied, is consistent with other researchers’ hurricane models, Dr. Elsner said. With oceans expected to continue warming, “one would expect more 4s and 5s,” he said of Category 4 and Category 5 hurricanes, those with maximum sustained winds of at least 131 miles per hour. About 90 tropical cyclone storms form each year around the world. In the Atlantic, the stronger ones, with winds of at least 74 m.p.h., are hurricanes; the equivalents in the Pacific and Indian Oceans are typhoons. Ten named storms have formed in the Atlantic this hurricane season, which continues to the end of November. Heat from the warming oceans will provide more energy to spin up hurricanes and typhoons, but the changing climate could also heighten conditions like wind shear — winds blowing at different speeds and different directions at different altitudes — that tend to tear a storm apart. Because of these environmental factors, most storms fall far short of their maximum possible intensity. But Dr. Elsner, along with Thomas H. Jagger, a postdoctoral researcher at Florida State, and James P. Kossin, a research scientist at the University of Wisconsin-Madison, reasoned that warmer waters increased the possible intensity and that storms that develop in ideal conditions might have become stronger. Having examined satellite data from 1981 through 2006, a period in which sea surface temperature rose to 83.3 degrees Fahrenheit from 82.8 degrees, they concluded that the highest wind speeds of the strongest storms averaged 156 m.p.h. in 2006, up from 140 m.p.h. hour in 1981. The increases in cyclone intensity were greatest in the Atlantic and Indian Oceans. Because the data came from one set of satellites, the scientists avoided some of the calibration difficulties that had troubled earlier studies. “This study offers definitive evidence that there are more of the very strongest hurricanes around the world, even though the total number of storms globally shows hardly any trend,” said Kerry A. Emanuel, a professor of atmospheric science at the Massachusetts Institute of Technology, who suggested in 2005 that global warming had already intensified cyclones. Christopher W. Landsea, science and operations manager at the National Hurricane Center, who has been skeptical of the connection, said the statistical methodology in the new study was excellent. But Dr. Landsea questioned the underlying data, particularly corrections for data taken from the Indian Ocean before 1997, when there were fewer satellites observing the storms. He also said that the conclusions might have been skewed because the starting point of the data, 1981, coincided with a relatively quiet period of Atlantic hurricane activity, whereas the ending point, 2006, coincided with an active period that began around 1995. “The paper has some elegantly calculated statistics, but these are generated on data that are not, in my opinion, reliable for examining how the strongest tropical cyclones have changed around the world,” Dr. Landsea said. Thomas R. Knutson of the Geophysical Fluid Dynamics Laboratory at Princeton said the data involved too short a period to draw long-term conclusions. “One is left with a very suggestive result and a very interesting result,” Dr. Knutson said, “but it’s not a definitive smoking gun for a greenhouse warming signal on hurricanes.” The boat builders of Salaya, IndiaThe boat builders of Salaya, IndiaWooden boats have been used in the Arabian Sea for centuries. But today, they are built bigger, in greater numbers and at higher costs than ever before. Words by Richard Orange. Photos by Michael Rubenstein
![]() Just a few hours after leaving the shelter of the Iranian coast, Haroon Sanghar, captain, or tindal, of the Faize Makdumi, gives the order to hoist the sail. ‘Fare ha kar,’ he yells and squints forward, watching the triangle of white cotton unfurl until he feels some of the strain come off the boat’s engine. After ten gruelling and isolated months shipping livestock on the lawless Somalia coast, Haroon and his 15 crew are now only days from home. A clean-shaven man in his mid-20s, Haroon is the youngest tindal from the Sanghar family – one of the most prominent of the clans who build and operate Gujarat’s traditional wooden dhows, known as vahans. For centuries, these boats have plied the Arabian Sea from the island of Zanzibar to the coasts of Arabia, Iraq, Iran and Pakistan. ‘We think we are the lucky people,’ says Haroon’s older brother Hussain. ‘We go everywhere: we go to Dubai; we go to Iraq. We are free.’ But Faize Makdumi and the Sanghar family’s way of life are no relics from the past, soon to be swept away in India’s tide of modernisation. In Salaya, the capital of Gujarat’s traditional boat-building industry, vahans are currently being built bigger and in greater numbers than at any time in living memory. Big business Propped up on his scooter on the muddy shoreline, Haroon is enjoying a well-earned month of shore leave. ‘It’s great,’ he says. ‘After a long time, we come back to play with our families, joking with them and sitting with them.’ But behind him rises the hulking wooden hull of the largest boat the village has ever built – a giant vahan capable of carrying more than 1,000 tonnes of cargo, and twice as large as was standard a few years ago. It stands improbably high against the lush coastal wetlands behind, its deck swarming with carpenters, labourers and errand boys making the finishing touches. This is a cargo vessel on the same scale as the East Indiamen – the ships that the European merchants used to transport cotton, opium and spices from this same coast almost 300 years ago. ‘It’s like competition,’ says Hussain, explaining the growth of vahans. ‘When I came into this business, there were only 300- and 500-tonne boats – not more than that. But then in Pakistan, they started making 600 and 700 tonnes. If we didn’t start making them, we would have lost business.’ Hussain’s friend Adam Bhaiya, who heads the Salaya Sailing Vessel Owners Association, says that today, the village has 25 boats under construction, whereas just a few years ago, there would have been only two or three – and few of them are smaller than 700 tonnes. The ship’s an impressive sight and I’m keen to meet the man behind it – Salemamad, the gaider or ship’s architect. ‘He is a very busy man,’ Hussain says apologetically after we’ve waited the best part of a day for him to arrive. ‘He is the most talented gaider. He has four boats under construction.’ But just as we are leaving, Hussain pulls his van to an abrupt halt. ‘There,’ he says, pointing. ‘That is Salemamad.’ It would be difficult to conceive of a less likely naval engineer. Salemamad’s mouth bulges with tobacco and betel nut, the red juice from which stains both his teeth and his sun-cracked lips. A dirty tunic covers his swollen gut. For Salemamad, the launch fulfilled an ambition. ‘I was glad to make this launch,’ he says. ‘I was wishing to make a very big launch for some time, but there was no owner who wanted to go to 1,000 tonnes.’ That they did shows tremendous faith. Salemamad had no written plan to show them before he laid down the first plank, and yet the family, distant relatives of Hussain, invested more than 15 million rupees (£350,000) in the project – a huge sum for rural India. When you ask him where the measurements were, Salemamad just smiles and taps his head. ‘He is not having any kind of degree or studies,’ says Hussain. ‘He is not knowing even how to sign his name – just a fingerprint. But he can make this launch.’ Salemamad’s lack of education makes him the norm rather than the exception. Only a quarter of Salaya’s people can read and write, next to an Indian average of 60 per cent. Shipbulding here is a practical rather than a theoretical lesson. ‘We learn it from our forefathers,’ says Hussain. ‘First of all, our old people are knowing it and we are learning about it step by step – that this kind of wood is used, that we build it here like that.’ Hussain estimates that Salaya’s people have been building boats for ‘maybe 150 years’. But the reality is certainly longer. Shipwrights from Gujarat even built frigates for the British Navy that went on to fight in the battle of Trafalgar. Just in case British naval seamen were in any doubt, Nusserwanji Wadia, a shipbuilder from Surat, carved the words ‘This ship was built by a d----d Black Fellow AD 1800’ into the central beam of one of them. Working with wood In a dock in front of one of Salaya’s three Sufi shrines, Kasim, another Sanghar, is overseeing the construction of a 700-tonne boat. Nine months into its construction, its skeletal form is slowly beginning to take shape. Kasim, as smart as Salemamad is scruffy, is dressed in the crisp white tunic and skull cap of a haji, a man who has visited Mecca; almost all of Salaya’s boat builders are Muslims. He stands confidently on a beam high above the boat’s wooden floor as he instructs carpenters heaving on chains to pull the latest plank into place at the top of the boat’s hull. He stops to take measurements, using string and weights, and marks the hull with charcoal where the new wood should be slotted. ‘If you want to learn this job, first you must learn carpentry,’ he says, sitting to drink a cup of sweet tea on a log beside the boat. ‘But the most useful thing is your mind: if you have a sharp mind, you can get it. If you don’t have such a mind, then it is impossible to be a gaider.’ Hussain says gaiders don’t need written plans because they build to a formula, beginning with the single beam, called a pathar, that becomes the entire base of the hull. The pathars are each cut from a single huge trunk known as a malaysia, after the country from whose forests they frequently come. Then come beams for the aft and bow, which form the anchors from which planks are bent around to form the hull. As boats are always built to the same set proportions, the length of the pathar determines the dimensions of everything else. Kasim says building a 1,000-tonne boat would be no particular challenge – it simply means choosing a longer pathar to start with. He is considering a 1,200-tonne boat for his next project. But Adam, the gaider of the boat next to Kasim’s, disagrees. ‘It is more difficult to make 1,000 tonnes,’ he explains. ‘We use bigger pieces, so it is more difficult to bend the wood and turn it, and if it doesn’t bend, it may break.’ Adam says the number of boats being built has also brought problems. ‘We are making 25 boats and each boat needs ten carpenters. There aren’t 250 carpenters in Salaya,’ he says. That explains the darker South Indian faces of some of the workers. Today’s boom is drawing in artisans from Andhra Pradesh in the south, and Bihar and Uttar Pradesh in the north. Carpenters’ rates have nearly doubled to 200 rupees a day. Salaya clearly has more than enough work for every male of its 27,000-strong population, even boys who have yet to reach their teens. But not all want to work as boat builders. As we tour Salemamad’s boat, Hussain calls over 14-year-old Nasir, who is working as a helper. Nasir has been working on boats for three years, starting as one of the boys that provide the carpenters with their tooth-achingly sweet cups of tea. He has no interest in becoming a gaider. ‘I don’t have that kind of mind,’ he says. ‘I am in trouble even right now for forgetting something.’ What Nasir wants is to reach his 18th birthday, collect his seaman’s card and go to sea. Life on the ocean wave Today, Salaya’s business is all about boat building. But during the four-month monsoon, when the town’s fleet returns, its waters are crammed with wooden boats under repair and its streets are abuzz with 3,000 returned sailors. Salaya owns 180 of India’s 700-plus traditional cargo sailing vessels. In the past decade, they have sailed as far as South Africa and even to Singapore (although that was to deliver a vessel for a Japanese maritime museum). But the centre of the universe is Dubai. ‘Dubai for us is like a local port,’ says Hussain. ‘We think we are in India.’ The Emirates boom town’s ever-growing appetite for food has triggered today’s surge in vahan construction as the smaller boats are better suited to handling small cargos of produce from villages across India, Pakistan and Iran. The life of the sailors is risky but adventurous. Shipwreck, piracy and even smuggling still occur. Salaya’s boats regularly come up against pirates in Somalia, and a crew member was kidnapped only a few months ago. During the 1980s, smuggling was rife. Haji Ismail Sumbhania, the king of India’s modern-day smugglers, was born here and ran a vast operation, smuggling cargos of gold, silver, guns and drugs before he was gunned down in a 2005 firefight with the Mumbai police. Fire and shipwreck strike often. Next to Salemamad’s hulk sits the charred hull of the 700-tonne MSV Alibag, which Hussain and his brothers had worked on for three and a half years when it was destroyed in a blaze in March, just days ahead of its first voyage. ‘We lose four to five vessels a year,’ says Adam, who doubles as an insurance agent. ‘Every family has its tragedy.’ At the start of February, one of Salaya’s vessels sank near the coast of Iran, and the crew were left clinging to a water tank for five hours before they were rescued. Hussain remembers his days as a tindal, when, during a trip to Mumbai, he was caught in a storm so brutal that the crew gave up even trying to control the boat. ‘Down was water, and up was God,’ he says, shaking his head. ‘No-one had any idea where we were. No-one thought we were safe. We could only pray.’ It’s a lot safer today, however, than in the days before engines, when vahan sailors were entirely at the mercy of the wind. Ishmael, an old man with leathery skin and crinkled eyes, travelled between Salaya, East Africa and the Gulf using only sails during the early 1960s. ‘In those days it was very hard,’ he says. ‘We had only sextant and compass, and we had to have very much knowledge of the sun and stars.’ Sail away Sails remain crucial to vahans’ survival even today, because they qualify the ships as ‘country class’ vessels. Tindals of these boats don’t even need to be able to write, let alone pass merchant seaman exams. In January, the cargo ship MS Beluga SkySails used a giant computer-controlled kite to catch wind on a voyage from Germany to Venezuela, cutting fuel use by 15 per cent. Haroon estimates that putting the sail up on the Faize Makdumi can do even better – saving as much as a quarter of the fuel used. ‘It will maybe happen that we return to the sail if the price of fuel keeps coming up,’ Hussain muses. ‘We have not forgotten how to sail.’ July 2008 10 Ways Methane Could Brake Global Warming—or Break the Planet10 Ways Methane Could Brake Global Warming—or Break the PlanetThe enigmatic gas is a valuable fuel and a dangerous digestive waste product. by Susannah Locke
Methane is a paradox. It increases global warming at the same time that it promises abundant alternative energy. The gas is all around the planet, from the atmosphere to deep below seabeds. Here are 10 trends and discoveries that may determine methane's ultimate role in the health of the environment:
10 Ancient Pollution Einstein's 23 Biggest MistakesEinstein's 23 Biggest Mistakes
A new book explores the mistakes of the legendary geniu The man with the big ideas wasn't so good with the details. In Einstein's Mistakes: The Human Failings of Genius (W.W. Norton, $24.95, excerpted below), Hans Ohanian writes that Albert often let his intuition overrule flawed proofs and shaky math. Maybe you'll feel a little better about your own flubs. (See this earlier DISCOVER story for more detail on Einstein's biggest flubs: thinking black holes were impossible, believing the universe was static, and that "God does not play dice." Also see DISCOVER's recent special issue on Einstein.) Chronology of Einstein’s Mistakes
3 People Who Are Pushing the Edge of Science3 People Who Are Pushing the Edge of ScienceGrowing electronics with viruses, finding alien life, and quantum privacy protection. by Jane Bosveld; illustrations by Riccardo Vecchio
Angela Belcher
Edge work: “Programming” viruses to perform useful tasks Why? It is clean and efficient. When 40-year-old materials chemist Angela Belcher was a child, she wanted to be an inventor. “I would try to build things out of scrap material that we had in the garage,” she says. To her disappointment, everything she made had already been invented. Then, in college, she “fell in love with large molecules” and found a whole new way to build things. Although Belcher was interested in DNA, the molecules she most loved were proteins. She wrote her doctoral thesis on how abalone grow their rough outer shells and pearl-like inner shells, the main difference between the two being a simple shift in protein sequences. “It’s pretty amazing,” she says. “If organisms like abalone have precise control at a genetic level, I realized it might be possible to program an organism to grow other kinds of material. Why not use genetic information to build a protein that can grow a semiconductor?” In a series of experiments at MIT, Belcher, working with a team of about 30 students and postdocs, has successfully programmed viruses to incorporate, then grow, a variety of inorganic materials, including nanoscale semiconductors, solar cells, and magnetic storage materials. Separately, she is using yeasts as scaffold organisms because of their ability to grow many different materials. “We look at yeasts as factories,” she explains. “Instead of Budweiser, there’s Nanoweiser.” Belcher has begun working with the U.S. Army on nanoscale batteries that would weigh a fraction of what current batteries weigh and be woven into a soldier’s uniform. She is also training viruses to “find mistakes in materials and give off a signal.” One possible application: spraying viruses on an airplane fuselage to check for microscopic defects. In addition, the National Cancer Institute is funding Belcher to use viruses to find peptides that can specifically identify cancer cells. “We have a long way to go,” Belcher says. “But one of the things I like about biology is that you have evolution on your side.” Dimitar SasselovEdge work: Finding life on planets outside our solar system In his quiet, modest way, Dimitar Sasselov is working to answer one of science’s most explosive questions: Is there other life in the universe? Sasselov, a 46-year-old Harvard University astronomer and director of the university’s Origins of Life Initiative, is looking for life-sustainable extrasolar planets—planets that are circling suns in other solar systems. Among the 270 extrasolar planets discovered so far, there is probably one living world, according to Sasselov. Sasselov says a planet needs to have two things to sustain life. First, it must allow complex biochemistry to develop. For this to occur, the temperature on the planet has to fall within a certain range. Too far from its star and the surface may be too cold to support the necessary reactions; too close and it may be too hot. The second must-have for life is a recycling of gases and minerals from the planet’s interior to its exterior—known as the carbon cycle —which keeps the atmosphere in balance over long periods so life can emerge and survive. The alien life we are most likely to find will be microbial, Sasselov explains. In fact, he expects that the first living planet we discover will resemble what Earth looked like a billion years ago, when life had not yet evolved beyond bacteria, simple algae, and other microorganisms. “But Earth is just one possible pathway for the emergence of viable biomolecules from chemistry,” he says. “Are there multiple pathways? Do all chemical pathways converge to one or two or three possible ones to produce life?” Sasselov is working with planetary scientists and cosmochemists to answer these questions by analyzing concentrations of molecules in the universe and on the extrasolar planets they suspect may harbor life. Sasselov doesn’t think that discovering life on another planet will change much on Earth. “It did not make a big difference 450 years ago whether Earth was the center of the solar system or whether the sun was,” Sasselov explains. “It’s the same now. Nothing really would change.” People would, however, realize that “the place we live in is much bigger than we ever imagined,” he admits. “That is world-changing.” Gilles BrassardEdge work: Using quantum mechanics to protect our privacy Privacy wonks should love Gilles Brassard. He is the guy who has delivered their seemingly impossible desire: an absolutely confidential way to send electronic messages. Unfortunately, it involves quantum mechanics, the twilight zone of physics. Brassard, a 52-year-old professor of computer science at the Université de Montréal, turned the wild idea of using the quantum world to send messages electronically into something real. Soon it may be essential. Quantum cryptography ensures complete privacy because any attempt to observe the transmission will change the message. It is a basic principle of quantum mechanics: The act of observing affects the thing observed. “If I send you information in the form of quantum signals and someone tries to eavesdrop on that signal,” Brassard explains, “the act of eavesdropping will disturb the signal. It will also alert the recipient if the transmission has been compromised.” As a child Brassard wanted to be a mathematician, but he became fascinated with programming when he took a computer science course at the Université de Montréal, which he entered at age 13. A decade later, in 1979, he became fascinated with how the strange properties of quantum mechanics could be harnessed to send confidential messages without an elaborate encoded key, as required by conventional cryptography. In 1983 he codeveloped BB84, the first practical quantum cryptography scheme, and he continued to refine it for years. Today, along with physicists like Christopher A. Fuchs of the Perimeter Institute for Theoretical Physics in Waterloo, Ontario, he is also reexamining the foundations of quantum mechanics to see where information fits in. Brassard suspects that underlying the fundamental laws of the universe are information theory axioms rather than waves or particles. “I don’t have any formal training as a physicist,” he says, “but sometimes that’s good. It helps you see things differently.” 20 Things You Didn't Know About... Telescopes20 Things You Didn't Know About... TelescopesFrom Galileo to the Hubble, viewing space has come a long way. by Susan Kruglinski
1. Conventional wisdom says that Dutchman Hans Lippershey invented the telescope in 1608, but legend has it that the device was really invented three years earlier by kids playing with lenses in a spectacle-maker’s shop. That kind of stuff used to happen in the days before the Xbox. 2. Early telescopes sold like mad to merchants, who used them to spot approaching trade ships in hopes of beating out competitors. 3. Telescopes gave rise to the first high-speed telecommunications networks: spyglasses that were used to relay semaphore signals from miles away. 4. Galileo was the first to turn the telescope skyward, leading to the discovery of Jupiter’s satellites and craters on the moon. Less cleverly, he also pointed his telescope at the sun, which may have triggered his later blindness. 5. Ireland’s “Leviathan of Parsonstown,” a 40-ton reflecting telescope built by the Earl of Rosse in 1845, was the world’s largest for seven decades. But wet weather kept it shut down most of the time. 6. Almost every major observatory since then has been built in the clear, thin air of a remote mountaintop. 7. To deliver the 100-inch mirror for the Hooker Telescope on Mount Wilson in California, nearly 200 men with ropes guided a truck along a tortuous, eight-hour drive to the top. 8. But it was worth it. The Hooker Telescope proved that other galaxies exist and that the universe is expanding. 9. Today, using an Internet-based telescope such as the Seeing in the Dark scope at New Mexico Skies, any amateur can command a robotic observatory while lounging at home. 10. Most professional astronomers now work that way too, operating telescopes remotely with computers and rarely looking through an eyepiece. 11. Long time coming: NASA launched the Hubble Space Telescope in 1990, seven years late and $2 billion over budget. 12. Hubble’s eight-foot light-collecting mirror had to be polished continuously for a year to an accuracy of 10 nanometers, about 1/10,000 the width of a human hair. 13. Unfortunately, the contractors polished the mirror precisely wrong, off by a painful 2,200 nanometers. 14. Since the problem was fixed in 1993 by installing corrective lenses, Hubble has become the source of roughly 25 percent of all published astronomy research papers. 15. Telescopes that pick up radio waves, not visible light, got their start in 1932 when engineer Karl Jansky noticed that the static plaguing his equipment varied on a daily schedule. His antenna was picking up celestial radio sources rotating in and out of view. 16. In 1965 engineers Arno Penzias and Robert Wilson were also bugged by microwave static, this time from every part of the sky. After eliminating poop from roosting pigeons as the cause, they realized they’d discovered the cosmic microwave background, the Big Bang’s afterglow. 17. See for yourself: Tune an old analog TV to an empty channel. Much of that “snow” is from the cosmic microwave background. 18. Gamma ray telescopes can detect light from the most violent explosions in the universe, probably caused by stars collapsing into black holes. If a gamma ray burst occurred within 6,000 light-years of us, we’d all be fried. 19. Weirdest telescope ever? In the 1960s physicist Raymond Davis Jr. used 100,000 gallons of dry-cleaning fluid to detect invisble neutrino particles as they stream from the sun. 20. Davis’s bizarre telescope worked, revealing fundamental new physics and netting him a Nobel in 2002. How Your Brain Can Control TimeHow Your Brain Can Control Time
The three methods your mind uses to reverse, speed, and even slow the minutes. by Carl Zimmer
Whenever I lose my watch, I take my sweet time to get a new one. I savor the freedom from my compulsion to carve my days into minute-size fragments. But my liberty has its limits. Even if I get rid of the clock strapped to my wrist, I cannot escape the one in my head. The human brain keeps time, from the flicker of milliseconds to the languorous unfurling of hours and days and years. It’s the product of hundreds of millions of years of evolution. Keeping track of time is essential for perceiving what’s happening around us and responding to it. In order to tell where a voice is coming from, we time how long it takes for the sound to reach both ears. And when we respond to the voice by speaking ourselves, we need precise timing to make ourselves understood. Our muscles in the mouth, tongue, and throat must all twitch in carefully timed choreography. It’s just a brief pause that makes the difference between “Excuse me while I kiss the sky” and “Excuse me while I kiss this guy.” Scientists are finding that telling time is also important to animals. At the University of Edinburgh, researchers built fake flowers with sugar inside to reveal how hummingbirds tell time. After hummingbirds drink nectar from real flowers, it takes time for the flowers to replenish their supply. The Scottish researchers refilled some of their fake flowers every 10 minutes and others every 20. Hummingbirds quickly learned just how long they had to wait before coming back to each kind. Scientists at the University of Georgia have discovered that rats do an excellent job of telling time too. They can be conditioned to wait two days after a meal to poke their noses into a trough and be rewarded with food. For 40 years, psychologists thought that humans and animals kept time with a biological version of a stopwatch. Somewhere in the brain, a regular series of pulses was being generated. When the brain needed to time some event, a gate opened and the pulses moved into some kind of counting device. One reason this clock model was so compelling: Psychologists could use it to explain how our perception of time changes. Think about how your feeling of time slows down as you see a car crash on the road ahead, how it speeds up when you’re wheeling around a dance floor in love. Psychologists argued that these experiences tweaked the pulse generator, speeding up the flow of pulses or slowing it down. Staring at an angry face for five seconds feels longer than staring at a neutral one. But the fact is that the biology of the brain just doesn’t work like the clocks we’re familiar with. Neurons can do a good job of producing a steady series of pulses. They don’t have what it takes to count pulses accurately for seconds or minutes or more. The mistakes we make in telling time also raise doubts about the clock models. If our brains really did work that way, we ought to do a better job of estimating long periods of time than short ones. Any individual pulse from the hypothetical clock would be a little bit slow or fast. Over a short time, the brain would accumulate just a few pulses, and so the error could be significant. The many pulses that pile up over long stretches of time should cancel their errors out. Unfortunately, that’s not the case. As we estimate longer stretches of time, the range of errors gets bigger as well. CLICK CLOCK Dean Buonomano, a neuroscientist at UCLA, argues that in order to perceive time in fractions of a second, our brains tell time as if they were observing ripples on a pond. Let’s say you are listening to a chirping bird. Two of its chirps are separated by a tenth of a second. The first chirp triggers a spike of voltage in some auditory neurons, which in turn causes some other neurons to fire as well. The signals reverberate among the neurons for about half a second, just as it takes time for the ripples from a rock thrown into a pond to disappear. When the second chirp comes, the neurons have not yet settled down. As a result, the second chirp creates a different pattern of signals. Buonomano argues that our brains can compare the second pattern to the first to tell how much time has passed. The brain needs no clock because time is encoded in the way neurons behave. Whenever I lose my watch, I take my sweet time to get a new one. I savor the freedom from my compulsion to carve my days into minute-size fragments. But my liberty has its limits. Even if I get rid of the clock strapped to my wrist, I cannot escape the one in my head. The human brain keeps time, from the flicker of milliseconds to the languorous unfurling of hours and days and years. It’s the product of hundreds of millions of years of evolution. Keeping track of time is essential for perceiving what’s happening around us and responding to it. In order to tell where a voice is coming from, we time how long it takes for the sound to reach both ears. And when we respond to the voice by speaking ourselves, we need precise timing to make ourselves understood. Our muscles in the mouth, tongue, and throat must all twitch in carefully timed choreography. It’s just a brief pause that makes the difference between “Excuse me while I kiss the sky” and “Excuse me while I kiss this guy.” Scientists are finding that telling time is also important to animals. At the University of Edinburgh, researchers built fake flowers with sugar inside to reveal how hummingbirds tell time. After hummingbirds drink nectar from real flowers, it takes time for the flowers to replenish their supply. The Scottish researchers refilled some of their fake flowers every 10 minutes and others every 20. Hummingbirds quickly learned just how long they had to wait before coming back to each kind. Scientists at the University of Georgia have discovered that rats do an excellent job of telling time too. They can be conditioned to wait two days after a meal to poke their noses into a trough and be rewarded with food. For 40 years, psychologists thought that humans and animals kept time with a biological version of a stopwatch. Somewhere in the brain, a regular series of pulses was being generated. When the brain needed to time some event, a gate opened and the pulses moved into some kind of counting device. One reason this clock model was so compelling: Psychologists could use it to explain how our perception of time changes. Think about how your feeling of time slows down as you see a car crash on the road ahead, how it speeds up when you’re wheeling around a dance floor in love. Psychologists argued that these experiences tweaked the pulse generator, speeding up the flow of pulses or slowing it down. Staring at an angry face for five seconds feels longer than staring at a neutral one. But the fact is that the biology of the brain just doesn’t work like the clocks we’re familiar with. Neurons can do a good job of producing a steady series of pulses. They don’t have what it takes to count pulses accurately for seconds or minutes or more. The mistakes we make in telling time also raise doubts about the clock models. If our brains really did work that way, we ought to do a better job of estimating long periods of time than short ones. Any individual pulse from the hypothetical clock would be a little bit slow or fast. Over a short time, the brain would accumulate just a few pulses, and so the error could be significant. The many pulses that pile up over long stretches of time should cancel their errors out. Unfortunately, that’s not the case. As we estimate longer stretches of time, the range of errors gets bigger as well. CLICK CLOCK Dean Buonomano, a neuroscientist at UCLA, argues that in order to perceive time in fractions of a second, our brains tell time as if they were observing ripples on a pond. Let’s say you are listening to a chirping bird. Two of its chirps are separated by a tenth of a second. The first chirp triggers a spike of voltage in some auditory neurons, which in turn causes some other neurons to fire as well. The signals reverberate among the neurons for about half a second, just as it takes time for the ripples from a rock thrown into a pond to disappear. When the second chirp comes, the neurons have not yet settled down. As a result, the second chirp creates a different pattern of signals. Buonomano argues that our brains can compare the second pattern to the first to tell how much time has passed. The brain needs no clock because time is encoded in the way neurons behave. If Buonomano turns out to be right, he will have explained only our fastest time telling, because after half a second, the brain’s ripples dissipate. On the scale of seconds to hours, the brain must use some other strategy. Warren Meck of Duke University argues that the brain measures long stretches of time by producing pulses. But the brain does not then count the pulses in the way a clock does. Instead, Meck suspects, it does something more elegant. It listens to the pulses as if they were music. It’s possible that we reverse time in our memories in order to focus our brains on goals. Meck first began to develop his musical model when he discovered how to rob rats of their perception of time. He had only to destroy certain clumps of neurons deep inside the brain. Some of these neurons, known as medium spiny neurons, are unlike any other neurons in the brain. Each one is linked to as many as 30,000 other neurons. And those linked neurons can be found throughout the cortex, the outer rind of the brain that handles much of the brain’s most sophisticated information processing. Certain neurons come from regions that handle vision, others from areas that apply rules to what we perceive, and so on. By receiving so many signals from all over the brain, Meck believes, the medium spiny neurons give us a sense of time. Imagine you are listening to a 10-second tone. At the beginning of the tone, neurons around your cortex reset themselves, so that they all begin to fire in sync. But some fire faster than others, and so at any moment some are active and some are quiet. From one moment to the next, a medium spiny neuron receives a unique pattern of signals from the neurons that link to it. The pattern changes like chords on a piano. When the 10 seconds are over, the medium spiny neuron can simply “listen” to the chord to tell how much time has passed. Meck has found support for his model by recording the electrical activities of neurons and in other researchers’ studies on people with a skewed sense of time. Certain neurotransmitters, such as dopamine, control pulsing neurons. Drugs such as cocaine and methamphetamine alter the brain by flooding it with dopamine, and studies have shown that they also change the second-to-second perception of time. In one experiment at UCLA, reported in 2007, scientists rang a bell after 53 seconds of silence. Healthy people estimated on average that 67 seconds had passed. Stimulant addicts guessed 91 seconds. Other drugs have the opposite effect on dopamine and compress the subjective experience of time. IN REAL TIME Recently, Hunt had people stare straight ahead with a ticking clock off to one side. She asked people to move their eyes over to the clock and make a note of the time when they had done so. On average, they reported seeing the clock about four hundredths of a second before their eyes actually arrived there. Moving time backward may actually serve us well, by letting us cope with an imperfect nervous system. Each of our retinas has a small patch of densely packed, light-sensitive cells called the fovea. In order to get a detailed picture of our surroundings, we have to jerk our eyes around several times a second so that the fovea can scan them. On its own, this stream of signals from our eyes would produce a jarring series of jump cuts. Our brains manufacture the illusion of a seamless flow of reality. In the course of that editing, we may need to fudge the time line—both in anticipation of an event and after the fact. But the most radical reworking of time may come as we inscribe it in our memories. We recall not just what happened but when. We can recall how much time has passed since an event occurred by tapping into our memories. Injuries and surgeries that destroy a particular part of the brain can give some hints about how the brain records time in memory. French scientists in 2007 reported their study of a group of patients who had suffered damage to a region known as the left temporal lobe. The patients watched a documentary, and a familiar object appeared on the screen, then reappeared a few minutes later. The patients had to guess how much time had passed. On average, the patients thought an 8-minute period was roughly 13. (Normal subjects were off by only about a minute.) These experiments are helping scientists zero in on the regions of the brain that store memories of time. Exactly how those regions record time is still mysterious. It’s one thing to listen in on the brain’s music, recognizing chords that mark the passage of five minutes. But how do the brain’s memory-related neurons then archive those five minutes so that they can be recalled later? FILE-SAVE, FILE-OPEN As it stores time in memories, the brain may alter it in another way that is even more radical. It may record time so that our brains recall events in backward order. Scientists at MIT discovered reverse memories in an experiment on rats. They had rats run down a track and then stop to eat food at the end. When rats (and humans) become more familiar with a place, individual neurons start becoming active when the rats reach particular spots. The scientists identified “place cells” that fired when the rats moved to different spots along the track. When the rats stopped to eat, the scientists eavesdropped on their brains again. They heard the place neurons fire again—probably as the memories of the track were becoming stronger in the rat brain. But the place neurons at the end of the track fired first, and the ones at the beginning of the track fired last. It’s possible that we reverse time in our memories in order to focus our brains on goals (for the MIT rats, the goal was the food at the end of the track). We are not free from time, in other words, but we are not its slaves. We stretch and twist it to serve our own needs. Time, in other words, is just a tool. Tutankhamen Fathered Twins, Mummified Fetuses SuggestTutankhamen Fathered Twins, Mummified Fetuses SuggestScienceDaily (Sep. 4, 2008) — Two fetuses found in the tomb of Tutankhamen may have been twins and were very likely to have been the children of the teenage Pharaoh, according to the anatomist who first studied the mummified remains of the young King in the 1960s. Replica of King Tutankhamen bust. (Credit: iStockphoto/Greg Nicholas)
Robert Connolly, who is working with the Egyptian authorities to analyse the mummified remains of Tutankhamen and the two stillborn children, will discuss the new findings at the Pharmacy and Medicine in Ancient Egypt Conference at The University of Manchester on September 1, 2008. Mr Connolly says: "The work carried out by Catherine Hellier in Norway and I suggests that the two fetuses in the tomb of Tutankhamen could be twins despite their very different size and thus fit better as a single pregnancy for his young wife. This increases the likelihood of them being Tutankhamen's children. "I studied one of the mummies, the larger one, back in 1979, determined the blood group data from this baby mummy and compared it with my 1969 blood grouping of Tutankhamen. The results confirmed that this larger fetus could indeed be the daughter of Tutankhamen. "Now we believe that they are twins and they were both his children. The forthcoming DNA study on them by Dr Zahi Hawass's group in Egypt will contribute another key piece to this question." Mr Connolly, Senior Lecturer in Physical Anthropology at the University of Liverpool's Department of Human Anatomy and Cell Biology, adds: "It is a very exciting finding which will not only paint a more detailed picture of this famous young King's life and death, it will also tell us more about his lineage." More than 100 delegates from 10 countries, including the Director of the Cultural Bureau of the Egyptian Embassy in the UK and researchers from Egypt's Conservation of Medicinal Plants project in Sinai and the British Museum, are attending the conference, hosted by the KNH Centre for Biomedical Egyptology at The University of Manchester, in conjunction with the National Research Centre in Cairo, Egypt, and sponsored by The Leverhulme Trust. |
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