By Tia Ghose Blocking a death receptor causes damaged myelin, the protective coating surrounding nerve cells, to repair itself, according to a study published Sunday (July 3) in Nature Medicine. The finding suggests that drugs targeting the receptor could help treat multiple sclerosis by reversing the myelin damage characteristic of the disease. “Showing remyelination, as they do in vivo and in vitro, is a pretty cool result,” said Richard Ransohoff, a Cleveland Clinic neuroscientist who was not involved in the work. The new receptor is a novel first step in potentially repairing damaged nerves of multiple sclerosis patients, he said. Current multiple sclerosis drugs slow the disease’s progression by quieting the inflammatory response of the immune system, which attacks the myelin surrounding nerve cells and kills oligodendrocytes, brain cells that make and repair myelin. Without their myelin, nerve cells gradually lose their ability to send electrical signals. But because they suppress the immune response, these drugs make patients more susceptible to rare infections such as viral brain inflammation and diseases such as leukemia. They also cannot undo existing damage, leading scientists to seek out approaches that stimulate the growth of new myelin or the restoration of existing myelin. Though research has identified several candidate molecules that promote myelin survival, none have yet proven to do so successfully in patients. © 1986-2011 The Scientist

Keyword: Multiple Sclerosis; Apoptosis
Link ID: 15532 - Posted: 07.07.2011

By Nathan Seppa A nutritional supplement that is free of charge, offers a wide range of health benefits and poses little risk sounds like fodder for a late-night TV commercial. But proponents of vitamin D are increasingly convinced that the sunshine vitamin delivers the goods, no strings attached. It offers a safe route to better health, these advocates say, by promoting proper function of the bones, heart, brain, immune system, you name it. Yet, the proponents claim, most people don’t get enough. Whereas humans’ pre­historic ancestors lived outdoors and made oodles of vitamin D in their sun-exposed skin, people today have become shut-ins by comparison — and scant sun exposure means low vitamin D. Of course, not everyone sees such a grand reach for the vitamin. While scientists concur that it is essential for bone maintenance, some stop right there. The skeptics note that vitamin D’s other promising qualities have shown up largely in studies that fall short of the gold standard of medicine — the randomized controlled trial, in which groups of people get either a placebo or the real thing. While a handful of randomized trials have shown additional benefits, others have not, leaving a gap in the vitamin’s otherwise sterling reputation. This debate came to a head last November, when an Institute of Medicine panel of scientists announced new vitamin D recommendations. The old intake levels were barely high enough to prevent rickets, a bone condition associated with the Industrial Revolution. The IOM panel boosted the recommended daily intake of the vitamin from 200 to 600 international units per day for most of the population. The new dose is about 15 micrograms, in the range of vitamin D found in most multivitamins. © Society for Science & the Public 2000 - 2011

Keyword: Parkinsons; Hormones & Behavior
Link ID: 15531 - Posted: 07.05.2011

Rowan Hooper, news editor Poor old Carolyn. Six of her previous babies have been taken away from her, and, as this film opens, men are coming to take her seventh. Her son, a chimpanzee named Nim, is two weeks old and is about to be transplanted from his birthplace at a primate research centre in Oklahoma into - wait for it - a large brownstone on the upper west side of Manhattan. There he will live with a human family and be raised as a human child. Thus begins the stranger than fiction true story that's explored in James Marsh's new documentary, Project Nim. What on earth were they thinking of? Nim was put in diapers and dressed in clothes. He was breastfed by his human surrogate mother, Stephanie Lafarge. "It seemed natural," she says. Lafarge's daughter, Jenny Lee, has a better explanation: "It was the seventies". Jenny was 10-years-old when Nim came to live with her family. The film, assembled from archive footage shot at the time, recreated scenes and interviews with the main characters, tells the story of Nim's chaotic life. In the mid 1970s a scientific debate was raging over the origin of language. There were two camps: those who held that human language was part of a continuum, in which case we'd expect other primates to have the rudiments of language, and those who thought language was uniquely human and there would be no evolutionary trace of it in other apes. © Copyright Reed Business Information Ltd.

Keyword: Language; Evolution
Link ID: 15530 - Posted: 07.05.2011

By NATALIE ANGIER Among the Ache hunter-gatherers in eastern Paraguay, healthy adults with no dependent offspring are expected to donate as much as 70 to 90 percent of the food they forage to the needier members of the group. And as those strapping suppliers themselves fall ill, give birth or grow old, they know they can count on the tribe to provide. Among the !Kung bushmen of the Kalahari in Africa, a successful hunter who may be inclined to swagger is kept in check by his compatriots through a ritualized game called “insulting the meat.” You asked us out here to help you carry that pitiful carcass? What is it, some kind of rabbit? Among the Hadza foragers of northern Tanzania, people confronted by a stingy food sharer do not simply accept what’s offered. They hold out their hand, according to Frank Marlowe, an anthropologist at Durham University in England, “encouraging the giver to keep giving until the giver finally draws the line.” Among America’s top executives today, according to a study commissioned by The New York Times, the average annual salary is about $10 million and rising some 12 percent a year. At the same time, the rest of the tribe of the United States of America struggles with miserably high unemployment, stagnant wages and the worst economic crisis since the Great Depression. Now, maybe the wealth gap is a temporary problem, and shiny new quarters will soon rain down on us all. But if you’re feeling tetchy and surly about the lavished haves when you have not a job, if you’re tempted to go out and insult a piece of corporate meat, researchers who study the nature and evolution of human social organization say they are hardly surprised. © 2011 The New York Times Company

Keyword: Evolution
Link ID: 15529 - Posted: 07.05.2011

By PAM BELLUCK People in a large area of the American South have long been known to have more strokes and to be more likely to die from them than people living elsewhere in the country. Now, a large national study suggests the so-called stroke belt may have another troubling health distinction. Researchers have found that Southerners there also are more likely to experience a decline in cognitive ability over several years — specifically, problems with memory and orientation. The differences to date in the continuing study are not large: Of nearly 24,000 participants, 1,090 in eight stroke-belt states showed signs of cognitive decline after four years, compared with 847 people in 40 other states. But the geographic difference persisted even after the researchers adjusted for factors — like age, sex, race and education — that might influence the result. The most recent data from the study were published in Annals of Neurology. None of the people with cognitive decline in the study had had detectable strokes. But some experts believe their memory problems and other mental issues could be related to the same underlying risk factors, including lifestyle patterns that contribute to hypertension, high cholesterol, diabetes and obesity. Is it the fried food beloved by Southerners? Limited access to doctors? Too little exercise? Researchers are investigating those and other possible causes. Some experts also suggest that the participants could have had small, undetectable strokes that subtly affected brain function. © 2011 The New York Times Company

Keyword: Stroke; Learning & Memory
Link ID: 15528 - Posted: 07.05.2011

By LAURA BEIL Just as the ear has two purposes — hearing and telling you which way is up — so does the eye. It receives the input necessary for vision, but the retina also houses a network of sensors that detect the rise and fall of daylight. With light, the body sets its internal clock to a 24-hour cycle regulating an estimated 10 percent of our genes. The workhorse of this system is the light-sensitive hormone melatonin, which is produced by the body every evening and during the night. Melatonin promotes sleep and alerts a variety of biological processes to the approximate hour of the day. Light hitting the retina suppresses the production of melatonin — and there lies the rub. In this modern world, our eyes are flooded with light well after dusk, contrary to our evolutionary programming. Scientists are just beginning to understand the potential health consequences. The disruption of circadian cycles may not just be shortchanging our sleep, they have found, but also contributing to a host of diseases. “Light works as if it’s a drug, except it’s not a drug at all,” said George Brainard, a neurologist at Thomas Jefferson University in Philadelphia and one of the first researchers to study light’s effects on the body’s hormones and circadian rhythms. Any sort of light can suppress melatonin, but recent experiments have raised novel questions about one type in particular: the blue wavelengths produced by many kinds of energy-efficient light bulbs and electronic gadgets. © 2011 The New York Times Company

Keyword: Biological Rhythms; Vision
Link ID: 15527 - Posted: 07.05.2011

By BENEDICT CAREY Researchers have long known that the brain links all kinds of new facts, related or not, when they are learned about the same time. Just as the taste of a cookie and tea can start a cascade of childhood memories, as in Proust, so a recalled bit of history homework can bring to mind a math problem — or a new dessert — from that same night. For the first time, scientists have recorded traces in the brain of that kind of contextual memory, the ever-shifting kaleidoscope of thoughts and emotions that surrounds every piece of newly learned information. The recordings, taken from the brains of people awaiting surgery for epilepsy, suggest that new memories of even abstract facts — an Italian verb, for example — are encoded in a brain-cell firing sequence that also contains information about what else was happening during and just before the memory was formed, whether a tropical daydream or frustration with the Mets. The new study suggests that memory is like a streaming video that is bookmarked, both consciously and subconsciously, by facts, scenes, characters and thoughts. Experts cautioned that the new report falls well short of revealing how contextual memory and different cues interact; some words might throw the mind into a vivid reverie, while others do not. But the report does provide a glimpse into how the brain places memories in space and time. “It’s a demonstration of this very cool idea that you have remnants of previous thoughts still rattling around in your head, and you bind the representation of what’s happening now to the fading embers of those old thoughts,” said Ken Norman, a neuroscientist at Princeton who did not participate in the study. “I think they have very good evidence that this process is crucial to time-stamping your memories.” © 2011 The New York Times Company

Keyword: Learning & Memory
Link ID: 15526 - Posted: 07.05.2011

By Stephanie Pappas It's hard to eat just one potato chip, and a new study may explain why. Fatty foods like chips and fries trigger the body to produce chemicals much like those found in marijuana, researchers report today (July 4) in the journal Proceedings of the National Academy of Sciences (PNAS). These chemicals, called "endocannabinoids," are part of a cycle that keeps you coming back for just one more bite of cheese fries, the study found. "This is the first demonstration that endocannabinoid signaling in the gut plays an important role in regulating fat intake," study researcher Daniele Piomelli, a professor of pharmacology at the University of California, Irvine, said in a statement. The study found that fat in the gut triggers the release of endocannabinoids in the brain, but the gray stuff between your ears isn't the only organ that makes natural marijuana-like chemicals. Human skin also makes the stuff. Skin cannabinoids may play the same role for us as they do for pot plants: Oily protection from the wind and sun. Endocannabinoids are also known to influence appetite and the sense of taste, according to a 2009 study in PNAS, which explains the munchies people get when they smoke marijuana. © 2011 LiveScience.com.

Keyword: Obesity; Drug Abuse
Link ID: 15525 - Posted: 07.05.2011

By LAURIE TARKAN A new study of twins suggests that environmental factors, including conditions in the womb, may be at least as important as genes in causing autism. The researchers did not say which environmental influences might be at work. But other experts said the new study, released online on Monday, marked an important shift in thinking about the causes of autism, which is now thought to affect at least 1 percent of the population in the developed world. “This is a very significant study because it confirms that genetic factors are involved in the cause of the disorder,” said Dr. Peter Szatmari, a leading autism researcher who is the head of child psychiatry and behavioral neuroscience at McMaster University in Ontario. “But it shifts the focus to the possibility that environmental factors could also be really important.” As recently as a few decades ago, psychiatrists thought autism was caused by a lack of maternal warmth. And while that notion has been discarded in favor of genetic explanations, there has been growing acceptance that genes do not tell the whole story, in part because autism rates appear to have increased far faster than our genes can evolve. “I think we now understand that both genetic and environmental factors have to be taken seriously,” said Dr. Joachim Hallmayer, an associate professor of psychiatry and behavioral sciences at Stanford and the lead author of the new study, which is to be published in the November issue of Archives of General Psychiatry. © 2011 The New York Times Company

Keyword: Autism; Genes & Behavior
Link ID: 15524 - Posted: 07.05.2011

by Sally Adee ROSALIND PICARD'S eyes were wide open. I couldn't blame her. We were sitting in her office at the Massachusetts Institute of Technology's Media Lab, and my questions were stunningly incisive. In fact, I began to suspect that I must be one of the savviest journalists she had ever met. Then Picard handed me a pair of special glasses. The instant I put them on I discovered that I had got it all terribly wrong. That look of admiration, I realised, was actually confusion and disagreement. Worse, she was bored out of her mind. I became privy to this knowledge because a little voice was whispering in my ear through a headphone attached to the glasses. It told me that Picard was "confused" or "disagreeing". All the while, a red light built into the specs was blinking above my right eye to warn me to stop talking. It was as though I had developed an extra sense. The glasses can send me this information thanks to a built-in camera linked to software that analyses Picard's facial expressions. They're just one example of a number of "social X-ray specs" that are set to transform how we interact with each other. By sensing emotions that we would otherwise miss, these technologies can thwart disastrous social gaffes and help us understand each other better. Some companies are already wiring up their employees with the technology, to help them improve how they communicate with customers. Our emotional intelligence is about to be boosted, but are we ready to broadcast feelings we might rather keep private? © Copyright Reed Business Information Ltd.

Keyword: Emotions; Robotics
Link ID: 15523 - Posted: 07.05.2011

by Michael Balter Most researchers regard language as unique to humans, something that makes our species special. But they fiercely debate how the ability to speak and listen evolved. Did speech require our species to evolve novel capabilities, or did we simply combine and enhance various abilities that other animals have, too? A new study with a language-trained chimp suggests that when it comes to understanding speech, the basic equipment might already have been present in our apelike ancestors. The notion that language evolved only in the human lineage and has no parallels in other animals has long been attributed to the linguist Noam Chomsky, who argued beginning in the 1960s that humans had a special "language organ" unique to us. But more recent studies have shown that other species are surprisingly good at communication, and many researchers have abandoned this idea—even Chomsky himself no longer holds to it strictly. However, some scientists continue to argue that humans have evolved unique ways to perceive and understand speech that allows us to use words as symbols for complex meanings. These contentions are based in part on a notable human talent: We can recognize words and understand entire sentences, even if the sounds of the words have been dramatically altered until they are a pale shadow of their linguistically meaningful selves. So a team of researchers turned to Panzee, a 25-year-old chimpanzee, to test the assumption that only humans have this talent. Humans raised Panzee from the age of 8 days, and her caregivers exposed her to a rich diet of English language conversation about food, people, objects, and events. Panzee can't talk, so she communicates with those around her using a lexigram board of symbols corresponding to English words (see photo). She can point to 128 different lexigrams when she hears the corresponding spoken word. © 2010 American Association for the Advancement of Science.

Keyword: Language; Evolution
Link ID: 15522 - Posted: 07.02.2011

By Jeannine Stamatakis I met Kim Peek when he gave a presentation at Ohlone College in October 2009, just a few weeks before his passing. During the talk, Peek astonished my students by showcasing his remarkable talent for calendar calculations. Just from knowing my students’ birth dates, Peek was able to determine the day of the week they were born and could recall the front-page news that day. Known as a mega savant or a “Kimputer,” Peek had one of the most impressive memories people have ever seen. Physicians who examined Peek discovered that he had damage to the cerebellum, a brain region that regulates attention and language, as well as emotional reactions, such as pleasure and fear. Perhaps most notably, physicians found that Peek had no corpus callosum, the bundle of nerves that connects the brain’s right and left hemispheres. They speculated that the absence of this critical structure allowed Peek’s neurons to make new and unusual connections between his right and left hemispheres. These novel connections most likely explain his abnormal memory capacity. According to Peek’s father, Peek could memorize every word in the books they read before he was two years old. Peek progressed to reading two pages simultaneously. Although how he did so remains a mystery, some have theorized he read the left page of a book with his left eye and the right page with his right eye. © 2011 Scientific American,

Keyword: Laterality; Learning & Memory
Link ID: 15521 - Posted: 07.02.2011

By Bob Roehr Chronic pain affects at least one in three adults in the U.S., which is more than the sum total of those with heart disease, cancer and diabetes combined. For many of these 116 million Americans, their pain is severe and eludes available treatments. In addition to the human suffering, the monetary cost of medical treatment and lost productivity has reached $635 billion a year. The U.S. needs "a cultural transformation" in the way we view pain, treat it and conduct research on its causes and treatments, says a new report released June 29 by the Institute of Medicine (IOM). Pain can be protective. Acute pain tells us to pull a finger back from a hot stove, stop walking on a blistered foot or allow a fevered body to rest. It is a warning that bodily injury needs attention and time to heal. But when the pain signal continues for an extended period, "it can become a disease in its own right," Philip Pizzo, dean of the Stanford University School of Medicine and chair of the committee that wrote the IOM report said at the news conference where the report was released. Pain can actually rewire nerve and brain pathways. In much the same way that memories are created, it can become a self-perpetuating loop that continues to feed back on itself long after the original cause for the pain has resolved. Chronic pain can shrink the volume of the brain's gray matter, the portion of the brain devoted to thought. Researchers speculate that this decrease results in part from a limited pattern of stimulation of circuits that are preoccupied with a continuous pain loop that crowds out other activity. In addition to that, continuously stimulating the pathway releases more of the neurotransmitter glutamate, an excess of which can be toxic. © 2011 Scientific American,

Keyword: Pain & Touch
Link ID: 15520 - Posted: 07.02.2011

Sandrine Ceurstemont, video producer It's a well-known effect typically experienced when looking at a waterfall: after staring at a moving scene, stationary objects seem to pulse in the opposite direction when you look away. You can experience the illusion in this video by fixing your eyes on a pattern that moves inwards. When the static image of a bee suddenly appears, it seems to expand. Since it was first documented by Aristotle, the effect has puzzled scientists. Does our brain consciously adapt to a moving scene or is it a subconscious response? Now Davis Glasser and his team from the University of Rochester have gained insight by showing people supershort videos of a moving pattern. They found that the illusion occurs even after watching a scene for a fraction of a second, proving that it's a subconscious response. The team also identified the neurons responsible for the effect, located in an area of the visual cortex involved in motion perception. So it seems that this illusion isn't down to a perceptual oddity but rather the result of a fundamental process that occurs every time we look at moving objects. But according to Glasser, the strength of the effect depends on the amount of time spent looking at a pattern. "In the video above, you're adapting for 30 seconds or more, so the effect is very strong," he says. "You can see illusory motion in almost anything you look at, whether it's the bee that pops up on the screen, or other objects around the room." After watching the short videos in the study, the sensation was much weaker. Journal reference: PNAS, DOI: 10.1073/pnas.1101141108 © Copyright Reed Business Information Ltd.

Keyword: Vision
Link ID: 15519 - Posted: 07.02.2011

By Bruce Bower Babies snooze through much of the first month after birth, but don’t call them lazy. One-month-olds doze to discover, with an emphasis on social insights, a new study suggests. Snoozing infants learned to blink in response to three types of sounds, says psychologist Bethany Reeb-Sutherland of the University of Maryland, College Park, and her colleagues. Sleeping babies blinked more readily upon hearing a spoken voice than a tone or a recorded voice played backward, signaling an early aptitude for absorbing social information, the researchers report in a paper published online June 18 in Developmental Science. “Although young infants spend much of their time sleeping, they continue to learn about the environment around them, particularly the social environment,” Reeb-Sutherland says. These findings help to explain how infants come to recognize speech sounds within several months of birth, remarks psychologist Carolyn Rovee-Collier of Rutgers University in Piscataway, N.J. “From birth through at least 1 month of age, infants learn while they sleep — an ability that adults lack,” Rovee-Collier says. Sleep bolsters memories and decision making in adults (SN: 4/28/07, p. 260), but no evidence suggests that slumbering grown-ups can learn new information. © Society for Science & the Public 2000 - 2011

Keyword: Language; Development of the Brain
Link ID: 15518 - Posted: 07.02.2011

Canadian and U.S. researchers have been able to predict what hand movement a person is going to make by reading a scan of their brain. The scientists at the University of Western Ontario and the University of Oregon scanned the brains of nine volunteers at the Robarts Research Institute in London, Ont. They found they were able to distinguish somewhat accurately among plans to make three hand movements that were only slightly different from one another: Jody Culham and Jason Gallivan at the University of Western Ontario were the two lead authors of the study. Jody Culham and Jason Gallivan at the University of Western Ontario were the two lead authors of the study. (University of Western Ontario)"We're showing that you can decode little subtle differences in finger movements based on the goal of the movement," said Jason Gallivan, a Ph.D. student in neuroscience at the University of Western Ontario and the lead author of a study published in the Journal of Neuroscience this week. Previously, scientists had only been able to make similar predictions for animals with electrodes inserted in their brains. Funcational magnetic resonance imaging, or fMRI, is far less intrusive, said Jody Culham, a psychology professor at the University of Western Ontario who is Gallivan’s supervisor and co-author. That made it possible to do such an experiment in humans. While the new discovery may bring to mind Minority Report, the 2002 movie starring Tom Cruise where criminals are caught before the crimes they commit, Gallivan said that type of scenario is a long way off. © CBC 2011

Keyword: Robotics
Link ID: 15517 - Posted: 07.02.2011

By Janet Raloff An ingredient in many clear plastics also renders some gender-linked behaviors plastic, at least in mice. Two new studies link feminized behaviors in adult males with exposures during development to bisphenol A, a weak estrogen-mimicking chemical. In one study, some behaviors in BPA-exposed females morphed into features characteristic of males. The findings come from laboratory studies conducted in different species. Each experiment also exposed animals at a different time during development — one from the womb through weaning, the other during the rodent equivalent of adolescence and early adulthood. The trials therefore identify different periods during which the brain appears vulnerable to pollutants that mimic or alter the activity of sex hormones. Because early BPA exposures left no lasting changes in sex hormone levels, the authors of each study note, the behavioral changes they observed in adulthood probably trace to an earlier rewiring of brain circuitry — most likely in an area known as the hippocampus. Cheryl Rosenfeld of the University of Missouri–Columbia and her colleagues added BPA to the chow they fed to pregnant deer mice. BPA concentrations in the moms peaked at around 9 nanograms per milliliter, Rosenfeld says, “which is in the range of what’s been measured in humans.” © Society for Science & the Public 2000 - 2011

Keyword: Sexual Behavior; Neurotoxins
Link ID: 15516 - Posted: 06.30.2011

By Tina Hesman Saey The high-risk version of a gene associated with Alzheimer’s disease hinders the brain’s ability to clear out a troublesome protein, a new study finds. Researchers have known that people who carry the e4 version of the gene APOE are at higher risk for Alzheimer’s disease and more likely to have cell-killing plaques in their brains than people who have the e3 or e2 versions. But it hasn’t been clear whether people with the e4 version made more of the plaque protein — called amyloid-beta — or if the stuff just stuck around in their brains longer. Now researchers led by David Holtzman of the Washington University School of Medicine in St. Louis have directly measured levels of amyloid-beta in the brain fluid of mice. The measurements, reported in the June 29 Science Translational Medicine, show that mice with the e4 version of APOE make amyloid-beta at the same rate and in the same amount as mice with different versions of the gene, but don’t clear the protein out of their brains as efficiently. The study will probably draw more attention to the role amyloid-beta clearance plays in Alzheimer’s disease, says Caleb Finch, a neurobiologist and codirector of the Alzheimer Disease Research Center at the University of Southern California. “I think this is a valuable contribution,” he says. It is not yet clear how different forms of the protein made by APOE govern clearance of amyloid-beta from the brain, says Joseph Castellano, a neuroscientist working in Holtzman’s lab. “We don’t understand that at all,” he says. © Society for Science & the Public 2000 - 2011

Keyword: Alzheimers
Link ID: 15515 - Posted: 06.30.2011

by Jessica Hamzelou Those who find optical illusions easy to solve might be less inclined to ask themselves why. It seems the human brain may have a trade-off between processing visual information and introspection. Chen Song and her colleagues at University College London found last year that people with more grey matter in the primary visual cortex were better at solving visual illusions. The team has now looked for size differences elsewhere in the brain that correlate with variation in the visual cortex. They used a functional MRI scanner to build a map of the primary visual cortex of 30 volunteers while also capturing a structural image of their brains. Running the images through a computer, Song was surprised to find a relationship between the primary visual cortex and a region at the front of the brain called the anterior prefrontal cortex (aPFC). "When people have a bigger anterior prefrontal cortex, they have a smaller visual cortex, and vice versa," she says. Previous research has shown that the size of the aPFC is linked to introspection – individuals with more grey matter in this brain region are better able to assess whether they made the right decision. Song's study suggests that more introspective individuals forego finer aspects of visual perception. The team will now carry out behavioural studies to find out if this is the case. © Copyright Reed Business Information Ltd.

Keyword: Attention; Vision
Link ID: 15514 - Posted: 06.30.2011

by Michael Marshall If you've ever wondered what crows are saying when they caw at a perceived threat from the treetops, here is a sample: "I'm telling on you!" By watching who their neighbours and parents scold, one group of crows has learned to recognise and scold a dubious human. John Marzluff of the University of Washington in Seattle discovered five years ago that crows can recognise individual humansMovie Camera who posed a threat. He briefly trapped American crows (Corvus brachyrhynchos) on his university's campus while wearing a distinctive "caveman" mask. Afterwards, crows that had been trapped scolded anyone they spotted wearing the caveman mask, following them around and cawing harshly, but studiously ignored people wearing a neutral mask. Since then Marzluff has been monitoring the birds' response to the masks. Tests in which researchers toured the campus wearing masks showed that more and more crows had taken to scolding people sporting the caveman mask. Two weeks after the trapping, 26 per cent of crows scolded people wearing the offending mask, but 2.7 years later a remarkable 66 per cent did so. In the fifth year of the study, Marzluff barely got 50 metres out of his office in the caveman mask before a mob of crows started scolding him. The behaviour also gradually spread outwards from the original trapping site. © Copyright Reed Business Information Ltd

Keyword: Animal Communication; Language
Link ID: 15513 - Posted: 06.30.2011