by Andy Coghlan Scans of the brains of child musicians before and after musical training have yielded compelling evidence that proficiency and skill relies on hard graft, not innate genius. Earlier studies have shown that adult musicians have different brains to adult non-musicians. But the latest results settle arguments about whether the brain differences were there from birth, or developed through practice. "This is the first paper showing differential brain development in children who learned and played a musical instrument versus those that did not," says Gottfried Schlaug of Harvard Medical School. Schlaug's team tested musically untrained six-year-olds from the Boston area, 15 of whom then received weekly keyboard lessons for 15 months, and 16 of whom didn't. When they compared magnetic resonance imaging (MRI) scans taken before and after for both groups, they found that auditory and motor areas of the brain linked respectively with hearing and dexterity grew larger only in the trainee musicians. At the end of the training period, the musicians also outperformed the others at specific tasks related to manual dexterity and discrimination of sounds. But the two groups were matched on more distantly related skills such as arithmetic. Schlaug says that the same pupils are being followed in case it takes longer for these more "distant" skills to emerge. © Copyright Reed Business Information Ltd.

Keyword: Hearing; Learning & Memory
Link ID: 12648 - Posted: 06.24.2010

Your fingertips are among the most sensitive parts of your body, and this makes them surprisingly easy to fool. Take an ordinary comb and pencil and lay your index finger along the top of the comb, then run the pencil back and forth along the side of the teeth. Even though the teeth are moving from side to side in a wave-like motion, your finger will feel as if a raised dot is travelling up and down the comb. According to Hayward, this works because the unfamiliar motion of the teeth causes similar skin deformation to the more usual action of running your finger over a raised bump, so your brain interprets it that way. Another way to fool your fingertips is to cut up a Post-it note and glue parts of it to the back of a card as shown in the diagrams (right). Now close your eyes and run your fingertip along the thin central strips. You will probably feel a raised ridge or depressed trough, even though the surface of the reassembled Post-it notes is perfectly flush. This illusion relies on the fact that your finger slides more freely along the non-sticky area, causing skin deformations that are exactly like those when touching a ridge or trough. Your tongue is also very sensitive, and it can be fooled in a similar way. Take a fork and press the tip of your tongue between the prongs. You will feel as though the middle two prongs are bent out of shape. This is because the skin on your tongue is distorted in a way that doesn't normally happen, so your brain assumes that the prongs, not your tongue, are bent. © Copyright Reed Business Information Ltd

Keyword: Pain & Touch
Link ID: 12647 - Posted: 06.24.2010

By Laura Sanders Harry Potter had it easy: All he had to do to see another wizard’s memories was peer into that wizard’s swirling pensieve. Mind-reading is not so simple for everybody else. But a new study reveals that even those without magical gadgets may one day “see” someone else’s memories. In the study, which appears online March 12 in Current Biology, researchers used patterns of brain activity to accurately predict where someone was standing in a virtual room. Each of four study participants sat down to a computer and toured a large virtual room. The room contained objects that helped volunteers get oriented, including clocks, chairs and pictures. As participants navigated through the virtual space, brain cells preserved the memory of the route taken to the final location (“turn left at the picture of the boat”). Once participants reached their destinations, they stared at blank virtual floor for five seconds. Only then did the researchers measure brain activity with fMRI, to ensure that the measured brain activity stemmed from the memories of getting to the location and not from thoughts associated with any particular object in the virtual room. “Because the floor was identical at each target location, then the only thing we could have been decoding was the spatial location,” explains Eleanor Maguire of University College London, a coauthor of the study. © Society for Science & the Public 2000 - 2009

Keyword: Learning & Memory; Brain imaging
Link ID: 12646 - Posted: 06.24.2010

By Haley Stephenson The bad memories instilled by a car accident or other traumatic event are best forgotten. That might soon be possible, now that researchers have identified neurons in mice that store fearful memories and have found a way to wipe these memories clean. Fearful memories are housed within a region of the brain called the lateral amygdala (LA). When something scary happens, LA neurons produce higher levels of a protein called CREB (cyclic adenosine monophosphate response element-binding protein). Previous studies have erased fear memories by blocking enzyme action in this brain region (ScienceNOW, 23 October 2008), however this study took another approach. Scientists suspected the CREB-making neurons were doing the actual "remembering" of fear, acting as the key to removing fearful memories, so they decided to destroy them and see what happened. First, Sheena Josselyn, a neuroscientist at the University of Toronto in Canada and colleagues put mice through fear training. When a tone played, the mice received an electrical shock to their feet. After several rounds, the mice froze in fear at the sound. Then the team flipped a genetically engineered switch that killed CREB-making neurons. When the researchers played the tone again 2, 5, even 12 days later, the mice didn't freeze--they forgot their fear. No other memories seemed to be affected, the team reports tomorrow in Science. The mice could store new memories, such as how to find cheese in a maze, and even relearn the foot-shock fear response, but only with training. Even when researchers killed a random assortment of LA neurons, fear-memory formation remained intact. "By destroying specific neurons, instead of deleting an entire brain region, our findings show for the first time which neurons store a [fearful] memory," says neuroscientist and co-author Jin-Hee Han of the University of Toronto. © 2009 American Association for the Advancement of Science

Keyword: Learning & Memory; Emotions
Link ID: 12645 - Posted: 06.24.2010

By Tina Hesman Saey Plants do shift work too. Researchers have now discovered an important worker on the second shift. Jose Pruneda-Paz, Steve A. Kay and their colleagues at the University of California, San Diego report in the March 13 Science that they have found a missing link in plants’ circadian clocks. A regulatory protein called CHE connects a morning cycle to an evening cycle. Daily rhythms in plants, animals and microorganisms are governed by circadian clocks. Even though the clocks keep time in much the same way, the genes and proteins that make up the gears differ. Scientists are still uncovering all the gears of plants’ clocks. Plants have a large number of regulatory proteins, called transcription factors, which wind the clock and keep it running on time. These transcription factors are organized in multiple feedback loops that help make timing more precise, Kay says. People used to think of the circadian clock as a simple circle, but no more. “All of a sudden it’s turned into something that looks like the Olympic flag, multiple interlocking loops,” Kay says. Scientists previously discovered that the morning shift in plants is governed by a protein known as CCA1, and the night shift is under control of TOC1. But researchers didn’t know who punched the clock on the second shift. © Society for Science & the Public 2000 - 2009

Keyword: Biological Rhythms
Link ID: 12644 - Posted: 06.24.2010

Burning the candle at both ends during the working week could raise a person's risk of developing type 2 diabetes, New York researchers say. People who slept fewer than six hours a night were more likely to develop a condition that precedes diabetes than those sleeping for longer, they found. They said the study supported mounting evidence that cutting back on sleep can have a profound impact on health. The six-year study was presented at a American Heart Association conference. Cases of type 2 diabetes, which are often, but not always, linked to obesity, have been rising across the globe. The condition develops when the body makes too much insulin, but does not use the hormone efficiently to break down sugar in the blood. A stepping stone on the way to the condition is known as impaired fasting glucose, in which blood sugar levels are too high, but not high enough to constitute a diagnosis of diabetes. A team from the University of Buffalo, in New York, followed a group of volunteers over a six-year period. They found those who slept on average for fewer than six hours a night during the working week were 4.56 times more likely to develop impaired fasting glucose than those sleeping six to eight hours a night. Lead researcher Dr Lisa Rafalson said: "This study supports growing evidence of the association of inadequate sleep with adverse health issues." Dr Rafalson said it was likely that hormones and the nervous system were behind the link. "Our findings will hopefully spur additional research into this very complex area of sleep and illness," she said. A recent study suggested that taking regular lunchtime siestas could increase the risk of developing type 2 diabetes. (C)BBC

Keyword: Sleep
Link ID: 12643 - Posted: 03.12.2009

By Gary Sherman and Gerald Clore When people are asked to list their favorite metaphor, they typically cite great works of poetry, literature or oratory. Indeed, many metaphors are born from creative insight—Romeo likening Juliet to the rising sun or poet Robert Burns comparing his love to a red rose. But there is more to metaphor than this. Some metaphors are not literary creations at all—instead they seem to be built from the ground up, given to us by experience. For example, knowledge—an intangible, abstract concept—is often recast in terms of the concrete experience of sight. To know something is to see it, and so we often say that we see someone’s point or that an idea is clear. Metaphors of this sort—linking the abstract to the concrete, perceptual, and visceral—were studied systematically by the UC-Berkley cognitive linguist George Lakoff and philosopher Mark Johnson, at Brown University. What they and others realized is that our concepts are fundamentally shaped by the fact that our minds reside in fleshy, physical bodies. As a result, even our most abstract concepts often have an “embodied” structure. In a classic example, people seem to understand moral virtue as if it were akin to physical cleanliness. To be virtuous is to be physically clean and free from the impurity that is sin. As the University of Pennsylvania psychologist and disgust expert Paul Rozin has shown, experiencing morality in terms of the embodied dimension of contagion can lead to some striking behaviors, such as the refusal to wear a sweater belonging to an evil person because it seems somehow contaminated by the evil essence of that person. © 1996-2009 Scientific American Inc.

Keyword: Emotions; Language
Link ID: 12642 - Posted: 06.24.2010

by Sunita Reed Wouldn’t it be amazing if researchers could scan our brains and see whether we have thrill seeking personality traits? Vanderbilt University psychologist David Zald has come pretty close. He has conducted a study that links thrill seeking behavior with a difference in specific part of the dopamine system in the brain. “Dopamine does a number of different things. Probably most importantly though it’s involved in motivation and reward,” explains Zald. “And it’s the critical chemical in terms of people really wanting to do things.” Specific brain cells, or neurons, make and release dopamine. When dopamine is released its target is specific dopamine receptors on other brain cells in the pleasure centers of the brain. There have been some studies of these receptors in people. But Zald wanted to look at a different structure on the dopamine releasing brain cells themselves, called autoreceptors, which function as brakes to stop the release of dopamine. Zald knew that studies in rodents showed that those with reduced brakes were more likely to explore in novel environments but were also more likely to self-administer cocaine or amphetamines. He also knew there was some limited evidence that individual differences in dopamine functioning was linked to novelty seeking. ©2009 ScienCentral

Keyword: Emotions; Brain imaging
Link ID: 12641 - Posted: 06.24.2010

by Aria Pearson THE first images to reveal the quality of the brain's wiring show that more aspects of intelligence are inherited than previously known. The finding hints at ways to boost intelligence. It is clear that intelligence is at least partly genetically determined. This was supported by the discovery in 2001 that the volume of the brain's grey matter, made up of "processor" cells, is heritable and correlates with certain elements of IQ (Nature Neuroscience, DOI: 10.1038/nn758). The amount of white matter, which provides the connections between these processors, has since been shown to be heritable too (Journal of Neuroscience, vol 26, p 10235). Now it seems that the quality of these connections, which is governed by the integrity of the protective myelin sheath that encases them, is also largely genetic, and correlates with IQ. Paul Thompson and colleagues at the University of California, Los Angeles, scanned the brains of 23 sets of identical twins and the same number of fraternal twins, using a type of magnetic resonance imaging called HARDI. MRI scans typically show the volumes of different tissues in the brain by measuring the amount of water present. HARDI measures the amount of water that is diffusing through white matter, a measure of the integrity of myelin sheathing, and therefore the speed of nerve impulses. "It's like a picture of your mental speed," says Thompson. © Copyright Reed Business Information Ltd

Keyword: Intelligence; Genes & Behavior
Link ID: 12640 - Posted: 06.24.2010

By Nathan Seppa Pregnant women who have one or more migraines also face a heightened risk of stroke and other vascular diseases, even during the pregnancy, a new study finds. Although strokes during a pregnancy are rare, women with a migraine listed on their medical chart face a 30-fold increase in the risk for the most common kind of stroke, researchers report online March 10 in the British Medical Journal. Pregnancy is actually a time when women who routinely contend with migraines are often free of them. “A lot of women have a wonderful kind of honeymoon away from migraines during pregnancy,” says study coauthor Cheryl Bushnell, a neurologist at Wake Forest University in Winston-Salem, N.C. Indeed, in a national database of more than 18 million women who were pregnant at some point from 2000 to 2003, Bushnell and her colleagues found only 33,965 women who had migraines listed on their medical charts upon discharge from the hospital — a rate well below the average. But when the researchers checked for other ailments on the charts, they found that women with migraines were 15 times as likely to have had a stroke listed on the chart, compared with women without migraines. The stroke could have occurred before or during pregnancy. What’s more, when counting only ischemic strokes, which account for the vast majority for all people, the risk rose to 30-fold. Ischemic strokes result when a blood clot blocks a vessel in the brain. © Society for Science & the Public 2000 - 2009

Keyword: Stroke; Hormones & Behavior
Link ID: 12639 - Posted: 06.24.2010

By Sara Coelho It's the nightmare of every parent: your child throws a tantrum in a crowded supermarket because you won't buy his or her favorite candy. But things could be worse. The crowd could start attacking you and your child. It turns out that's just what happens in one rhesus macaque society. When a mom doesn't give in to her baby's demands, it risks being smacked and bitten by its fellow monkeys. Rhesus monkey babies cry when they want to nurse. If a mother ignores her child for too long, the baby will begin flailing and screaming (see video). Curious about how monkey onlookers respond to these tantrums, primatologist Stuart Semple of Roehampton University in London and colleagues followed a wild troop of rhesus monkeys on Cayo Santiago, an island off the coast of Puerto Rico. For 4 months, Semple's team observed the interactions among 11 females, their young infants, and other members of the troop. Whether a baby got its way depended on who was around when it threw its tantrum. If the mothers were alone or only close relatives were nearby, the moms acquiesced to the baby's outbursts only about 40% to 50% of the time, the team reports online today in the Proceedings of the Royal Society B. But when highly aggressive macaques--those with a history of violence and those higher than the mother in the group's pecking order--were near, mothers gave in 82% of the time. "Bystanders affect the outcome of temper tantrums quite significantly," says Semple. © 2009 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Aggression
Link ID: 12638 - Posted: 06.24.2010

Jennifer Viegas -- A new study on the sleeping habits of walruses reveals that these flippered marine mammals are some of the world's most unusual snoozers, since they appear to sleep anywhere, but they may also break the world's record for continuously staying awake. Perhaps most unusual is their ability to sleep in various odd positions in the planet's ultimate waterbed -- the ocean. "In water, walruses slept while floating at the surface, lying on the bottom or standing and leaning," observed sleep expert Jerome Siegel and his colleagues. Walruses may also catch some shuteye by literally hanging out, since the researchers say the blubbery animals have been seen "resting in water while using their tusks to hang from ice floes." Siegel, director of the Center for Sleep Research at UCLA, and his team quietly viewed the behavior of Pacific female walruses previously caught in the Chukotka Sea and housed at the Utrish Marine Station of the Russian Academy of Sciences. According to the study, which has been accepted for publication in the journal Behavioral Brain Research, each walrus had its own seawater pool and resting platform. All were healthy, adapted to captivity and were fed fish and squid three times a day. A younger walrus was fed a liquid soymilk and fish formula. Siegel told Discovery News that when the walruses slept underwater, they could hold their breath for "about 4 to 5 minutes." Although the marine mammals experienced REM sleep while in water, it was fleeting. Any possible ocean-lulled dreams must be brief. © 2009 Discovery Communications, LLC

Keyword: Sleep; Evolution
Link ID: 12637 - Posted: 06.24.2010

Animal rights activists have claimed responsibility for the Saturday firebombing of a vehicle outside a UCLA neuroscience researcher's home, the Daily Bruin reports. No one was injured in the latest in a string against scientists who use animals in their research. There have been at least four firebombings since the beginning of 2008. On Monday, the North American Animal Liberation Press Office, which says it speaks on behalf of the activists, posted a statement on its website that threatened to continue to harass the targeted researcher until he stops his study. FBI and university police are still investigating the attack, and extra security has been placed at the home of the scientist, whose name is being withheld. So far, police say they have no leads, but they are offering a $445,000 reward for information leading to the arrests of individuals responsible for the various attacks on UCLA researchers. That includes $25,000 added after Saturday's attack. © 2009 U.S.News & World Report LP

Keyword: Animal Rights
Link ID: 12636 - Posted: 06.24.2010

LOS ANGELES - Brain surgery for weight loss? West Virginia mother of two Carol Poe, 60, is only the second person in the United States to undergo deep brain stimulation for weight loss after trying everything from diets to having her stomach stapled. Last month, she took part in a clinical trial at West Virginia University hospital in which neurosurgeons drilled into her brain and used electricity to control her feelings of hunger and satisfaction. Poe's story will be told on ABC Television's "Nightline" program on Monday, March 9. Poe, who is 5 feet 2 inches tall and who weighed 230 pounds before the surgery, said that at her heaviest she weighed about 490 pounds. Dr Julian Bailes, chairman of West Virginia University's department of neurosurgery, said Poe was a good candidate for the radical treatment. "This is not for overweight patients. It's for obese patients," Bailes told "Nightline." "This is a frontier of medicine...to be able to generate tiny pulses of electricity in these deep nuclei of the brain, and to see what effect they may have on behavior, including in this case the behavior of eating and the issue of uncontrolled appetite," he said. Bailes told Reuters that the West Virginia University hospital was the only one in the United States, and the only center he knew of worldwide, using the deep brain stimulation technique specifically on obese patients. Copyright 2009 Reuters

Keyword: Obesity
Link ID: 12635 - Posted: 03.10.2009

A group of German researchers may have figured out why a protein that can turn rogue and cause fatal illnesses such as mad cow disease exists in large quantities inside cows, humans and other animals. The protein — known as the "prion" protein or PrP — appears to help cells communicate with each other when an embryo is developing, said a paper published Monday in the journal PloS Biology by a group of researchers at University of Konstanz in Germany. "What we see PrP doing in the fish embryo … may be analogous to what it does in the mammalian brain, which is what may go wrong during prion diseases," biologist Edward Malaga-Trillo, who led the study, said in an email to CBCNews.ca. Diseases such as mad cow disease in cows and Creutzfeldt-Jakob disease in humans have been traced back to rogue, altered versions of the prion protein. But up until now, researchers have been unsure what normal versions of the protein are supposed to do. Those normal proteins are the "starting ingredient" for prion diseases. When prion proteins fold abnormally, they clump together into groups called plaques that lead to brain damage. The misfolded prions multiply by turning normal prions "bad." In previous studies, mice engineered so they were unable to produce the normal prion protein seemed mostly normal. However, in the recent study led by University of Konstanz biologist Edward Malaga-Trillo, zebrafish embryos that could not make the prion protein didn't develop normally and eventually died. © CBC 2009

Keyword: Prions
Link ID: 12634 - Posted: 06.24.2010

By PERRI KLASS, M.D. For a long time, children used to go to bed early, and not just in Proust. Think of Robert Louis Stevenson: In winter I get up at night And dress by yellow candle-light. In summer, quite the other way, I have to go to bed by day. I have to go to bed and see The birds still hopping on the tree. Well, not my children. Clearly, I did this wrong. When I read that Barack and Michelle Obama had set their daughters’ bedtime for 8 p.m., I asked my oldest (now 25) if he remembered having a bedtime when he was little. He just laughed at me. When he was a preschooler, I was a pediatric resident (before the limits on work hours), and evenings tended to start around 7 p.m. And mind you, these were 1980s evenings, free of e-mail and cellphones and texting and all the other distractions that make it harder and harder for a child — or an adult — to say goodnight. I’m not sure any of my three children ever had a regular bedtime before 9:30 or 10. Even at that, I’m afraid, we were pretty ad hoc: oh my, it’s almost 11 and the kid is still awake! Time to read him a story and put him to bed. Copyright 2009 The New York Times Company

Keyword: Sleep; Development of the Brain
Link ID: 12633 - Posted: 06.24.2010

Steve Connor A belief in God is deeply embedded in the human brain, which is programmed for religious experiences, according to a study that analyses why religion is a universal human feature that has encompassed all cultures throughout history. Scientists searching for the neural "God spot", which is supposed to control religious belief, believe that there is not just one but several areas of the brain that form the biological foundations of religious belief. The researchers said their findings support the idea that the brain has evolved to be sensitive to any form of belief that improves the chances of survival, which could explain why a belief in God and the supernatural became so widespread in human evolutionary history. "Religious belief and behaviour are a hallmark of human life, with no accepted animal equivalent, and found in all cultures," said Professor Jordan Grafman, from the US National Institute of Neurological Disorders and Stroke in Bethesda, near Washington. "Our results are unique in demonstrating that specific components of religious belief are mediated by well-known brain networks, and they support contemporary psychological theories that ground religious belief within evolutionary-adaptive cognitive functions." Scientists are divided on whether religious belief has a biological basis. Some evolutionary theorists have suggested that Darwinian natural selection may have put a premium on individuals if they were able to use religious belief to survive hardships that may have overwhelmed those with no religious convictions. Others have suggested that religious belief is a side effect of a wider trait in the human brain to search for coherent beliefs about the outside world. Religion and the belief in God, they argue, are just a manifestation of this intrinsic, biological phenomenon that makes the human brain so intelligent and adaptable. ©independent.co.uk

Keyword: Emotions
Link ID: 12632 - Posted: 06.24.2010

By JOHN TIERNEY Suppose last night you had two dreams. In one, God appears and commands you to take a year off and travel the world. In the other, God commands you to take a year off to go work in a leper colony. Which of those dreams, if either, would you consider meaningful? Or suppose you had one dream in which your friend defends you against enemies, and another dream in which that same friend goes behind your back and tries to seduce your significant other? Which dream would you take seriously? Tough questions, but social scientists now have answers — and really, it’s about time. For thousands of years, dreamers have had little more to go on than the two-gate hypothesis proposed in “The Odyssey.” After Penelope dreams of the return of her lost-long husband, she’s skeptical and says that only some dreams matter. “There are two gates,” she explains, “through which these unsubstantial fancies proceed; the one is of horn, and the other ivory. Those that come through the gate of ivory are fatuous, but those from the gate of horn mean something to those that see them.” Her two-gate hypothesis, later endorsed by Virgil and Ovid, was elegant in theory but not terribly useful in practice. How could you tell which gate your dream came from? One woman’s ivory could be another’s horn. Copyright 2009 The New York Times Company

Keyword: Sleep
Link ID: 12631 - Posted: 06.24.2010

by Linda Geddes Alcohol may taste sweeter if you were exposed to it before birth, suggests a study in rats. The findings may shed new light on why human studies have previously linked fetal alcohol exposure to increased alcohol abuse later in life, and to a lower age at which a person first starts drinking alcohol. Alcohol's taste is a mixture of sweet and bitter components. To test whether prenatal alcohol exposure could affect the perception of these components, Steven Youngentob at the State University of New York in Syracuse and John Glendinning at Columbia University in New York measured how avidly rats consumed ethanol, sweet water or bitter water. They found that young rats whose mothers had consumed alcohol during pregnancy preferred ethanol and consumed more of the bitter water than the offspring of mothers that didn't consume alcohol. Rats that had been exposed to alcohol in the uterus also seemed to be more attracted to the smell of alcohol. Prenatal exposure seems to reduce the perceived bitterness of alcohol, making it seem sweeter, says Youngentob. Both of these differences seemed to disappear once the rats reached adulthood – but only if they hadn't tasted alcohol during their youth. If prenatally exposed rats did consume alcohol in their youth, these preferences seemed to become set for life. © Copyright Reed Business Information Ltd.

Keyword: Drug Abuse; Development of the Brain
Link ID: 12630 - Posted: 06.24.2010

By Michael Balter In 1997, at the Furuvik Zoo in Gävle, Sweden, a male chimpanzee named Santino began throwing stones at zoo visitors. Although Santino was clearly agitated each time, as evidenced by his forceful stomping around the compound and hair standing on end, the chimp didn't just grab the first thing he saw and launch it. Rather, observations over the past decade have shown that Santino spends the mornings before the zoo opens gathering the stones and organizing them into neat piles as a sort of ammunition store. The chimp's preparation suggests that apes can plan for future mental states--in this case anger--a cognitive talent once thought to be unique to humans. Humans take planning for the future for granted. We shop for food even when we're not hungry, for example, because we know we will be hungry later. But until recently, scientists didn't know whether other animals thought ahead the same way. In the wild, many chimps use tools for procuring food, such as employing sticks to fish termites out of trees. But the apes tend to fashion the tools shortly before they are needed rather than far in advance. In the laboratory, on the other hand, carefully contrived experiments have shown that bonobos and orangutans can learn to choose and save the right tool that will later allow them to retrieve food. Yet these lab experiments do not prove that animals can anticipate future emotional states. That's where Santino comes in. Soon after the only other male chimp in his group died and he was left alone with four females, Santino began hurling stones at zoo visitors. Sometimes he'd let fly with a "hail storm" of 10 or more projectiles per attack, according to one zookeeper. Although no one was hurt, zoo workers had to warn the crowd to keep back and usher Santino into his chimp house. © 2009 American Association for the Advancement of Science.

Keyword: Evolution; Aggression
Link ID: 12629 - Posted: 06.24.2010