By George Johnson The mystery of whether there is a natural resonance between music and our brains, as I mentioned in a post last week, brings up an even deeper question: whether mathematics itself is neurologically innate, giving the mind (or some minds) direct access to the structure of the universe. Thinking about that recently led me back to one of Oliver Sack’s most astonishing essays. It appeared in his collection The Man Who Mistook His Wife for a Hat, and is about two twins, idiot savants who appeared to have an almost supernatural ability to quickly tell if a number is prime. Prime numbers are those that cannot be broken down into factors — smaller numbers that can be multiplied together to produce the larger one. They have been described as the atoms of the number system. 11 and 13 are obviously prime while 12 and 14 are not. But with larger numbers our brains are quickly flummoxed. Is 7244985277 prime? I just typed the digits by twitching my fingers along the top row of my keyboard. To test the number by hand I would have to start at the beginning of the number system and begin trying out the possible divisors. There are shortcuts to avoid testing every single one. We know 2 can’t be a factor since 7244985277, like all primes, is odd. For the same reason we can rule out all even factors. And you only have to test factors up to the square root of a number. (The factors of 100 are 2 x 50, 4 x 25, 5 x 20, and 10 x 10. Testing beyond 10 would be redundant.)

Keyword: Miscellaneous
Link ID: 17847 - Posted: 02.26.2013

By Meghan Rosen Mouse brain cells scamper close to eternal life: They can actually outlive their bodies. Mouse neurons transplanted into rat brains lived as long as the rats did, surviving twice as long as the mouse’s average life span, researchers report online February 25 in the Proceedings of the National Academy of Sciences. The findings suggest that long lives might not mean deteriorating brains. “This could absolutely be true in other mammals — humans too,” says study author Lorenzo Magrassi, a neurosurgeon at the University of Pavia in Italy. The findings are “very promising,” says Carmela Abraham, a neuroscientist at Boston University. “The question is: Can neurons live longer if we prolong our life span?” Magrassi’s experiment, she says, suggests the answer is yes. One theory about aging, Magrassi says, is that every species has a genetically determined life span and that all the cells in the body wear out and die at roughly the same time. For the neurons his team studied, he says, “We have shown that this simple idea is certainly not true.” Magrassi’s team surgically transplanted neurons from embryonic mice with an average life span of 18 months into rats. To do so, the researchers slipped a glass microneedle through the abdomens of anesthetized pregnant mice. Then, using a dissecting microscope and a tool to illuminate the corn-kernel-sized mouse embryos, the researchers scraped out tiny bits of brain tissue and injected the neurons into fetal rat brains. After the rat pups were born, Magrassi and colleagues waited as long as three years, until the animals were near death, to euthanize the rats and dissect their brains. © Society for Science & the Public 2000 - 2013

Keyword: Stem Cells; Development of the Brain
Link ID: 17846 - Posted: 02.26.2013

By Athena Andreadis Genes are subject to multiple layers of regulation. An early regulatory point is transcription. During this process, regulatory proteins bind to DNA regions (promoters and enhancers) that direct gene expression. These DNA/protein complexes attract the transcription apparatus, which docks next to the complex and proceeds linearly downstream, producing the heteronuclear (hn) RNA that is encoded by the gene linked to the promoter. The hnRNA is then spliced and either becomes structural/regulatory RNA or is translated into protein. Transcription factors are members of large clans that arose from ancestral genes that went through successive duplications and then diverged to fit specific niches. One such family of about fifty members is called FOX. Their DNA binding portion is shaped like a butterfly, which has given this particular motif the monikers of forkhead box or winged helix. The activities of the FOX proteins extend widely in time and region. One of the FOX family members is FOXP2, as notorious as Fox News – except for different reasons: FOXP2 has become entrenched in popular consciousness as “the language gene”. As is the case with all such folklore, there is some truth in this; but as is the case with everything in biology, reality is far more complex. FOXP2, the first gene found to “affect language” (more on this anon), was discovered in 2001 by several converging observations and techniques. The clincher was a large family (code name KE), some of whose members had severe articulation and grammatical deficits with no accompanying sensory or cognitive impairment. The inheritance is autosomal dominant: one copy of the mutated gene is sufficient to confer the trait. When the researchers definitively identified the FOXP2 gene, they found that the version of FOXP2 carried by the KE affected members has a single point mutation that alters an invariant residue in its forkhead domain, thereby influencing the protein’s binding to its DNA targets. © 2013 Scientific American

Keyword: Language; Sexual Behavior
Link ID: 17845 - Posted: 02.25.2013

By James Gallagher Health and science reporter, BBC News A part of the brain's ability to shield itself from the destructive damage caused by a stroke has been explained by researchers. It has been known for more than 85 years that some brain cells could withstand being starved of oxygen. Scientists, writing in the journal Nature Medicine, have shown how these cells switch into survival mode. They hope to one-day find a drug which uses the same trick to protect the whole brain. Treating a stroke is a race against time. Clots that block the blood supply prevent the flow of oxygen and sugar to brain cells, which then rapidly die. But in 1926, it was noticed that some cells in the hippocampus, the part of the brain involved in memory, did not follow this rule. "They're staying alive when the prediction would say that they should die," said Prof Alastair Buchan from Oxford University who has investigated how they survive. I'm a survivor Experiments on rats showed that these surviving-cells started producing a protein called hamartin - which forces cells to conserve energy. They stop producing new proteins and break down existing ones to access the raw materials. When the researchers prevented the cells from producing hamartin, they died just like other cells. BBC © 2013

Keyword: Stroke
Link ID: 17844 - Posted: 02.25.2013

By MICHAEL MOSS On the evening of April 8, 1999, a long line of Town Cars and taxis pulled up to the Minneapolis headquarters of Pillsbury and discharged 11 men who controlled America’s largest food companies. Nestlé was in attendance, as were Kraft and Nabisco, General Mills and Procter & Gamble, Coca-Cola and Mars. Rivals any other day, the C.E.O.’s and company presidents had come together for a rare, private meeting. On the agenda was one item: the emerging obesity epidemic and how to deal with it. While the atmosphere was cordial, the men assembled were hardly friends. Their stature was defined by their skill in fighting one another for what they called “stomach share” — the amount of digestive space that any one company’s brand can grab from the competition. James Behnke, a 55-year-old executive at Pillsbury, greeted the men as they arrived. He was anxious but also hopeful about the plan that he and a few other food-company executives had devised to engage the C.E.O.’s on America’s growing weight problem. “We were very concerned, and rightfully so, that obesity was becoming a major issue,” Behnke recalled. “People were starting to talk about sugar taxes, and there was a lot of pressure on food companies.” Getting the company chiefs in the same room to talk about anything, much less a sensitive issue like this, was a tricky business, so Behnke and his fellow organizers had scripted the meeting carefully, honing the message to its barest essentials. “C.E.O.’s in the food industry are typically not technical guys, and they’re uncomfortable going to meetings where technical people talk in technical terms about technical things,” Behnke said. “They don’t want to be embarrassed. They don’t want to make commitments. They want to maintain their aloofness and autonomy.” A chemist by training with a doctoral degree in food science, Behnke became Pillsbury’s chief technical officer in 1979 and was instrumental in creating a long line of hit products, including microwaveable popcorn. He deeply admired Pillsbury but in recent years had grown troubled by pictures of obese children suffering from diabetes and the earliest signs of hypertension and heart disease. In the months leading up to the C.E.O. meeting, he was engaged in conversation with a group of food-science experts who were painting an increasingly grim picture of the public’s ability to cope with the industry’s formulations — from the body’s fragile controls on overeating to the hidden power of some processed foods to make people feel hungrier still. It was time, he and a handful of others felt, to warn the C.E.O.’s that their companies may have gone too far in creating and marketing products that posed the greatest health concerns. © 2013 The New York Times Company

Keyword: Drug Abuse; Obesity
Link ID: 17843 - Posted: 02.25.2013

by Andy Coghlan Deep brain stimulation helps some people with obsessive-compulsive disorder (OCD), but no one was quite sure why it is effective. A new study offers an explanation: the stimulation has surprisingly pervasive effects, fixing abnormal signalling between different parts of the brain. A small number of people with difficult-to-treat OCD have had electrodes permanently implanted deep within their brain. Stimulating these electrodes reduces their symptoms. To work out why stimulation has this effect, Damiaan Denys and Martijn Figee at the Academic Medical Center in Amsterdam, the Netherlands, and colleagues recorded neural activity in people with electrodes implanted into a part of the brain called the nucleus accumbens. This region is vital for conveying motivational and emotional information to the frontal cortex to guide decisions on what actions to take next. In some people with OCD, feedback loops between the two get jammed, leading them to do the same task repeatedly to reduce anxiety. Surplus signalling The researchers took fMRI scans as participants rested. In 13 people with OCD and implanted electrodes, there was continuous and excessive exchange of signals between the nucleus accumbens and the frontal cortex that was not seen in 11 control subjects. When the electrodes were activated, though, the neural activity of both brain regions in the people with OCD became virtually identical to that in the controls. © Copyright Reed Business Information Ltd

Keyword: OCD - Obsessive Compulsive Disorder
Link ID: 17842 - Posted: 02.25.2013

—By Chris Mooney It is still considered highly uncool to ascribe a person's political beliefs, even in part, to that person's biology: hormones, physiological responses, even brain structures and genes. And no wonder: Doing so raises all kinds of thorny, non-PC issues involving free will, determinism, toleration, and much else. There's just one problem: Published scientific research keeps going there, with ever increasing audacity (not to mention growing stacks of data). The past two weeks have seen not one but two studies published in scientific journals on the biological underpinnings of political ideology. And these studies go straight at the role of genes and the brain in shaping our views, and even our votes. First, in the American Journal of Political Science, a team of researchers including Peter Hatemi of Penn State University and Rose McDermott of Brown University studied the relationship between our deep-seated tendencies to experience fear—tendencies that vary from person to person, partly for reasons that seem rooted in our genes—and our political beliefs. What they found is that people who have more fearful disposition also tend to be more politically conservative, and less tolerant of immigrants and people of races different from their own. As McDermott carefully emphasizes, that does not mean that every conservative has a high fear disposition. "It's not that conservative people are more fearful, it's that fearful people are more conservative," as she puts it.

Keyword: Emotions
Link ID: 17841 - Posted: 02.25.2013

An international team of biologists has successfully identified some of the brain chemicals that may help clarify some unanswered questions about how humans sleep. The research - conducted by the University of California, Los Angeles (UCLA) and the University of Toronto - focused on seals and the chemicals found in their brain, as they are able to sleep with half their brain at a time. Professor John Peever of the University of Toronto said: "Seals do something biologically amazing - they sleep with half their brain at a time. The left side of their brain can sleep while the right side stays awake. Seals sleep this way while they're in water, but they sleep like humans while on land. Our research may explain how this unique biological phenomenon happens." The study's first author, PhD student Jennifer Lapierre, measured how the brain chemicals change while the seals are asleep and awake. She found that acetylcholine - an important brain chemical - was at low levels on the sleeping side of the brain, but high levels on the waking side. This discovery suggests that acetylcholine may be responsible for brain alertness. They also discovered - to their surprise - that the chemical serotonin was present in both sides of the brain whether the seal was awake or asleep. It was previously thought that serotonin caused brain arousal. Researchers hope that the discovery of the chemicals may make a breakthrough in understanding and curing sleeping disorders. The study's senior author, Jerome Siegel from UCLA's Brain Research Institute added: "Understanding which brain chemicals function to keep us awake or asleep is a major scientific advance. It could help solve the mystery of how and why we sleep." © independent.co.uk

Keyword: Sleep
Link ID: 17840 - Posted: 02.23.2013

by Julia Sklar IT IS a nightmare situation. A person diagnosed as being in a vegetative state has an operation without anaesthetic because they cannot feel pain. Except, maybe they can. Alexandra Markl at the Schön clinic in Bad Aibling, Germany, and colleagues studied people with unresponsive wakefulness syndrome (UWS) – also known as vegetative state – and identified activity in brain areas involved in the emotional aspects of pain. People with UWS can make reflex movements but can't show subjective awareness. There are two distinct neural networks that work together to create the sensation of pain. The more basic of the two – the sensory-discriminative network – identifies the presence of an unpleasant stimulus. It is the affective network that attaches emotions and subjective feelings to the experience. Crucially, without the activity of the emotional network, your brain detects pain but won't interpret it as unpleasant. Using PET scans, previous studies have detected activation in the sensory-discriminative network in people with UWS but their findings were consistent with a lack of subjective awareness, the hallmark of the condition. Now Markl and her colleagues have found evidence of activation in the affective or emotional network too (Brain and Behavior, doi.org/kfs). © Copyright Reed Business Information Ltd.

Keyword: Consciousness; Pain & Touch
Link ID: 17839 - Posted: 02.23.2013

Regina Nuzzo Say the word 'rutabaga', and you have just performed a complex dance with many body parts — lips, tongue, jaw and larynx — in a flash of time. Yet little is known about how the brain coordinates these vocal-tract movements to keep even the clumsiest of us from constantly tripping over our own tongues. A study of unprecedented detail now provides a glimpse into the neural codes that control the production of smooth speech. The results help to clarify how the brain uses muscles to organize sounds and hint at why tongue twisters are so tricky. The work is published today in Nature1. Most neural information about the vocal tract has come from watching people with brain damage or from non-invasive imaging methods, neither of which provide detailed data in time or space2, 3. A team of US researchers has now collected brain-activity data on a scale of millimetres and milliseconds. The researchers recorded brain activity in three people with epilepsy using electrodes that had been implanted in the patients' cortices as part of routine presurgical electrophysiological sessions. They then watched to see what happened when the patients articulated a series of syllables. Sophisticated multi-dimensional statistical procedures enabled the researchers to sift through the huge amounts of data and uncover how basic neural building blocks — patterns of neurons firing in different places over time — combine to form the speech sounds of American English. The patterns for consonants were quite different from those for vowels, even though the parts of speech “use the exact same parts of the vocal tract”, says author Edward Chang, a neuroscientist at the University of California, San Francisco. © 2013 Nature Publishing Group

Keyword: Language
Link ID: 17838 - Posted: 02.23.2013

by Sara Reardon Like the musicians in an orchestra, our lips, tongue and vocal cords coordinate with one another to pronounce sounds in speech. A map of the brain regions that conduct the process shows how each is carefully controlled – and how mistakes can slip into our speech. It's long been thought that the brain coordinates our speech by simultaneously controlling the movement of these "articulators". In the 1860s, Alexander Melville Bell proposed that speech could be broken down in this way and designed a writing system for deaf people based on the principle. But brain imaging had not had the resolution to see how neurons control these movements – until now. Using electrodes implanted in the brains of three people to treat their epilepsy, Edward Chang and his colleagues at the University of California mapped brain activity in each volunteer's motor cortex as they pronounced words in American English. The team had expected that each speech sound would be controlled by a unique collection of neurons, and so each would map to a different part of the brain. Instead, they found that the same groups of neurons were activated for all sounds. Each group controls muscles in the tongue, lips, jaw and larynx. The neurons – in the sensorimotor cortex – coordinated with one another to fire in different combinations. Each combination resulted in a very precise placing of the articulators to generate a given sound. Surprisingly, although each articulator can theoretically take on an almost limitless range of shapes, the neurons imposed strict limits on the range of possibilities. © Copyright Reed Business Information Ltd.

Keyword: Language
Link ID: 17837 - Posted: 02.23.2013

By ANAHAD O'CONNOR Depression may lower the effectiveness of the shingles vaccine, a new study found. The research showed that adults with untreated depression who received the vaccine mounted a relatively weak immune response. But those who were taking antidepressants showed a normal response to the vaccine, even when symptoms of depression persist. Shingles, an acute and painful rash, strikes a million Americans each year, mostly older adults. Health officials recommend that those over 60 get vaccinated against the condition, which is caused by reactivation of the same virus that causes chickenpox, varicella-zoster. In the new study, published in the journal Clinical Infectious Diseases, researchers followed a group of 92 older men and women for two years. Forty of the subjects had a major depressive disorder; they were matched with 52 control subjects of similar age. The researchers measured their immune responses to the shingles vaccine and a placebo shot. Compared with the control patients, those with depression were poorly protected by the vaccine. But the patients who were being treated for their depression showed a boost in immunity — what the researchers called a “normalization” of the immune response. It is unclear why that was the case. The authors of the study speculated that treatment of older people with depression might increase the effectiveness of the flu shot and other vaccines as well. Copyright 2013 The New York Times Company

Keyword: Depression; Neuroimmunology
Link ID: 17836 - Posted: 02.23.2013

By Janet Raloff Hospitals rush newborns into a neonatal intensive care unit when those babies are struggling to survive. Although NICUs offer tender and vigilant care, many of the devices they rely on can expose their tiny patients to a relatively large dose of a hormone-mimicking pollutant, bisphenol A. Newborns in intensive care excrete BPA, on average, at levels of around 17.8 micrograms per liter — well above the 0.45 µg/l typical of healthy infants, researchers report in the March Pediatrics. One of the most reliable indicators of BPA exposure was the level of care that a baby received, reflected by the number of devices used to deliver that care, notes nurse and exposure-science researcher Susan Duty of Simmons College in Boston. Breathing tubes, intravenous drug delivery lines and enclosed incubators are plastic, and several types of plastic can contain BPA. Although researchers have not figured out what doses of BPA cause toxicity in people, several studies have linked elevated prenatal exposures to later behavioral problems (SN Online: 7/16/12) and moodiness (SN: 11/7/09, p. 12) in young children. Animal studies have also linked BPA exposure during development to feminization in males and risks of later hypertension and diabetes. Duty’s team studied 55 infants, each of whom spent at least three days in a NICU in the Boston area, and most of whom had been born prematurely or were for other reasons very small. The researchers measured BPA in the breast milk and formula that these tiny babies consumed. Both nutritional sources had small, comparable amounts of BPA. © Society for Science & the Public 2000 - 2013

Keyword: Development of the Brain; Neurotoxins
Link ID: 17835 - Posted: 02.23.2013

Sandrine Ceurstemont, editor, New Scientist TV It's the sequel to fertilisation: the brains of unborn babies have now been imaged in action, showing how connections form. This fMRI movie, produced by Moriah Thomason from Wayne State University in Detroit, Michigan, shows a fly-through of several fetuses in their third trimester. By comparing the scans at slightly different stages of development, Thomason was able to pinpoint when different parts of the brain wire up. "The connection strength increases with fetal age," writes Thomason. By identifying how brain connectivity normally develops, the scans could help diagnose and treat conditions like schizophrenia and autism before birth. For more on this research, read our full-length news story, "First snaps made of fetal brains wiring themselves up". © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain; Brain imaging
Link ID: 17834 - Posted: 02.23.2013

Canadian researchers have found out how to restore normal vision to kittens with a lazy eye without using an eye patch. The cure was relatively simple — putting the kittens in complete darkness for 10 days. Once the kittens were returned to daylight, they regained normal vision in the lazy eye within a week, reported researchers at Dalhousie University in Halifax in the journal Current Biology this month. Lazy eye is a condition where the brain effectively turns off one eye. It affects about four per cent of the population in humans, and the most common treatment is fix the vision problem (for example, by using glasses) and then patch the good eye, forcing the person to use their bad eye. Kevin Duffy, a neuroscientist who co-authored the new study, told CBC's Quirks & Quarks that the condition is typically the result of a vision problem such as a cataract, a misalignment of the eyes, or poor focus in one eye, which then causes the brain to develop abnormally. "If the eye is providing abnormal vision, then the circuits that connect to that eye are going to develop abnormally," he said. The brain "becomes effectively disconnected." © CBC 2013

Keyword: Vision; Development of the Brain
Link ID: 17833 - Posted: 02.23.2013

By Susan Milius Slight electric fields that form around flowers may lure pollinators much as floral colors and fragrances do. In lab setups, bumblebees learned to distinguish fake flowers by their electrical fields, says sensory biologist Daniel Robert at the University of Bristol in England. Combining an electrical charge with a color helped the bees learn faster, Robert and his colleagues report online February 21 in Science. Plants, a bit like lightning rods, tend to conduct electrical charges to the ground, Robert says. And bees pick up a positive charge from the atmosphere’s invisible rain of charged particles. “Anything flying through the air, whether it’s a baseball, 767 jumbo jet, or a bee, acquires a strong positive electrostatic charge due to interaction with air molecules,” says Stephen Buchmann of the University of Arizona in Tucson. Robert and his colleagues checked whether bees could choose flowers based solely on the electric fields the plants produce. Purple metal disks (encased in plastic so as not to shock bees) stood in for flowers. Half of them, wired for 30 volts, held sips of sugar water. The unwired ones offered a bitter quinine solution that bees don’t like. Bombus terrestris bumblebees learned to choose sweet, wired disks more than 80 percent of the time. When researchers unplugged the wired disks, the bees bumbled, scoring sugar only by chance. © Society for Science & the Public 2000 - 2013

Keyword: Vision
Link ID: 17832 - Posted: 02.23.2013

By Tina Hesman Saey Like the sun, insulin levels rise and fall in a daily rhythm. Disrupting that cycle may contribute to obesity and diabetes, a new study suggests. Many body systems follow a daily clock known as a circadian rhythm. Body temperature, blood pressure and the release of many hormones are on circadian timers. But until now, no one had shown that insulin — a hormone that helps control how the body uses sugars for energy — also has a daily cycle. Working with mice, researchers at Vanderbilt University in Nashville have found that rodents are more sensitive to insulin’s effects at certain times of day. Disrupting the animals’ circadian timers interferes with the hormone’s daily rise and fall and makes mice prone to obesity. If the findings hold up in humans, they could help explain why people who work night shifts tend to be overweight and suffer health problems. The discovery may also tie the obesity epidemic in part to staying up late and eating at the wrong time. Many people had thought that it was best for the body to maintain insulin at a relatively constant level, says Carl Johnson, a circadian biologist who led the new study. “But that’s not how organisms have adapted,” he says. Since the environment cycles through light and dark, body processes often coordinate with that rhythm. To uncover insulin’s natural rhythm, Johnson and his colleagues performed an “insulin clamp” procedure on mice. The clamp infuses glucose or insulin around the clock into mice that are moving freely in their cages. Measuring how much insulin or glucose the mice need to maintain constant blood sugar levels tells the researchers how responsive the animals are to the hormone at any given time of day. © Society for Science & the Public 2000 - 2013

Keyword: Biological Rhythms; Obesity
Link ID: 17831 - Posted: 02.23.2013

by Michael Balter Despite recent progress toward sexual equality, it's still a man's world in many ways. But numerous studies show that when it comes to language, girls start off with better skills than boys. Now, scientists studying a gene linked to the evolution of vocalizations and language have for the first time found clear sex differences in its activity in both rodents and humans, with the gene making more of its protein in girls. But some researchers caution against drawing too many conclusions about the gene's role in human and animal communication from this study. Back in 2001, the world of language research was rocked by the discovery that a gene called FOXP2 appeared to be essential for the production of speech. Researchers cautioned that FOXP2 is probably only one of many genes involved in human communication, but later discoveries seemed to underscore its importance. For example, the human version of the protein produced by the gene differs by two amino acids from that of chimpanzees, and seems to have undergone natural selection since the human and chimp lineages split between 5 million and 7 million years ago. (Neandertals were found to have the same version as Homo sapiens, fueling speculation that our evolutionary cousins also had language). In the years since, FOXP2 has been implicated in the vocalizations of other animals, including mice, singing birds, and even bats. During this same time period, a number of studies have confirmed past research suggesting that young girls learn language faster and earlier than boys, producing their first words and sentences sooner and accumulating larger vocabularies faster. But the reasons behind such findings are highly controversial because it is difficult to separate the effects of nature versus nurture, and the differences gradually disappear as children get older. © 2010 American Association for the Advancement of Science

Keyword: Language; Sexual Behavior
Link ID: 17830 - Posted: 02.20.2013

by Virginia Morell Every bottlenose dolphin has its own whistle, a high-pitched, warbly "eeee" that tells the other dolphins that a particular individual is present. Dolphins are excellent vocal mimics, too, able to copy even quirky computer-generated sounds. So, scientists have wondered if dolphins can copy each other's signature whistles—which would be very similar to people saying each others' names. Now, an analysis of whistles recorded from hundreds of wild bottlenose dolphins confirms that they can indeed "name" each other, and suggests why they do so—a discovery that may help researchers translate more of what these brainy marine mammals are squeaking, trilling, and clicking about. "It's a wonderful study, really solid," says Peter Tyack, a marine mammal biologist at the University of St. Andrews in the United Kingdom who was not involved in this project. "Having the ability to learn another individual's name is … not what most animals do. Monkeys have food calls and calls that identify predators, but these are inherited, not learned sounds." The new work "opens the door to understanding the importance of naming." Scientists discovered the dolphins' namelike whistles almost 50 years ago. Since then, researchers have shown that infant dolphins learn their individual whistles from their mothers. A 1986 paper by Tyack did show that a pair of captive male dolphins imitated each others' whistles, and in 2000, Vincent Janik, who is also at St. Andrews, succeeded in recording matching calls among 10 wild dolphins "But without more animals, you couldn't draw a conclusion about what was going on," says Richard Connor, a cetacean biologist at the University of Massachusetts, Dartmouth. Why, after all, would the dolphins need to copy another dolphin's whistle? © 2010 American Association for the Advancement of Science

Keyword: Language; Evolution
Link ID: 17829 - Posted: 02.20.2013

Stephen S. Hall Male sexual dysfunction is never pretty, even in nematodes. In normal roundworm courtship, a slender male will sidle up to a plump hermaphrodite, make contact, and then initiate a set of steps leading up to insemination: a sinuous backwards motion as he searches for the sexual cleft, a pause to probe, and finally the transfer of sperm. The whole business is usually over in a couple of minutes. “It's very slithery, and affectionate,” says Cornelia Bargmann, who has been observing the behaviour of this particular worm, Caenorhabditis elegans, for 25 years. Last October, scientists in Bargmann's laboratory at the Rockefeller University, New York, reported the discovery of a gene that seems to be crucial to successful mating. Disrupting the action of this gene causes male sexual confusion of almost epic pathos: nematodes with certain mutations poke tentatively at an inert hermaphrodite, making confused, fruitless curlicues around the potential mate. Occasionally the mutant male succeeds, but often he literally falls off the job and begins the search anew for a mate. Jennifer Garrison, a postdoc of Bargmann's who tracked the behaviour of these males, just shakes her head as she replays the scene on her computer screen. “Really sad,” she says. There are two punchlines to this story of thwarted invertebrate mating. One is the charming squeamishness with which Bargmann describes it, hesitating at words such as “vulva” and “spicule” and other anatomical gewgaws of roundworm reproduction. “As a well-brought-up Southern girl,” she says with a laugh, “it's still difficult to talk about this!” © 2013 Nature Publishing Group

Keyword: Genes & Behavior; Development of the Brain
Link ID: 17828 - Posted: 02.20.2013