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By Hanae Armitage About 70 million people worldwide stutter when they speak, and it turns out humans aren’t the only ones susceptible to verbal hiccups. Scientists at this year’s Society for Neuroscience Conference in Chicago, Illinois, show that mice, too, can stumble in their vocalizations. In humans, stuttering has long been linked to a mutation in the “housekeeping” gene Gnptab, which maintains basic levels of cellular function. To cement this curious genetic link, researchers decided to induce the Gnptab “stutter mutation” in mice. They suspected the change would trigger a mouse version of stammering. But deciphering stuttered squeaks is no easy task, so researchers set up a computerized model to register stutters through a statistical analysis of vocalizations. After applying the model to human speech, researchers boiled the verbal impediment down to two basic characteristics—fewer vocalizations in a given period of time and longer gaps in between each vocalization. For example, in 1 minute, stuttering humans made just 90 vocalizations compared with 125 for non-stutterers. Using these parameters to evaluate mouse vocalizations, researchers were able to identify stuttering mice over a 3.5-minute period. As expected, the mice carrying the mutated gene had far fewer vocalizations, with longer gaps between “speech” compared with their unmodified littermates—Gnptab mutant mice had about 80 vocalizations compared with 190 in the nonmutant mice. The findings not only supply evidence for Gnptab’s role in stuttering, but they also show that its function remains relatively consistent across multiple species. Scientists say the genetic parallel could help reveal the neural mechanisms behind stuttering, be it squeaking or speaking. © 2015 American Association for the Advancement of Science.
Keyword: Language; Genes & Behavior
Link ID: 21527 - Posted: 10.20.2015
The invaders put on a disguise and infiltrate the nest with dark plans: to kill the queen and enslave the kingdom. Usually when ants take pupae from other colonies as future slaves all hell breaks loose in ensuing battles. The enslaved individuals sometimes even strike back against their overlords. It’s a relatively dramatic affair, usually resulting in the aggressive slave-makers carrying the pupae back to their own colony, says Terrence McGlynn at California State University. But a species of ant found in the eastern US, Temnothorax pilagens, does things differently. It is the first ant species known to waltz into a colony and enslave others without killing, and one of a few that take not only pupae but adult workers, too. “This was extremely surprising as ants are usually able to detect foreign species or even individuals from a different colony through their chemical profile and react aggressively towards them,” says Isabelle Kleeberg at Johannes Gutenberg-Universität Mainz, Germany, whose team has found how they get away with it. Kleeberg tracked the behaviour of T. pilagens and their preferred slave species, Temnothorax ambiguus, in 43 raiding experiments using colour-marked individuals. In each experiment the colonies of these two ant species, each housed in a plastic box, were placed 12 centimetres apart from each other. © Copyright Reed Business Information Ltd.
Keyword: Chemical Senses (Smell & Taste); Aggression
Link ID: 21526 - Posted: 10.17.2015
What if belief in God and prejudice against immigrants could be altered by magnetic energy? That’s the question researchers sought to explore in a study published Wednesday in the journal Social Cognitive and Affective Neuroscience. The “magnetic energy” comes in the form of transcranial magnetic stimulation (TMS), a noninvasive procedure that uses a metal coil to send pulses to the brain. By activating certain regions of the brain, doctors have used it for things like measuring the damage of a stroke or—increasingly—treating depression. These researchers sought to do the opposite—to temporarily disable one part of the brain (the part that responds to threats) and measure its effect on beliefs and prejudices connected to them. To do this, researchers from Britain’s University of York teamed up with UCLA to find 39 politically moderate college undergraduates who were divided into two groups. The first was given a “love-level sham” dose of TMS that had no effect on their brains. The second got a hit of magnetic energy strong enough to temporarily shut down their posterior medial frontal cortex. The pMFC, as this area near the forehead is known, is the part of the brain that identifies problems and—after measuring the level of threat—generates a response to them. Testing the effect of shutting down the part of the brain that forms judgments based on threats required first presenting threats. After receiving their respective doses of TMS, participants were asked to respond to questions about their own death. Previous studies have shown the threat of death is capable of directly affecting a person’s belief in religion. Therefore, shutting down the part of the brain that registers this threat—they theorized—would reduce the need to believe in God.
Keyword: Emotions
Link ID: 21525 - Posted: 10.17.2015
Three teams of scientists supported by the National Institutes of Health showed that a genetic mutation linked to some forms of amyotrophic lateral sclerosis (ALS) and frontotemporal degeneration (FTD) may destroy neurons by disrupting the movement of materials in and out of the cell’s nucleus, or command center where most of its DNA is stored. The results, published in the journals Nature and NatureNeuroscience, provide a possible strategy for treating the two diseases. “This research shines a spotlight on the role of nuclear transport in the health of neurons,” said Amelie Gubitz, Ph.D., program director at the NIH’s National Institute of Neurological Disorders and Stroke (NINDS). “The results provide new insights into how this mutation derails an essential process in neurons and opens new avenues for therapy development.” Both ALS and FTD are caused by the death of specific neurons. In ALS, this leads to movement difficulties and eventually paralysis, while in FTD, patients experience problems with language and decision making. Past research has connected a specific mutation in the C9orf72 gene to 40 percent of inherited ALS cases and 25 percent of inherited FTD cases, as well as nearly 10 percent of non-inherited cases of each disorder. The recent experiments, conducted in yeast, fruit flies, and neurons from patients, found that the mutation prevents proteins and genetic material called RNA from moving between the nucleus and the cytoplasm that surrounds it. “At the end of the day, this culminates in a defect in the flow of genetic information, which leads to problems expressing genes in the right place at the right time,” said J. Paul Taylor, M.D., Ph.D., a researcher at St. Jude’s Children’s Research Hospital in Memphis, Tennessee, and the senior author of one of the papers.
Keyword: ALS-Lou Gehrig's Disease
Link ID: 21524 - Posted: 10.17.2015
By Anahad O'Connor For years, public health authorities have warned that smartphones, television screens and the hectic pace of modern life are disrupting natural sleep patterns, fueling an epidemic of sleep deprivation. By some estimates, Americans sleep two to three hours fewer today than they did before the industrial revolution. But now a new study is challenging that notion. It found that Americans on average sleep as much as people in three different hunter-gatherer societies where there is no electricity and the lifestyles have remained largely the same for thousands of years. If anything, the hunter-gatherer communities included in the new study — the Hadza and San tribes in Africa, and the Tsimané people in South America — tend to sleep even less than many Americans. The findings are striking because health authorities have long suggested that poor sleep is rampant in America, and that getting a minimum of seven hours on a consistent basis is a necessity for good health. Many studies suggest that lack of sleep, independent of other factors like physical activity, is associated with obesity and chronic disease. Yet the hunter-gatherers included in the new study, which was published in Current Biology, were relatively fit and healthy despite regularly sleeping amounts that are near the low end of those in industrialized societies. Previous research shows that their daily energy expenditure is about the same as most Americans, suggesting physical activity is not the reason for their relative good health. The prevailing notion in sleep medicine is that humans evolved to go to bed when the sun goes down, and that by and large we stay up much later than we should because we are flooded with artificial light, said Jerome Siegel, the lead author of the new study and a professor of psychiatry at the Semel Institute of Neuroscience and Human Behavior at U.C.L.A. © 2015 The New York Times Company
Keyword: Sleep
Link ID: 21523 - Posted: 10.17.2015
by Ben Cipollini Thanks to Ms. Amazing, it’s now cliche to say, but hey… I really love SfN. For the uninitiated SfN is a thirty thousand person international conference for neuroscience–a conference so large, only a few cities in the US can handle it. Yes, that’s a giant C-SPAN2 bus that's dwarfed by this small section of the “Great Room”. For many, SfN evokes fear and dread; it’s truly overwhelming in its size, breadth, and depth. For me, it was love at first “OM*G!!!”. Don’t believe me, scientists? Let’s review the data: I loathe running, but I actually do it at SfN. One needs wheels to get from talks to posters to talks again. We filled the New Orleans convention center in 2012; it’s so long you you can actually get directions from one end of it to the other on Google Maps. Yes, that map does say “1.0 kilometers”. I hate crowds, but I will fight through the poster session crowds like a salmon heading upstream to spawn, just to get to one more poster before the end of the session. SfN may have more human traffic jams than China has vehicle jams during Golden week… but that won’t stop me from finding out how callosal connections have properties similar to those of long-range lateral connections, or to understand how hemispherectomy affects functional organization. You’d better too; you never know when one of your research heroes might be presenting the poster, or you’ll find yourself standing in front of a poster that winds up in Science just a few months later.
Keyword: Miscellaneous
Link ID: 21522 - Posted: 10.17.2015
Peter Andrey Smith Nearly a year has passed since Rebecca Knickmeyer first met the participants in her latest study on brain development. Knickmeyer, a neuroscientist at the University of North Carolina School of Medicine in Chapel Hill, expects to see how 30 newborns have grown into crawling, inquisitive one-year-olds, using a battery of behavioural and temperament tests. In one test, a child's mother might disappear from the testing suite and then reappear with a stranger. Another ratchets up the weirdness with some Halloween masks. Then, if all goes well, the kids should nap peacefully as a noisy magnetic resonance imaging machine scans their brains. “We try to be prepared for everything,” Knickmeyer says. “We know exactly what to do if kids make a break for the door.” Knickmeyer is excited to see something else from the children — their faecal microbiota, the array of bacteria, viruses and other microbes that inhabit their guts. Her project (affectionately known as 'the poop study') is part of a small but growing effort by neuroscientists to see whether the microbes that colonize the gut in infancy can alter brain development. The project comes at a crucial juncture. A growing body of data, mostly from animals raised in sterile, germ-free conditions, shows that microbes in the gut influence behaviour and can alter brain physiology and neurochemistry. © 2015 Nature Publishing Group
Keyword: Obesity; Development of the Brain
Link ID: 21521 - Posted: 10.16.2015
Chris Samoray People in the postindustrial world don’t always get a sound night sleep. But they appear to spend a similar amount of time sleeping as do people in hunter-gatherer communities in Africa and South America, a new study finds. “It’s absolutely clear that they don’t sleep more than we do,” says Jerome Siegel, a UCLA sleep scientist. In fact, on average, hunter-gatherers may sleep a little less. Recommended nightly sleep for adults is typically seven to nine hours; a 2013 Gallup poll showed that most Americans get around 6.8 hours. On most nights, members of three hunter-gatherer groups — the Hadza of Tanzania, the Ju/’hoansi San of Namibia and the Tsimane of Bolivia — sleep 5.7 to 7.1 hours, Siegel and colleagues report online October 15 in Current Biology. That’s on the lower end of the sleep spectrum in postindustrial societies, the researchers say. Evidence from the new study also suggests that these groups experience less insomnia than sleepers in postindustrial societies. (The three hunter-gatherer languages even lack a word for insomnia.) Hunter-gatherer sleep patterns are closely tied to temperature, a new study shows. Among the Hadza of Tanzania, for instance, people fell asleep about three hours after sunset, on average, as ambient temperatures decreased. People then woke up about an hour before sunrise, when temperatures reached their lowest point. © Society for Science & the Public 2000 - 2015.
Keyword: Sleep
Link ID: 21520 - Posted: 10.16.2015
By Robert F. Service Prosthetic limbs may work wonders for restoring lost function in some amputees, but one thing they can’t do is restore an accurate sense of touch. Now, researchers report that one day in the not too distant future, those artificial arms and legs may have a sense of touch closely resembling the real thing. Using a two-ply of flexible, thin plastic, scientists have created novel electronic sensors that send signals to the brain tissue of mice that closely mimic the nerve messages of touch sensors in human skin. Multiple research teams have long worked on restoring touch to people with prosthetic limbs. 2 years ago, for example, a group at Case Western Reserve University in Cleveland, Ohio, reported giving people with prosthetic hands a sense of touch by wiring pressure sensors on the hands to peripheral nerves in their arms. Yet although these advances have restored a rudimentary sense of touch, the sensors and signals are very different from those sent by mechanoreceptors, natural touch sensors in the skin. For starters, natural mechanoreceptors put out what amounts to a digital signal. When they sense pressure, they fire a stream of nerve impulses; the more pressure, the higher the frequency of pulses. But previous tactile sensors have been analogue devices, where more pressure produces a stronger electrical signal, rather than a more frequent stream of pulses. The electrical signals must then be sent to another processing chip that converts the strength of the signals to a digital stream of pulses that is only then sent on to peripheral nerves or brain tissue. © 2015 American Association for the Advancement of Science.
Keyword: Pain & Touch; Robotics
Link ID: 21519 - Posted: 10.16.2015
Could brain inflammation be to blame for schizophrenia? People with the disorder seem to have more active immune cells inside their brains, and now this activity has been spotted even before the disorder develops. This link could be a breakthrough in developing new treatments that better target the causes of the disorder. The idea that the immune system might play a part in schizophrenia was first floated 10 years ago. Since then, a couple of studies have found that people with schizophrenia seem to have more active microglia – the immune cells of the brain. Peter Bloomfield at Imperial College London wondered if this increased immune system activity might be detectable before a person is diagnosed with schizophrenia. His team examined 14 people who had been identified as being at “ultra-high risk” of developing the disorder – they had already seen a doctor about symptoms like paranoia or hallucinations, but hadn’t yet had a psychotic episode. Typically, between 20 and 35 per cent of such individuals will go on to be diagnosed with schizophrenia. By injecting a dye that labels active cells and using a PET scanner, Bloomfield’s team compared the activity of these people’s microglial cells with those of people with schizophrenia, as well as healthy people. They found increased microglial activity in both those who had schizophrenia, and those who had been classified as ultra-high risk. “What’s interesting is that the level of activity correlated with the severity of symptoms,” says Bloomfield. During the study, two of the 14 at ultra-high risk went on to develop schizophrenia and schizotypal disorder – these people had the highest levels of microglial activity, says Bloomfield. © Copyright Reed Business Information Ltd.
Keyword: Schizophrenia; Neuroimmunology
Link ID: 21518 - Posted: 10.16.2015
By Christopher Intagliata
"Babies come prepared to learn any of the world's languages." Alison Bruderer, a cognitive scientist at the University of British Columbia. "Which means no matter where they're growing up in the world, their brains are prepared to pick up the language they're listening to around them."
And listen they do. But another key factor to discerning a language’s particular sounds may be for babies to move their tongues as they listen. Bruderer and her colleagues tested that notion by sitting 24 sixth-month-olds in front of a video screen and displaying a checkerboard pattern, while they played one of two tracks: a single, repeated "D" sound in Hindi, <
Keyword: Language; Development of the Brain
Link ID: 21517 - Posted: 10.16.2015
Using a sensitive new technology called single-cell RNA-seq on cells from mice, scientists have created the first high-resolution gene expression map of the newborn mouse inner ear. The findings provide new insight into how epithelial cells in the inner ear develop and differentiate into specialized cells that serve critical functions for hearing and maintaining balance. Understanding how these important cells form may provide a foundation for the potential development of cell-based therapies for treating hearing loss and balance disorders. The research was conducted by scientists at the National Institute on Deafness and Other Communication Disorders (NIDCD), part of the National Institutes of Health. In a companion study led by NIDCD-supported scientists at the University of Maryland School of Medicine and scientists at the Sackler School of Medicine at Tel Aviv University, researchers used a similar technique to identify a family of proteins critical for the development of inner ear cells. Both studies were published online on October 15 in the journal Nature Communications. “Age-related hearing loss occurs gradually in most of us as we grow older. It is one of the most common conditions among older adults, affecting half of people over age 75,” said James F. Battey, Jr., M.D., Ph.D., director of the NIDCD. “These new findings may lead to new regenerative treatments for this critical public health issue.” Specialized sensory epithelial cells in the inner ear include hair cells and supporting cells, which provide the hair cells with crucial structural and functional support. Hair cells and supporting cells located in the cochlea — the snail-shaped structure in the inner ear — work together to detect sound, thus enabling us to hear. In contrast, hair cells and supporting cells in the utricle, a fluid-filled pouch near the cochlea, play a critical role in helping us maintain our balance.
Keyword: Hearing; Genes & Behavior
Link ID: 21516 - Posted: 10.16.2015
by Helen Thompson It's no secret that some plants lace their nectar with caffeine in an effort to attract more pollinators, and that buzz sticks around in a bee's memory. These caffeinated flowers lure naive honeybees to return over and over again — and bring their friends, researchers report October 15 in Current Biology. When feeding off caffeinated nectar (versus noncaffeinated nectar), honeybees increased their foraging activity and performed four times as many waggle dances to alert other workers to food sources. Though bees might be more persistent foragers while under the influence of caffeine, they focused mainly on caffeinated sources instead casting a broad search. Plants may also substitute caffeine for sugar, the researchers note, duping bees into gathering nectar that's less valuable for honey production. © Society for Science & the Public 2000 - 2015.
Keyword: Drug Abuse; Evolution
Link ID: 21515 - Posted: 10.16.2015
Kerri Smith Scientists have discovered two extra neurons in a worm species that — they thought — already had its entire nervous system mapped. “It is a bit of a shock,” says Richard Poole, a developmental biologist at University College London (UCL), and one of the team that found the neurons by accident. The researchers call them mystery cells of the male, or MCMs, because they are found only in male nematode worms. The neurons help the worms learn when to prioritize mating over eating, revealing how a seemingly simple brain can be capable of a complex learned behaviour — and one that differs between the sexes. Caenorhabditis elegans worms are the model animal of choice for many neuroscientists, because their neural circuits are so simple that they can be mapped in full. They have two sexes: hermaphrodite and male. Hermaphrodites, the best studied, have just 302 neurons, but males have more — the MCMs raise their total to 385 neurons1. The two ‘mystery’ cells were discovered when Poole’s colleague at UCL, Arantza Barrios, was looking at the distribution of a peptide often found in neurons, called pdf-1. She saw cells light up where she thought they should not — near the worm’s nose. The neurons develop when male worms reach maturity, the researchers worked out. Their report is published in Nature1. Sex or food? © 2015 Nature Publishing Group,
Keyword: Sexual Behavior; Development of the Brain
Link ID: 21514 - Posted: 10.15.2015
By Nicholas Bakalar Physical therapy may provide little relief for recent-onset low back pain, a small randomized trial has found. The study, published in JAMA, included 207 men and women, average age 37, with a score of 20 or higher on a widely used 100-point scale that quantifies disability from low back pain. The study included people with recent-onset pain who were assigned to one of two groups. The first received four sessions of exercise and manipulation under the guidance of a trained physical therapist. Those in the other group were told that low back pain usually gets better, and were advised to be as active as possible. There were no significant differences at any time in pain intensity, quality of life or the number of visits to health care providers. Compared with the usual care group, the physical therapy group did show significant improvement on the disability scale after three months. But after one year, there was no difference between the two groups in this measure either. “Most treatments that are effective have only modest effects,” said the lead author, Julie M. Fritz, a professor in the department of physical therapy at the University of Utah. “The pattern of low back pain is one of recurrence and remission, and changing that pattern is a real challenge. There are no magic answers.” © 2015 The New York Times Company
Keyword: Pain & Touch
Link ID: 21513 - Posted: 10.15.2015
By AUSTIN RAMZY HONG KONG — Australian officials have responded to criticism from animal rights activists and celebrities, including the former actress Brigitte Bardot and the singer Morrissey, that a government plan to protect threatened species by killing millions of feral cats is unnecessarily cruel. Gregory Andrews, Australia’s threatened species commissioner, has written open letters to Ms. Bardot and Morrissey saying that feral cats prey on more than 100 of the country’s threatened species and that they were a “major contributor” to the extinction of at least 27 mammal species in the country over the past 200 years. He called some of the extinct species, such as the lesser bilby, desert bandicoot, crescent nailtail wallaby and big-eared hopping mouse, “delightful creatures, rich in importance in Australian indigenous culture, and formerly playing important roles in the ecology of our country. We don’t want to lose any more species like these.” The Australian Department of the Environment says that feral cats are the biggest threat to the country’s mammals, ahead of foxes and habitat loss. The government plan would use poison and traps to kill the cats. In announcing the plan in July, Greg Hunt, the environment minister, said that he wanted two million feral cats culled by 2020. Australia has an estimated 20 million feral cats, which are an invasive species brought by European settlers. Calls to exterminate the cats have been floated before, including one in the 1990s that called for killing all feral cats by 2020. © 2015 The New York Times Company
Keyword: Animal Rights
Link ID: 21512 - Posted: 10.15.2015
by Bethany Brookshire It’s happened to all of us at one time or another: You’re walking through a crowd, and suddenly a face seems incredibly familiar — so much so that you do a double-take. Who is that? How do you know them? You have no idea, but something about their face nags at you. You know you’ve seen it before. The reason you know that face is in part because of your perirhinal cortex. This is an area of the brain that helps us to determine familiarity, or whether we have seen an object before. A new study of brain cells in this area finds that firing these neurons at one frequency makes the brain treat novel images as old hat. But firing these same neurons at another frequency can make the old new again. “Novelty and familiarity are both really important,” says study coauthor Rebecca Burwell, a neuroscientist at Brown University in Providence, R.I. “They are important for learning and memory and decision making.” Finding a cache of food and knowing it is new could be useful for an animal’s future. So is recognizing a familiar place where the pickings were good in the past. But knowing that something is familiar is not quite the same thing as knowing what that thing is. “You’re in a crowd and you see a familiar face, and there’s a feeling,” Burwell explains. “You can’t identify them, you don’t know where you met them, but there’s a sense of familiarity.” It’s different from recalling where you met the person, or even who the person is. This is a sense at the base of memory. And while scientists knew the perirhinal cortex was involved in this sense of familiarity, how that feeling of new or old was coded in the brain wasn’t fully understood. © Society for Science & the Public 2000 - 2015
Keyword: Attention
Link ID: 21511 - Posted: 10.14.2015
Gene therapy preserved vision in a study involving dogs with naturally occurring, late-stage retinitis pigmentosa, according to research funded by the National Eye Institute (NEI), part of the National Institutes of Health. The findings contribute to the groundwork needed to move gene therapy forward into clinical trials for people with the blinding eye disorder, for which there is currently no cure. Scientists from the University of Pennsylvania and the University of Florida, Gainesville also determined for the first time that gene therapy may be of potential benefit even after there has been significant loss of cells in the eye. Up to this point, animal studies had shown benefits from gene therapy only when it was used in the earliest stages of the disease. “The study shows that a corrective gene can stop the loss of photoreceptors in the retina, and provides good proof of concept for gene therapy at the intermediate stage of the disease, thus widening the therapeutic window,” said Neeraj Agarwal, Ph.D., a program director at NEI. Retinitis pigmentosa is the most common inherited disease that causes degeneration of the retina, the light-sensitive tissue lining the back of the eye. Roughly 1 in 4,000 people are affected and about 10 to 20 percent have a particularly severe form called X-linked retinitis pigmentosa, which predominately affects males, causing night blindness by age 10 and progressive loss of the visual field by age 45. About 70 percent of people with the X-linked form carry mutations that cause loss of function of the retinitis pigmentosa GTPase Regulator (RPGR) gene, which encodes a protein important for maintaining the health of photoreceptors.
Keyword: Vision
Link ID: 21510 - Posted: 10.14.2015
By Gretchen Reynolds Can a shot of salt water make you a faster runner? The answer appears to be a resounding yes, if you believe that the salt water contains something that should make you a faster runner, according to a new study of the power of placebos in athletic performance. Anyone who exercises knows from experience that our minds and mental attitudes affect physical performance. Who hasn’t faced a moment when, tiring at the end of a strenuous workout or race, we are about to quit before suddenly being passed on the path or shown up in the gym by someone we know we should outperform, and somehow we find an extra, unexploited gear and spurt on? This phenomenon is familiar to physiologists, many of whom believe that our brains, in order to protect our bodies, send out signals telling those bodies to quit before every single resource in our muscles and other tissues is exhausted. We think we are at the outer limits of our endurance or strength, when, in reality, we may still have a physical reserve available to us, if we can find a way to tap it. Past studies have shown that lying to people is one way to exploit that reserve. Telling athletes that they are moving slower than in fact they are, for instance, often results in their speeding up past the pace that they thought they could maintain. Or give them a sugar pill that they think contains caffeine or steroids and they will run more swiftly or lift more weight than before. But none of these studies tested the effects of placebos and deception in relatively real-world competitive situations, which have their own effects on mental responses. People are almost always faster during competitive races than in training, studies show, even when they are trying to replicate race pace. © 2015 The New York Times Company
Keyword: Pain & Touch
Link ID: 21509 - Posted: 10.14.2015
By Christopher Intagliata If you're lost, you need a map and a compass. The map pinpoints where you are, and the compass orients you in the right direction. Migratory birds, on the other hand, can traverse entire hemispheres and end up just a couple miles from where they bred last year, using their senses alone. Their compass is the Sun, the stars and the Earth's magnetic field. But their map is a little more mysterious. One theory goes that they use olfactory cues—how a place smells. Another is that they rely on their sense of magnetism. Researchers in Russia investigated the map issue in a past study by capturing Eurasian reed warblers on the Baltic Sea as they flew northeast towards their breeding grounds near Saint Petersburg. They moved the birds 600 miles east, near Moscow. And the birds just reoriented themselves to the northwest—correctly determining their new position. Now the same scientists have repeated that experiment—only this time, they didn't move the birds at all. They just put them in cages that simulated the magnetic field of Moscow, while still allowing the birds to experience the sun, stars and smells of the Baltic. Once again, the birds re-oriented themselves to the northwest—suggesting that the magnetic field alone—regardless of smells or other cues, is enough to alter the birds' mental map. The study is in the journal Current Biology. [Dmitry Kishkinev et al, Eurasian reed warblers compensate for virtual magnetic displacement] And if you're envious of that sixth sense—keep in mind that since the Earth's magnetic field fluctuates, the researchers say magnetic route-finding is best for crude navigation. Meaning for door-to-door directions—you’re still better off with your GPS. © 2015 Scientific American,
Keyword: Animal Migration
Link ID: 21508 - Posted: 10.14.2015


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