Chapter 16. None

Follow us on Facebook and Twitter, or subscribe to our mailing list, to receive news updates. Learn more.


Links 21 - 40 of 2150

By Karen Weintraub Can I ever re-pay my sleep debt? (I estimate it at 15 years of poor sleep.) It is unclear whether you can make up a long-term sleep debt, because most studies have looked at the effects of sleep loss and recovery only over a few nights or weeks, said Dr. Matt T. Bianchi, the chief of the division of sleep medicine at Massachusetts General Hospital and an assistant professor of neurology at Harvard Medical School. Simulated driving performance and reaction times are affected by just one sleepless night, research has shown. There’s no doubt that sleeping just four hours a night catches up to people within a few nights, leading to impairments of attention, learning and memory and worse performance in school and at work. And making up for lost sleep over the weekend doesn’t work. Five brief nights quickly add up to a shortfall of 20 hours, but people don’t sleep more than five to 10 extra hours to compensate, Dr. Bianchi said. “The interpretation has been you can’t pay off your sleep debt, you just carry it with you,” though it’s also possible that people don’t sleep an extra 20 hours because they don’t need it, Dr. Bianchi said. He cited research by Jim Horne of Loughborough University in Britain showing that a timely nap of less than 20 minutes can equate to an extra hour of nighttime sleep. Different people need somewhat different amounts of sleep, but anything less than six hours a night is definitely not enough, said Dr. Charles Czeisler, a professor of sleep medicine at Harvard. In one sleep study, people were brought into a lab and required to stay in bed for 14 hours a day. They slept 10 to 12 hours a night at first, Dr. Czeisler said. Then they gradually slept less over the next few weeks until they stabilized at about 8.4 hours per night. © 2015 The New York Times Company

Keyword: Sleep
Link ID: 21223 - Posted: 07.27.2015

By Claire Asher City folk have a reputation for being less friendly than their rural counterparts, and the same appears to be true for garden birds. Urban song sparrows (Melospiza melodia, pictured) are more aggressive toward their neighbors than are sparrows out in the country, researchers report this month in Behavioral Ecology. But whereras the temperament of human city-dwellers is often attributed to the sheer density of people, this isn’t the case for sparrows. The team measured birds’ responses to recordings of another male’s song, noting how often males approached or attacked the speakers, and found that aggression depended not on the density of sparrows, but on the availability of food in the environment. Counterintuitively, male sparrows responded more aggressively in the city, where there tends to be more food, and rural birds became more aggressive when provided with food supplements. The authors explain that the sparrows defend food-rich, high-quality territories more aggressively, but it isn’t clear whether this is an offensive or a defensive strategy; city birds may be more aggressive because a territory with more food is more valuable to them, or because their abundant resources attract more thieves. © 2015 American Association for the Advancement of Science.

Keyword: Aggression
Link ID: 21221 - Posted: 07.27.2015

Alison Abbott Neuroscientists have identified an area of the brain that might give the human mind its unique abilities, including language. The area lit up in human, but not monkey, brains when they were presented with different types of abstract information. The idea that integrating abstract information drives many of the human brain's unique abilities has been around for decades. But a paper published1 in Current Biology, which directly compares activity in human and macaque monkey brains as they listen to simple auditory patterns, provides the first physical evidence that a specific area for such integration may exist in humans. Other studies that compare monkeys and humans have revealed differences in the brain’s anatomy, for example, but not differences that could explain where humans’ abstract abilities come from, say neuroscientists. “This gives us a powerful clue about what is special about our minds,” says psychologist Gary Marcus at New York University. “Nothing is more important than understanding how we got to be how we are.” A team of researchers headed by Stanislas Dehaene at the INSERM Cognitive Neuroimaging Unit at Gif-sur-Yvette near Paris, looked at changing patterns of activation in the brain as untrained monkeys and human adults listened to a simple sequence of tones, for example three identical tones followed by a different tone (like the famous four-note opening of Beethoven’s fifth symphony: da-da-da-DAH). The researchers played several different sequences with this structure — known as AAAB — and other sequences to the subjects while they lay in a functional magnetic resonance imaging (fMRI) scanner. The fMRI technique picks up changes in blood flow in the brain that correlate with regional brain activity. © 2015 Nature Publishing Group,

Keyword: Attention; Evolution
Link ID: 21220 - Posted: 07.25.2015

A panel of independent experts has decided that a clot-busting drug often used to treat strokes is "safe and effective". The UK medicines watchdog wanted the benefits and risks of alteplase to be analysed after concerns were raised about its safety. The panel concluded that the best time to use the drug is up to four and a half hours after the start of symptoms. But some other doctors are still not convinced by the evidence. Most strokes are caused by a clot blocking the flow of blood to the brain. Many patients are given the drug alteplase to break down and disperse the clot - a treatment known as thrombolysis. The independent expert panel, chaired by Prof Sir Ian Weller, said it had looked at all available data on alteplase and decided that the earlier the drug was given to patients, the greater the chance of a good outcome. Used up to four and a half hours after the onset of symptoms, the benefits of the drug were found to outweigh the risks. But it added that the benefits of using alteplase to treat strokes were "highly time-dependent" and, in a small number of people, there was a risk of haemorrhage. Prof Weller explained: "The evidence shows that for every 100 patients treated with alteplase, whilst there is an early risk of a fatal bleed in two patients, after three to six months, around 10 more in every 100 are disability-free when treated within three hours." © 2015 BBC.

Keyword: Stroke
Link ID: 21218 - Posted: 07.25.2015

By Karen Weintraub Can I ever re-pay my sleep debt? (I estimate it at 15 years of poor sleep.) It is unclear whether you can make up a long-term sleep debt, because most studies have looked at the effects of sleep loss and recovery only over a few nights or weeks, said Dr. Matt T. Bianchi, the chief of the division of sleep medicine at Massachusetts General Hospital and an assistant professor of neurology at Harvard Medical School. Simulated driving performance and reaction times are affected by just one sleepless night, research has shown. There’s no doubt that sleeping just four hours a night catches up to people within a few nights, leading to impairments of attention, learning and memory and worse performance in school and at work. And making up for lost sleep over the weekend doesn’t work. Five brief nights quickly add up to a shortfall of 20 hours, but people don’t sleep more than five to 10 extra hours to compensate, Dr. Bianchi said. “The interpretation has been you can’t pay off your sleep debt, you just carry it with you,” though it’s also possible that people don’t sleep an extra 20 hours because they don’t need it, Dr. Bianchi said. He cited research by Jim Horne of Loughborough University in Britain showing that a timely nap of less than 20 minutes can equate to an extra hour of nighttime sleep. Different people need somewhat different amounts of sleep, but anything less than six hours a night is definitely not enough, said Dr. Charles Czeisler, a professor of sleep medicine at Harvard. © 2015 The New York Times Company

Keyword: Sleep
Link ID: 21214 - Posted: 07.25.2015

By Annick Laurent Can you tell a pygmy blue whale from an Antarctic blue whale? If not, you aren’t alone. Marine biologists have had trouble distinguishing these enormous mammals with mottled skin patterns ever since they began studying them—and that has complicated efforts to figure out where they breed and how to best protect them. Now, researchers have caught a break thanks to a pygmy whale named Isabela. Researchers first photographed the whale and collected her DNA in 1998 in the waters off the Galapagos Islands. Then, in 2006, another team photographed and collected samples from a similar looking whale off Chile (both photos above). Now, in a study published online before print in Marine Mammal Science, scientists compared those samples and photographs, and discovered that they both belonged to the same whale. That means Isabela (named after the lead author’s daughter to represent hope for future preservation efforts) migrated a minimum of 5200 km, the longest recorded latitudinal migration made by any Southern Hemisphere blue whale on record. The findings suggest Chile's and the Galapagos’ blue whale aggregations are connected, meaning those feeding in the Gulf of Corcovado off Chile may be breeding in the Tropical Eastern Pacific. Knowing where this species migrates—including its feeding and breeding grounds—can help conservationists and governments better establish marine protected areas, the team says. © 2015 American Association for the Advancement of Science

Keyword: Animal Migration
Link ID: 21213 - Posted: 07.25.2015

Jon Hamilton The face of Alzheimer's isn't always old. Sometimes it belongs to someone like Giedre Cohen, who is 37, yet struggles to remember her own name. Until about a year ago, Giedre was a "young, healthy, beautiful" woman just starting her life, says her husband, Tal Cohen, a real estate developer in Los Angeles. Now, he says, "her mind is slowly wasting away." People like Giedre have a rare gene mutation that causes symptoms of Alzheimer's to appear before they turn 60. Until recently, people who inherited this gene had no hope of avoiding dementia and an early death. Now there is a glimmer of hope, thanks to a project called DIAN TU that is allowing them to take part in a study of experimental Alzheimer's drugs. The project also could have a huge payoff for society, says Dr. Randall Bateman, a professor of neurology at Washington University in St. Louis. "It's highly likely," he says, that the first drug able to prevent or delay Alzheimer's will emerge from studies of people genetically destined to get the disease. Giedre Cohen enrolled in the DIAN TU study in 2013, when she still had no symptoms of Alzheimer's, her husband says. Their story began more than a decade earlier. In 2002, Tal Cohen was on a trip to Miami to attend a wedding. He met Giedre, who was born in Lithuania, and the two fell in love. © 2015 NPR

Keyword: Alzheimers
Link ID: 21211 - Posted: 07.23.2015

THERE’S more to semen than sperm. In many animals, seminal fluid alters both the bodies and sometimes even the behaviour of females. Human semen, too, triggers changes in the uterus, and might have wider effects on women, aimed at just one goal. “It’s all about maximising the chances of the male reproducing,” says Sarah Robertson of the University of Adelaide in Australia. The effects are most striking in fruit flies: seminal fluid can make the females eat more, lay more eggs and be less receptive to other males. Now a team led by Tracey Chapman at the University of East Anglia in Norwich, UK, has found that male fruit flies selectively alter the chemical make-up of their seminal fluid. In the presence of rivals, the males produce more seminal proteins. “It came as a real surprise,” says Chapman. “It’s a sophisticated response to the social and sexual situation.” Some of their findings were presented at the Society for Molecular Biology and Evolution conference in Vienna, Austria, last week, including their discovery that one of these proteins is a “master regulator” of genes. Females exposed to it show a wide range of changes in gene expression. Chapman thinks this kind of seminal signalling is widespread in the animal world. The semen of people, pigs and mice affects the female reproductive tract, and the question is whether it can also produce behavioural responses in female mammals similar to those seen in fruit flies. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Evolution
Link ID: 21209 - Posted: 07.23.2015

Jessie Rack If you've ever had hiccups in a quiet room, you know how embarrassing and completely uncontrollable they can feel. What if, instead of the hiccups, your body jerked involuntarily or you blurted out words without meaning to? That's a rough idea of what living with Tourette syndrome can be like. Designers of a new computer program called TicHelper hope that they will be able to help children recognize and control these impulses themselves. People with Tourette's perform repetitive movements or vocalizations called tics. A simple tic might be something like head jerking, eye blinking, or throat clearing, and a complex tic might involve patterns of movement or saying multiple words or phrases. We don't know exactly what causes Tourette's, says Douglas Woods, a psychologist at Texas A&M University. Woods, who is also co-chair of the Tourette Association of America Medical Advisory Board, is one of the minds behind TicHelper. "Sometimes kids will grow out of [Tourette's]," Woods says. But if the wait-and-see approach isn't working, and the tics are interfering with daily life, there are a few treatment options. One option is medication. Woods says there are a few different antipsychotic drugs that are used to manage Tourette syndrome, but they have side effects and don't always work. An alternative to pharmaceutical treatment is behavioral therapy. A form of behavioral therapy called comprehensive behavioral intervention for tics, or CBIT for short, is commonly used. CBIT training teaches people with Tourette's to recognize the onset of a tic and to perform a different behavior when they feel one coming on. © 2015 NPR

Keyword: Tourettes
Link ID: 21208 - Posted: 07.23.2015

By Warren Cornwall The number of U.S. school children placed in special education programs due to autism more than tripled from 2000 to 2010, to nearly 420,000. But a new study argues much of that increase likely came as educators swapped one diagnosis for another. The overall percentage of kids diagnosed with a collection of brain development problems that includes autism remained unchanged, suggesting that children who used to be labeled with conditions such as “intellectual disability” were in fact autistic. “If you asked me, ‘Is there a real increase in the prevalence of autism?’ maybe there is, but probably much lower than the reported magnitude,” says Santhosh Girirajan, a geneticist at Pennsylvania State University (Penn State), University Park. In the new study, Girirajan and colleagues combed through data collected in each state for approximately 6.2 million U.S. school children with disabilities who are enrolled in special education programs. The information is collected each year under the federal Individuals with Disabilities Education Act. Based on his or her diagnosis, each child was assigned to one of 13 broader categories, ranging from autism to physical challenges such as blindness. Between 2000 and 2010, the number of children in the autism category more than tripled from 93,624 in 2000 to 419,647 a decade later. Yet nearly two-thirds of that increase was matched by a decline in the rate at which children were labeled as having an “intellectual disability.” The number of kids in that category fell from 637,270 to 457,478. © 2015 American Association for the Advancement of Science.

Keyword: Autism
Link ID: 21207 - Posted: 07.23.2015

By Sandhya Somashekhar NEW WESTMINSTER, B.C. — Alanna Whitney was a weird kid. She had a strange knack for pronouncing long words. Anchovies on pizza could send her cowering under a table. Her ability to geek out on subjects such as Greek mythology and world religions could be unsettling. She drank liquids obsessively, and in her teens, her extreme water intake landed her in the hospital. Years later, she found a word that explained it all: Autistic. Instead of grieving, she felt a rush of relief. “It was the answer to every question I’d ever had,” she recalled. “It was kind of like a go-ahead to shed all of those things I could or couldn’t do and embrace myself for who I am.” So it came to be that Whitney, 24, was arranging strawberries and store-bought cookies on platters at the Queensborough Community Center for a celebration of “Autistic Pride Day,” her shoulder-length hair dyed mermaid green to match her purse and sandals. A bowl of orange earplugs sat nearby in case any of the guests found the ambient sounds overwhelming. Whitney is part of a growing movement of autistic adults who are finding a sense of community, identity and purpose in a diagnosis that most people greet with dread. These “neurodiversity” activists contend that autism — and other brain afflictions such as dyslexia and attention deficit hyperactivity disorder — ought to be treated not as a scourge to be eradicated but rather as a difference to be understood and accepted.

Keyword: Autism
Link ID: 21206 - Posted: 07.23.2015

By Hanae Armitage Cataracts cloud the eyes of tens of millions of people around the world and nearly 17.2% of Americans over the age of 40. Currently, the only treatment is surgery—lasers or scalpels cut away the molecular grout that builds in the eye as cataracts develop, and surgeons sometimes replace the lens. But now, a team of scientists and ophthalmologists has tested a solution in dogs that may be able to dissolve the cataract right out of the eye’s lens. And the solution is itself a solution: a steroid-based eye drop. Though scientists don’t fully understand how cataracts form, they do know that the “fog” often seen by patients is a glob of broken proteins, stuck together in a malfunctioning clump. When healthy, these proteins, called crystallins, help the eye’s lens keep its structure and transparency. But as humans and animals alike get older, these crystallin proteins start to come unglued and lose their ability to function. Then they clump together and form a sheathlike obstruction in the lens, causing the signature “steamy glass” vision that accompanies cataracts. Coming up with a solution other than surgery has been tough. Scientists have been hunting for years for mutations in crystallin proteins that might offer new insights and pave the way to an alternate therapy. Now, it looks like a team led by University of California (UC), San Diego, molecular biologist Ling Zhao may have done just that. Her team came up with the eye drop idea after finding that children with a genetically inherited form of cataracts shared a mutation that stopped the production of lanosterol, an important steroid in the body. When their parents did not have the same mutation, the adults produced lanosterol and had no cataracts. © 2015 American Association for the Advancement of Science.

Keyword: Vision
Link ID: 21205 - Posted: 07.23.2015

By James Gallagher Health editor, BBC News website The first hints a drug can slow the progression of Alzheimer's disease have emerged at a conference. Data from pharmaceutical company Eli Lilly suggests its solanezumab drug can cut the rate of the dementia's progression by about a third. The results are being met with cautious optimism, with a separate trial due to report next year. The death of brain cells in Alzheimer's is currently inexorable. Solanezumab may be able to keep them alive. Current medication, such as Aricept, can only manage the symptoms of dementia by helping the dying brain cells function. But solanezumab attacks the deformed proteins, called amyloid, that build up in the brain during Alzheimer's. It is thought the formation of sticky plaques of amyloid between nerve cells leads to damage and eventually brain cell death. Solanezumab has long been the great hope of dementia research, yet an 18-month trial of the drug seemingly ended in failure in 2012. But when Eli Lilly looked more closely at the data, there were hints it could be working for patients in the earliest stages of the disease. So the company asked just over 1,000 of the patients in the original trial with mild Alzheimer's to take the drug for another two years. And the results from this extension of the original trial have now been presented, at the Alzheimer's Association International Conference. Dr Eric Siemers, from the Lilly Research Laboratories, in Indiana, told the BBC: "It's another piece of evidence that solanezumab does have an effect on the underlying disease pathology. "We think there is a chance that solanezumab will be the first disease-modifying medication to be available." The company also started a completely separate trial in mild patients in 2012, and these results could prove to be the definitive moment for the drug. © 2015 BBC.

Keyword: Alzheimers
Link ID: 21203 - Posted: 07.22.2015

Ewen Callaway A mysterious group of humans crossed the Bering land bridge from Siberia into the Americas thousands of years ago, genetic analyses reveal. Modern-day signatures of this ‘ghost population’ survive in people who live deep in the Brazilian Amazon, but the two research teams who have made the discovery have different ideas about when and how these migrants reached the Americas1, 2. "This is an unexpected finding," says Jennifer Raff, an anthropological geneticist at the University of Texas at Austin who was not involved in either study. "It’s honestly one of the most exciting results we’ve seen in a while." North and South America were the last continents that humans settled. Previous studies of DNA from modern and ancient Native Americans suggest that the trek was made at least 15,000 years ago (although the timing is not clear-cut) by a single group dubbed the ‘First Americans’, who crossed the Bering land bridge linking Asia and North America. “The simplest hypothesis would be that a single population penetrated the ice sheets and gave rise to most of the Americans,” says David Reich, a population geneticist at Harvard Medical School in Boston, Massachusetts. In 2012, his team found evidence for a single founding migration in the genomes from members of 52 Native American groups3. So Reich was flabbergasted when a colleague called Pontus Skoglund mentioned during a conference last year that he had found signs of a second ancient migration to the Americas lurking in the DNA of contemporary Native Amazonians. Reich wasted no time in verifying the discovery. “During the session afterward, he passed his laptop over the crowd, and he had corroborated the results,” says Skoglund, who is now a researcher in Reich’s lab. © 2015 Nature Publishing Group

Keyword: Genes & Behavior
Link ID: 21201 - Posted: 07.22.2015

By Smitha Mundasad Health reporter A type of diabetes drug may offer a glimmer of hope in the fight against Parkinson's disease, research in the journal Plos Medicine suggests. Scientists found people taking glitazone pills were less likely to develop Parkinson's than patients on other diabetes drugs. But they caution the drugs can have serious side-effects and should not be given to healthy people. Instead, they suggest the findings should prompt further research. 'Unintended benefits' There are an estimated 127,000 people in the UK with Parkinson's disease, which can lead to tremor, slow movement and stiff muscles. And charities say with no drugs yet proven to treat the condition, much more work is needed in this area. The latest study focuses solely on people with diabetes who did not have Parkinson's disease at the beginning of the project. Researchers scoured UK electronic health records to compare 44,597 people prescribed glitazone pills with 120,373 people using other anti-diabetic treatment. They matched participants to ensure their age and stage of diabetes treatment were similar. Scientists found fewer people developed Parkinson's in the glitazone group - but the drug did not have a long-lasting benefit. Any potential protection disappeared once patients switched to another type of pill. Dr Ian Douglas, lead researcher at the London School of Hygiene and Tropical Medicine, said: "We often hear about negative side-effects associated with medications, but sometimes there can also be unintended beneficial effects. "Our findings provide unique evidence that we hope will drive further investigation into potential drug treatments for Parkinson's disease." © 2015 BBC

Keyword: Parkinsons
Link ID: 21199 - Posted: 07.22.2015

By BENEDICT CAREY Bill Cosby stands accused of committing date rape long before drugs like GHB or Rohypnol were widely used for that purpose. Many of Mr. Cosby’s accusers believed they had been drugged — but with what? And how? In a recently obtained legal deposition, Mr. Cosby acknowledged giving quaaludes to some women with whom he had sex, but said consumption of the drug was consensual, “the same as a person would say, ‘Have a drink.’ ” In a transcript of the deposition, reported on Sunday in The New York Times, the comedian told lawyers had had obtained seven prescriptions for quaaludes. Originally approved and marketed as a “safer” sleeping pill, less addictive than barbiturates, the drug (known generically as methaqualone) was both sedating and hypnotic. Recreational use was common, but the federal government withdrew them from the market in 1982. “It was inevitable that it would be tried by people looking for a ‘better high,’ ” Dr. David Smith, medical director of the Haight-Ashbury Free Clinic, and Dr. Donald Wesson noted in The Journal of Psychedelic Drugs. Intoxication with quaaludes “soon developed a reputation for being especially pleasant.” Young people in the 1970s used quaaludes as they would a strong drink: to loosen up, to relax, to socialize. The pills also won a reputation for inducing periods of euphoria, as well as sexual arousal — “heroin for lovers,” some called it. By the middle of the decade, quaaludes were a staple of the club scene, often taken with alcohol. So embedded were quaaludes in the cultural scene that even years later the Dead Kennedys and Billy Idol were singing about the drug’s captivating effects. But reckless users risked overdose, especially when combining the pills with alcohol, which could lead to coma, convulsions and sometimes death. In a 1973 review of 252 hospital admissions for drug overdose, doctors in Edinburgh found that the third most common cause of “self-poisoning,” after barbiturates and LSD, was Mandrax — the British version of quaaludes, widely abused in South Africa as well. © 2015 The New York Times Company

Keyword: Drug Abuse
Link ID: 21198 - Posted: 07.22.2015

Carl Zimmer An ant colony is an insect fortress: When enemies invade, soldier ants quickly detect the incursion and rip their foes apart with their oversize mandibles. But some invaders manage to slip in with ease, none more mystifyingly than the ant nest beetle. Adult beetles stride into an ant colony in search of a mate, without being harassed. They lay eggs, from which larva hatch. As far as scientists can tell, workers feed the young beetles as if they were ants. When the beetles grow into adults, the ants swarm around them, grooming their bodies. In exchange for this hospitality, the beetles sink their jaws into ant larvae and freshly moulted adults in order to drink their body fluids. “They’re like vampire beetles wandering in the ant nests,” said Andrea Di Giulio, an entomologist at Roma Tre University in Rome. Dr. Di Giulio and his colleagues have now uncovered a remarkable trick that the beetles use to fool their hosts. It turns out they can perform uncanny impressions, mimicking a range of ant calls. Dr. Di Giulio and his colleagues study a species of ant nest beetle called Paussus favieri, which lives in the Atlas Mountains of Morocco, where it infiltrates the nests of Moroccan ants, known as Pheidole pallidula. Like many ant species, Pheidole pallidula makes noises by rubbing its legs against ridges on its body. The meanings of these signals vary from species to species; leaf-cutting ants summon bodyguards for the march back to the nest; in other species, a queen trills to her workers to attend to her. Scientists have found that Pheidole pallidula ants make three distinct sounds, each produced by a different caste: soldiers, workers and the queen. © 2015 The New York Times Company

Keyword: Evolution; Language
Link ID: 21193 - Posted: 07.20.2015

by Stephen Buchmann Flowers, bugs and bees: Stephen Buchmann wanted to study them all when he was a kid. "I never grew out of my bug-and-dinosaur phase," he tells NPR's Arun Rath. "You know, since about the third grade, I decided I wanted to chase insects, especially bees." These days, he's living that dream. As a pollination ecologist, he's now taking a particular interest in how flowers attract insects. In his new book, The Reason for Flowers, he looks at more than just the biology of flowers — he dives into the ways they've laid down roots in human history and culture, too. On the real 'reason for flowers' The reason for flowers is actually one word: sex. So, flowers are literally living scented billboards that are advertising for sexual favors, whether those are from bees, flies, beetles, butterflies or us, because quite frankly most of the flowers in the world have gotten us to do their bidding. But that's only the first stage because flowers, if they're lucky, turn into fruits, and those fruits and seeds feed the world. On the raucous secret lives of beetles One of my favorite memories is roaming the Napa foothills as a UC Davis grad student. And I would go to the wineries, of course, and in between I would find western spice bush, which is this marvelous flower that kind of smells like a blend between a cabernet and rotten fruit. And when you find those flowers and open them up, you discover literally dozens of beetles in there, mating, defecating, pollinating — having a grand time. © 2015 NPR

Keyword: Sexual Behavior; Evolution
Link ID: 21192 - Posted: 07.20.2015

By NANCY L. SEGAL, AARON T. GOETZ and ALBERTO C. MALDONADO SEVERAL years ago, while browsing the campus bookstore, one of us, Professor Segal, encountered a display table filled with Squirtles. A Squirtle is a plush-toy turtle manufactured by the company Russ Berrie. They were adorable and she couldn’t wait to take one home. Afterward, Professor Segal began wondering why this toy was so attractive and suspected that its large, round eyes played a major role. It’s well known that a preference for large eyes emerges in humans by 5 months of age. But the Squirtle was even more appealing than many of its big-eyed competitors. Was there something else about its eyes? Professor Segal consulted one of us, Professor Goetz, a colleague in evolutionary psychology, who suggested that because the Squirtle’s eyes were bordered in white, the cooperative eye hypothesis might have answers. This hypothesis, developed by the Japanese researchers Hiromi Kobayashi and Shiro Kohshima, holds that the opaque white outer coating of the human eye, or sclera, evolved to assist communication between people by signaling the direction of their gaze. The clear visibility of the sclera is a uniquely human characteristic. Other primates, such as the African great apes, also track the gaze direction of others, yet their sclera are pigmented or, if white, not visible. The great apes appear to use head direction more than other cues when following another’s gaze. Do humans have an instinctive preference for the whites of eyes, thus explaining the allure of the Squirtle? We conducted a study, to be published this year in the journal Evolution and Human Behavior, that suggested that the answer was yes. First we had to make some stuffed animals. We used six specially designed sets of three or four animals each (three cats, three dogs, three octopuses, four elephants, four snails and four turtles). The animals within each set were identical except for the eyes, which varied with respect to the size, color and presence of sclera. © 2015 The New York Times Company

Keyword: Emotions
Link ID: 21191 - Posted: 07.20.2015

By THE EDITORIAL BOARD Scientific research has a gender gap, and not just among humans. In many disciplines, the animals used to study diseases and drugs are overwhelmingly male, which may significantly reduce the reliability of research and lead to drugs that won’t work in half the population. A new study published in the journal Nature Neuroscience suggests that research done on male animals may not hold up for women. Its authors reported that hypersensitivity to pain works differently in male and female mice. For males, immune cells called microglia appear to be required for pain hypersensitivity, and inhibiting their function also relieves the pain. But in female mice, different cells are involved, and targeting the microglia has no effect. If these differences occur in mice, they may occur in humans too. This means a pain drug targeting microglia might appear to work in male mice, but wouldn’t work on women. Failure to consider gender in research is very much the norm. According to one analysis of scientific studies that were published in 2009, male animals outnumbered females 5.5 to 1 in neuroscience, 5 to 1 in pharmacology, and 3.7 to 1 in physiology. Only 45 percent of animal studies involving depression or anxiety and only 38 percent involving strokes used females, even though these conditions are more common in women. In 1994, the National Institutes of Health confronted gender imbalance in clinical drug trials and began requiring that women and minorities be included in clinical studies; women now make up around half of clinical trial participants. In June, the N.I.H. announced that it would begin requiring researchers to take gender into account in preclinical research on animals as well. © 2015 The New York Times Company

Keyword: Sexual Behavior
Link ID: 21188 - Posted: 07.20.2015