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* Electronic training collars present welfare risk to pet dogs

The research, conducted by animal behaviour specialists at the University of Lincoln, UK, indicates that, in the sample of dogs studied, there are greater welfare concerns around the use of so-called “shock collars” than with positive reward-based training. The results have been published in the peer-reviewed scientific journal PLOS One. There are arguments for and against the use of electronic training collars (or e-collars), with groups on both sides having a real concern about dog welfare and wanting to do what is best for their pet. Nevertheless, limited studies have been conducted on the use of e-collars in the pet population. Academics at the University of Lincoln investigated the performance and welfare consequences of training dogs in the field with manually operated electronic devices. The research followed a preliminary study using a small sample of dogs that had largely been referred for training because of chasing sheep. Results showed changes in dogs’ behaviour during training, which were consistent with pain or aversion, as well as increased salivary cortisol indicating increased arousal. However, these trainers did not follow training guidelines published by collar manufacturers so a larger study involving industry approved trainers was conducted to assess if training collars can be effectively used to improve obedience without compromising dog welfare. The new study involved 63 pet dogs referred for poor recall and related problems, including livestock worrying, which are the main reasons for collar use in the UK. The dogs were split into three groups — one using e-collars and two as control groups. Trainers used lower settings with a pre-warning function and behavioural responses were less marked than during the preliminary study. Despite this, dogs trained with e-collars showed behavioural changes that were consistent with a negative response. These included showing more signs of tension, more yawning and less time engaged in environmental interaction than the control dogs.

Following training most owners reported improvements in their dog’s problem behaviour. Owners of dogs trained using e-collars were, however, less confident of applying the training approach demonstrated. These findings indicate that there is no consistent benefit to be gained from e-collar training, but greater welfare concerns compared with positive reward-based training. Lead author Jonathan Cooper, Professor of Animal Behaviour and Welfare at the University of Lincoln’s School of Life Sciences, said: “e-collar training did not result in a substantially superior response to training in comparison to similarly experienced trainers who do not use e-collars to improve recall and control chasing behaviour. Accordingly, it seems that the routine use of e-collars even in accordance with best practice, as suggested by collar manufacturers, presents a risk to the well-being of pet dogs. The scale of this risk would be expected to be increased when practice falls outside of this ideal.”

http://www.sciencedaily.com/  Science Daily

http://www.sciencedaily.com/releases/2014/09/140908083344.htm  Original web page at Science Daily

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Fish-kill method questioned

Common anaesthetic not the most humane option for zebrafish euthanasia, say studies. The anaesthetic MS-222, which can be added to tanks to cause overdose, seems to distress the fish, two separate studies have shown. The studies’ authors propose that alternative anaesthetics or methods should be used instead. “These two studies — carried out independently — use different methodologies to reach the same conclusion: zebrafish detect and avoid MS-222 in the water,” says Stewart Owen, a senior environmental scientist at AstraZeneca’s Brixham Environmental Laboratory in Brixham, UK, and a co-author of one of the studies. “As this is a clear aversive response, as a humane choice, one would no longer use this agent for routine zebrafish anaesthesia.” The use of zebrafish (Danio rerio) in research has skyrocketed in recent years as scientists have sought alternatives to more controversial  animal models, such as mammals. The fish are cheap and easy to keep, and although no firm data on numbers have been collected, millions are known to be housed in laboratories around the world. Nearly all will eventually be killed. MS-222 (ethyl 3-aminobenzoate methane­sulphate, also known as TMS) is one of the agents most frequently used to kill the creatures. It is listed as an acceptable method of euthanasia by many institutions, and also by societies such as the American Veterinary Medical Association. But the study by Owen and his co-authors, published last year (G. D. Readman et al. PLoS ONE 8, e73773; 2013), and the second study, published earlier this month by Daniel Weary and his colleagues at the University of British Columbia in Vancouver, Canada (D. Wong et al. PLoS ONE 9, e88030; 2014), show that zebrafish seem to find the chemical distressing.

The research should fundamentally change the practice, say the authors of both papers. Owen’s study used video tracking to measure whether zebrafish avoided anaesthetics flowing through one side of a tank by moving to the other, untreated side. In the case of MS-222, the team found that zebrafish spent significantly more time in the untreated side than on the side containing the anaesthetic. Weary’s team allowed zebrafish to first spend time in either a light or a dark section of a tank, and then exposed them to MS-222 on their preferred side, the light side. After exposure to the anaesthetic, all but one of 17 fish in the study spent less time on the light side, and nine completely avoided it. This indicates that the fish would rather undergo discomfort — in this case, darkness — than be exposed to MS-222. “There must be something unpleasant” about MS-222 to produce such a strong signal in the experiment, says Weary, because fish do not avoid many other harmful chemicals to such an extent. “The results are pretty clear,” he adds. “We’re at a stage where it is a matter of getting policy-makers and researchers to think about this and to rethink the procedures.” There is growing debate over the most humane methods of killing laboratory mammals, with rodent euthanasia coming under increased scrutiny. Fish euthanasia has so far attracted less attention. “I think of fish welfare as being 10 to 20 years behind mammal welfare,” says Lynne Sneddon, who studies welfare in fish and is director of bioveterinary science at the University of Liverpool, UK. Sneddon says the two papers convincingly show that the use of MS-222 to kill zebrafish should probably be avoided. But she notes that there are significant differences between species — data on zebrafish should not be generalized to other laboratory fish, such as salmonids, for example — and therefore cautions against banning its use in the animals entirely.

Zoltan Varga, director of the Zebrafish International Resource Center at the University of Oregon in Eugene, also cautions against abandoning MS-222 because the optimal method of killing will depend heavily on the individual experiment and set-up. “A choice of anaesthetics is critical, as there is a range of reactions possible and we need to administer drugs that address any situation,” he says. In some cases, this could be MS-222. There is not enough evidence to know which is the most humane method, and opinions differ. Owen suggests using the anaesthetic etomidate, which is cheaper than MS-222 (US$0.15 per litre compared with $0.23 per litre of working solution) and which seemed to be less aversive in his tests. Weary’s research suggests clove oil as another cheap alternative. Varga favours ‘hypothermal shock’ — in which the zebrafish, a tropical species, are rapidly cooled. This method is illegal in the United Kingdom owing to concerns that ice may damage fish tissue while the animals are still conscious. As the number of fish experiments continues to rise — they are the second most popular research species in the United Kingdom — the question grows in importance. “We must have the patience to allow the zebrafish field research time to critically explore what the best — that is, most humane — standards are,” says Varga. “We can neither infer these standards from human experience nor from the guidelines and regulations already established for other laboratory organisms.”

http://www.nature.com/news/index.html  Nature

March 18, 2014

http://www.nature.com/news/fish-kill-method-questioned-1.14768  Original web page at Nature

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Dogs recognize familiar faces from images

So far the specialized skill for recognizing facial features holistically has been assumed to be a quality that only humans and possibly primates possess. Although it’s well known, that faces and eye contact play an important role in the communication between dogs and humans, this was the first study, where facial recognition of dogs was investigated with eye movement tracking. Typically animals’ ability to discriminate different individuals has been studied by training the animals to discriminate photographs of familiar and strange individuals. The researchers, led by Professor Outi Vainio at the University of Helsinki, tested dogs’ spontaneous behavior towards images — if the dogs are not trained to recognize faces are they able to see faces in the images and do they naturally look at familiar and strange faces differently? “Dogs were trained to lie still during the image presentation and to perform the task independently. Dogs seemed to experience the task rewarding, because they were very eager to participate” says professor Vainio. Dogs’ eye movements were measured while they watched facial images of familiar humans and dogs (e.g. dog’s owner and another dog from the same family) being displayed on the computer screen. As a comparison, the dogs were shown facial images from dogs and humans that the dogs had never met.

The results indicate that dogs were able to perceive faces in the images. Dogs looked at images of dogs longer than images of humans, regardless of the familiarity of the faces presented in the images. This corresponds to a previous study by Professor Vainio’s research group, where it was found that dogs prefer viewing conspecific faces over human faces. Dogs fixed their gaze more often on familiar faces and eyes rather than strange ones, i.e. dogs scanned familiar faces more thoroughly. In addition, part of the images was presented in inverted forms i.e. upside-down. The inverted faces were presented because their physical properties correspond to normal upright facial images e.g. same colors, contrasts, shapes. It’s known that the human brain process upside-down images in a different way than normal facial images. Thus far, it had not been studied how dogs gaze at inverted or familiar faces. Dogs viewed upright faces as long as inverted faces, but they gazed more at the eye area of upright faces, just like humans. This study shows that the gazing behavior of dogs is not only following the physical properties of images, but also the information presented in the image and its semantic meaning. Dogs are able to see faces in the images and they differentiate familiar and strange faces from each other. These results indicate that dogs might have facial recognition skills, similar to humans.

Science Daily
January 21, 2014

Original web page at Science Daily

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Lemur babies of older moms less likely to get hurt

A long-term study of aggression in lemurs finds that infants born to older mothers are less likely to get hurt than those born to younger mothers. The researchers base their findings on an analysis of detailed medical records for more than 240 ring-tailed lemurs — cat-sized primates with long black-and-white banded tails — that were monitored daily from infancy to adulthood over a 35-year period at the Duke Lemur Center in North Carolina. The results suggest that infants born to older mothers are less likely to get bitten. It may be that older moms are better at fending off attackers or protecting their infants during fights, say researchers at Duke University and the National Center for Scientific Research in Montpellier, France. The study appeared online in the December 18 issue of the journal PLOS ONE. In most animal societies, males are the more aggressive sex. But in lemurs, females can be bullies too, explained co-author Marie Charpentier of the National Center for Scientific Research in France. Female lemurs compete with one another for first dibs on food and chase away males at mealtimes, sometimes lunging or snapping at each other with their sharp canine teeth.

To tease out the factors that influence who gets hurt when ring-tailed lemurs tussle, Charpentier and Christine Drea of Duke University combed the animals’ medical records for evidence of bite wounds. Animals at the Duke Lemur Center live outdoors for much of the year in large forested enclosures ranging in size from 1.5 to 14 acres. In these natural habitat enclosures, ring-tailed lemurs live in mixed groups of males and females who are free to forage, interact, play and move around as they would in the wild, providing a unique opportunity to study lemur social dynamics. Any victims of serial bullying are removed from the group to prevent additional injuries, and all wounds are recorded and treated by veterinarians. As a result, infant mortality for ring-tailed lemurs at the Lemur Center overall is about half of what it often is in the wild. Of the 237 ring-tailed lemur babies born at the Duke Lemur Center between 1971 and 2006, 15 were bitten before their first birthday, all of whom died from their wounds. The researchers examined a range of possible risk factors that might influence how the infants fared, including sex, weight, genetic diversity, group size, and whether the infant was a twin or a singleton. Of all the factors studied, the one that had the most significant impact on infant injury and survival rates was the age of the mother.

Infants that avoided injury were born to mothers who were two years older on average than the mothers of infants that were badly bitten. The results held up even when the mothers were first-time moms. “Whether the mother had had a kid before didn’t matter,” Drea said. The records don’t reveal who the perpetrators were, but in a separate behavioral study, the authors found that females — some of them related to the victims as sisters and aunts — were responsible for some of the biting. In some animal species, males are known to attack and kill the infants of nursing moms to bring the females back into heat. But the same mechanism is unlikely to be at work in ring-tailed lemurs because these animals only breed once a season, and because females wean their infants before the next breeding season begins. “Even if a female stopped nursing prematurely due to the death of an infant, she wouldn’t be ready to breed again until the next season anyway,” Drea said. Other researchers have found injured infants clinging to their mothers at the time of attack, rather than venturing out on their own. This suggests that the mother, not the baby, may be the intended target and infant injuries are a byproduct of skirmishes between adults.

Additional research is needed to determine why maternal age improves infant survival, but it is possible that older moms are better at protecting their infants or are less likely to pick fights. Older females could also be less frequent targets of aggression from their female peers. The study illustrates one of the ways that female aggression takes its toll, Drea added. For young female lemurs in particular, fighting for their place in the pecking order comes at a cost to their infants. “Female lemurs are more dominant and aggressive than females in other species, and that puts their kids at risk,” Drea said.

Science Daily
January 21, 2014

Original web page at Science Daily

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How horses can teach humans communication skills, kindness

A nudge from the nose of a free-roaming zebra, or towering, 2,500-pound Clydesdale draft horse, might send others running. But Lauren Burke, a graduate student at Case Western Reserve University’s social work school, instead extends a curved hand to return the equine “hello.” In her required social work field placement, Burke spent the last 18 months at Spirit of Leadership at the Pebble Ledge Ranch in Novelty, Ohio, learning to communicate with horses (and a zebra), becoming “one with the herd” and teaching others how to do the same in an experiential learning with horses program that inspires self-discovery. By developing a sensitivity to the body language of horses, explained Jacalyn Lowe Stevenson, Spirit of Leadership founder and president and Burke’s supervisor, humans may better understand nonverbal communication in each other — the goal of which is to enhance the group dynamic, from the corporate boardroom to the family dining room table. Among corporate and nonprofit clients are ArcelorMittal, Lubrizol, Humana, University Hospitals of Cleveland, Cleveland Metroparks Zoo, Ohio Mutual Insurance, the Cleveland Rape Crisis Center, the American Heart Association, Bratenahl Police, Israeli Defense Force, and U.S. military veterans. Understanding a horse’s non-verbal body language and, in turn, being accepted as a member of the herd is part of a new approach Stevenson pioneered and developed, called Equine Guided Coaching and Experiential Learning with Horses.

Stevenson’s work and organization has inspired Burke, who wants to use animal therapy and personal discovery (particularly horses) in her social work profession. Stevenson, MSSA, an adjunct instructor at the Jack, Joseph and Morton Mandel School of Applied Social Sciences and the Weatherhead School of Management, uses horses as the center of therapy that promotes self-discovery, innovation and positive relationships. At Spirit of Leadership, Burke learned how to advance the program’s vision as a catalyst for leadership excellence, team performance and organizational spirit — all inspired by horses. Burke has worked directly with clients, has helped plan an international conference on equine-guided coaching, traveled to Atlanta, Baltimore and Lexington, Ky., to establish herd relationships and work with corporate clients in each city. Of course, she’s also had to experience the more mundane, cleaning barns and feeding horses. Before clients are introduced to the horses, Burke begins with a 15-minute lesson in nonverbal horse communications — the meaning of ear positioning, swishing tails, and handling a nose-to-nose welcome. No one rides the horses; it is about engaging in a relationship with the horses and team members. Burke teaches clients how to go from greeting the horses, to creating respect and trust to leading a horse through an obstacle course, called the “Field of Possibilities.” By doing so, clients achieve skills in working as a team.

This unique experiential learning evolved from Stevenson’s counseling sessions on her 80-acre ranch. She noticed clients always stopped to talk to horses freely roaming the pastures and woods on her Western Reserve Land Conservancy Trust property along the Chagrin River. The attraction to the horses inspired Stevenson to put chairs in the field and conduct client sessions among the grazing horses. Clients began to notice how the horses responded to their attitudes. The horses would approach if they sensed people were excited to see them and passionate about what they were discussing or retreated if they sensed disinterest. That sent a powerful message to clients, Stevenson said. The excitement demonstrated to clients what they were passionate about, and goals they wanted to accomplish. They also become aware of their inner strengths. Stevenson has incorporated a number of Case Western Reserve researched and developed theories by faculty at the management school: David Cooperrider’s appreciative inquiry (building from individual or organizational strengths), Richard Boyatzis’ emotional intelligence (how skillful people are with interacting with each other) and David Kolb’s style of learning (learning by experiencing). The approach is based on the belief that humans and horses share a natural connection. In fact, Burke said, horses are a metaphor for humans who, like a herd, once lived and worked together, with each member contributing to maintaining the tribe. And, like an isolated and lonely human, horses also suffer emotional and physical problems when separated from their herds, she said.

According to Stevenson, horses developed a herd life over the last 60 million years for survival by drawing on each other’s strength, moving toward that which is positive and adapting to environmental changes. “Horses have set such good examples for how to live my life as a leader, family member, friend, potentially a wife and mother, and how to be a good social worker who embodies the profession,” Burke said. Burke and social work grad student Casey Dawson were the first to have a field placement at Spirit of Leadership. Each had to pass several requirements Stevenson set, including a love of — and experience working with — horses in their natural setting and a strong desire to help people. Burke has been riding since age 4 on her family’s rural Pennsylvanian farm, a home to six horses. After graduating from the University of Findlay as a double major in social work and a western equestrian program, Burke enrolled at the Mandel School to pursue a master’s of science in social administration degree. The opportunity for field placement at Stevenson’s farm was a major attraction. “My career goal,” said Burke, who graduates this semester, “is to take everything that I’ve learned from Jackie and the horses, and my educational experiences to set up an equine-based facility that focuses on animal-assisted therapy to promote personal discovery, growth and learning.”

Science Daily
January 7, 2014

Original web page at Science Daily

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Chimpanzees are rational, not conformists, researchers find

Chimpanzees are sensitive to social influences but they maintain their own strategy to solve a problem rather than conform to what the majority of group members are doing. However, chimpanzees do change their strategy when they can obtain greater rewards, MPI researchers found. The study was published in PLOS ONE on November 28, 2013. Chimpanzees are known for their curious nature. They show a rich palette of learning behaviour, both individually and socially. But they are also rather hesitant to abandon their personal preferences, even when that familiar behaviour becomes extremely ineffective. Under which circumstances would chimpanzees flexibly adjust their behaviour? Edwin van Leeuwen and colleagues from the MPI’s for Psycholinguistics and Evolutionary Anthropology conducted a series of experiments in Germany and Zambia to answer this question. The researchers studied 16 captive chimpanzees at the Wolfgang Kohler Primate Research Center in Germany (Leipzig) and 12 semi-wild chimpanzees at the Chimfunshi Wildlife Orphanage Trust, a sanctuary that houses more than a hundred chimpanzees under nearly natural conditions in the north-western part of Zambia. Chimpanzees were trained on two different vending machines. A minority of the group was made familiar with one machine and the majority of group members with the other machine. Wooden balls were thrown into their enclosure; the chimpanzees could insert these balls into the machines to receive one peanut for each ball.

Van Leeuwen and his colleagues first aimed to replicate previous research and looked whether the chimpanzees in the minority group would change their behaviour toward using the vending machine that the majority of group members used. However, neither the German nor the Zambian chimpanzees gave up their strategy to join the majority. In the second study, the profitability of the vending machines was changed so that the vending machine that the minority used became more profitable, now spitting out five rewards for every ball inserted. Over time, the majority chimpanzees observed that the minority chimpanzees received more peanuts for the same effort and all but one gradually switched to using this more profitable machine. “Where chimpanzees do not readily change their behaviour under majority influences, they do change their behaviour when they can maximise their payoffs,” Van Leeuwen says. “We conclude that chimpanzees may prefer persevering in successful and familiar strategies over adopting the equally effective strategy of the majority, but that chimpanzees find sufficient incentive in changing their behaviour when they can obtain higher rewards somewhere else.” “So, it’s peanuts over popularity” he jokingly adds. The researchers emphasise that these results may be dependent upon the specific trade-offs that were created by the experimental design and that chimpanzees could act differently under the pressures of life in the wild. Van Leeuwen: “Conformity could still be a process guiding chimpanzees’ behaviour. Chimpanzee females, for instance, disperse to other groups in the wild. For these females, it is of vital importance to integrate into the new group. Conformity to local (foraging) customs might help them to achieve this integration.”

Science Daily
January 7, 2014

Original web page at Science Daily

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Crows are no bird-brains: Neurobiologists investigate neuronal basis of crows’ intelligence

Scientists have long suspected that corvids — the family of birds including ravens, crows and magpies — are highly intelligent. Now, Tübingen neurobiologists Lena Veit und Professor Andreas Nieder have demonstrated how the brains of crows produce intelligent behavior when the birds have to make strategic decisions. Their results are published in the latest edition of Nature Communications. Crows are no bird-brains. Behavioral biologists have even called them “feathered primates” because the birds make and use tools, are able to remember large numbers of feeding sites, and plan their social behavior according to what other members of their group do. This high level of intelligence might seem surprising because birds’ brains are constructed in a fundamentally different way from those of mammals, including primates — which are usually used to investigate these behaviors. The Tübingen researchers are the first to investigate the brain physiology of crows’ intelligent behavior. They trained crows to carry out memory tests on a computer. The crows were shown an image and had to remember it. Shortly afterwards, they had to select one of two test images on a touchscreen with their beaks based on a switching behavioral rules. One of the test images was identical to the first image, the other different. Sometimes the rule of the game was to select the same image, and sometimes it was to select the different one. The crows were able to carry out both tasks and to switch between them as appropriate. That demonstrates a high level of concentration and mental flexibility which few animal species can manage — and which is an effort even for humans.

The crows were quickly able to carry out these tasks even when given new sets of images. The researchers observed neuronal activity in the nidopallium caudolaterale, a brain region associated with the highest levels of cognition in birds. One group of nerve cells responded exclusively when the crows had to choose the same image — while another group of cells always responded when they were operating on the “different image” rule. By observing this cell activity, the researchers were often able to predict which rule the crow was following even before it made its choice. The study published in Nature Communications provides valuable insights into the parallel evolution of intelligent behavior. “Many functions are realized differently in birds because a long evolutionary history separates us from these direct descendants of the dinosaurs,” says Lena Veit. “This means that bird brains can show us an alternative solution out of how intelligent behavior is produced with a different anatomy.” Crows and primates have different brains, but the cells regulating decision-making are very similar. They represent a general principle which has re-emerged throughout the history of evolution. “Just as we can draw valid conclusions on aerodynamics from a comparison of the very differently constructed wings of birds and bats, here we are able to draw conclusions about how the brain works by investigating the functional similarities and differences of the relevant brain areas in avian and mammalian brains,” says Professor Andreas Nieder.

Science Daily
December 10, 2013

Original web page at Science Daily

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Fences divide lion conservationists

Times are grim for the king of the beasts. Roughly 35,000 African lions roam the savannahs, down from more than 100,000 half a century ago, thanks to habitat loss, declining numbers of prey animals and killing by humans. One study estimated that fewer than 50 lions (Panthera leo) live in Nigeria and reported no sign of the animal in the Republic of the Congo, Ghana or Côte d’Ivoire. Now a king-sized controversy is brewing over a proposal to shore up lion populations before it is too late. A prominent lion researcher has called for limiting conflict between humans and lions by erecting fences around reserves containing wild lions. The idea has split scientists, with those opposed to the idea arguing that fences could do more harm than good. The ensuing debate has also laid bare fundamental differences of opinion about how to preserve lions and other species, and raised concerns that a key challenge to lion conservation — lack of funds — is being ignored while scientists trade jabs about fences. When he began the research that kicked off the furore, Craig Packer of the University of Minnesota in St Paul, who studies lions at Tanzania’s Serengeti National Park, intended to determine only the cost of conserving lions. But something more provocative emerged from his data. In work reported earlier this year in Ecology Letters, he and 57 co-authors calculated lion densities at 42 African reserves and found, Packer says, that the only variables that matter for density are “dollars and fence — nothing else”. He adds that “the fence has a very profound, powerful effect”, because it prevents lions from preying on livestock and people, meaning fewer lions are killed in retaliation. Packer would like to see fences around even some of the largest protected areas such as Tanzania’s 47,000-square-kilometre Selous Game Reserve.

But the paper triggered heated discussion, both online and at meetings, leading four months later to the publication of a response signed by 55 researchers. They argue that Packer’s analysis is wrong to use lion population density as its sole yardstick. By that measurement, they say, a dense population of several dozen lions in a small reserve is a success, whereas a large reserve containing 600 lions is a failure. When the authors restricted their study to lion populations whose density did not exceed the land’s capacity to support them and controlled for a reserve’s management budget, they found no relationship between fencing and density. That study’s first author, Scott Creel of Montana State University in Bozeman, says that although fencing is beneficial at small, well-funded reserves, most of Africa’s wild lions live in large reserves with modest funding. “If you build a fence and spend a lot of money, you can maintain a lot of lions within it,” Creel says. “The problem is, we don’t know very much about how fencing works in enormous ecosystems that have smaller budgets.” Packer’s side responded with its own reanalysis. Rather than eliminating the super-saturated lion populations from the equation, the researchers assigned them a density of 100%. Once again, they found the presence of fencing to be the strongest predictor of lion density, Packer says. Creel counters that the reanalysis shows no impact of fencing on population size, so it is still unclear whether fences would have a protective effect for large, natural ecosystems.

Other researchers are split over which argument is more convincing. Matt Hayward of Bangor University, UK, who co-authored a book about conservation fencing, says that both sides score points, and, in any case, the disagreement goes beyond statistics to “a very passionate philosophical debate”. He adds that “some people are saying, ‘Look, we don’t want any fences in the landscape. We want to keep wildlife moving wherever it wants to.’” And rightfully so, many say: ill-conceived fences could hinder animals’ search for food during tough times, as well as leading to losses of wide-ranging species, such as cheetahs and wild dogs, that need big expanses of land. “Is saving lions above everything else?” asks Creel’s co-author Nathalie Pettorelli of London’s Institute of Zoology. “You cannot manage a landscape by looking at just one species.” Bush-meat snares made with wire stripped from fences pose another risk. These often catch and may kill lions, elephants and other species, and have been a serious problem in places such as Zambia. But Packer says that a properly built fence, although costly, would not support snaring. And he argues that the opposition’s goal of maintaining open landscapes is deeply impractical in the face of Africa’s burgeoning human population. He has already tried to drum up support for fencing with African officials, and he also hopes donors with an interest in conservation projects, such as the World Bank, might fund a fence around a large reserve. Meanwhile, many of those who oppose the idea would rather see money poured into proven approaches such as law enforcement. But the two camps also share plenty of common ground. Creel’s co-authors say that fences can be effective, and Packer’s allies agree fences are inappropriate for many areas. While scientists wrangle over the issue, “lions are disappearing faster than ever”, says Philipp Henschel, a lion specialist for the conservation group Panthera, who signed Creel’s paper . The community should “concentrate on the one thing that both sides agree on: that effective lion conservation will require substantially more funding than is currently made available”.

Nature
December 10, 2013

Original web page at Nature

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Biologists find an evolutionary Facebook for monkeys and apes

Why do the faces of some primates contain so many different colors — black, blue, red, orange and white — that are mixed in all kinds of combinations and often striking patterns while other primate faces are quite plain? UCLA biologists reported last year on the evolution of 129 primate faces in species from Central and South America. This research team now reports on the faces of 139 Old World African and Asian primate species that have been diversifying over some 25 million years. With these Old World monkeys and apes, the species that are more social have more complex facial patterns, the biologists found. Species that have smaller group sizes tend to have simpler faces with fewer colors, perhaps because the presence of more color patches in the face results in greater potential for facial variation across individuals within species. This variation could aid in identification, which may be a more difficult task in larger groups. Species that live in the same habitat with other closely related species tend to have more complex facial patterns, suggesting that complex faces may also aid in species recognition, the life scientists found.

“Humans are crazy for Facebook, but our research suggests that primates have been relying on the face to tell friends from competitors for the last 50 million years and that social pressures have guided the evolution of the enormous diversity of faces we see across the group today,” said Michael Alfaro, an associate professor of ecology and evolutionary biology in the UCLA College of Letters and Science and senior author of the study. “Faces are really important to how monkeys and apes can tell one another apart,” he said. “We think the color patterns have to do both with the importance of telling individuals of your own species apart from closely related species and for social communication among members of the same species.” Most Old World monkeys and apes are social, and some species, like the mandrills, can live in groups with up to 800 members, said co-author Jessica Lynch Alfaro, an adjunct assistant professor in the UCLA Department of Anthropology and UCLA’s Institute for Society and Genetics. At the other extreme are solitary species, like the orangutans. In most orangutan populations, adult males travel and sleep alone, and females are accompanied only by their young, she said. Some primates, like chimpanzees, have “fission-fusion societies,” where they break up into small sub-groups and come together occasionally in very large communities. Others, like the hamadryas baboons, have tiered societies with harems, clans, bands and troops, she said.

“Our research suggests increasing group size puts more pressure on the evolution of coloration across different sub-regions of the face,” Michael Alfaro said. This allows members of a species to have “more communication avenues, a greater repertoire of facial vocabulary, which is advantageous if you’re interacting with many members of your species,” he said. The research, federally funded by the National Science Foundation and supported through a postdoctoral fellowship from the UCLA Institute for Society and Genetics, was published Nov. 11 in the journal Nature Communications. Lead study author Sharlene Santana used photographs of primate faces for her analysis and devised a new method to quantify the complex patterns of primate faces. She divided each face into several regions; classified the color of each part of the face, including the hair and skin; and assigned a score based on the total number of different colors across the facial regions. This numerical score is called the “facial complexity” score. The life scientists then studied how the complexity scores of primate faces were related to primates’ social systems. The habitat where species live presents many potential pressures that could have influenced the evolution of facial coloration. To assess how facial colors are related to physical environments, the researchers analyzed environmental variables such as geographic location, canopy density, rainfall and temperature. They also used statistical methods that took into account the evolutionary history and relationships among the primate groups to better understand the evolution of facial diversity and complexity.

While facial complexity was related to social variables, such as group size and the number of closely related species in the same habitat, facial pigmentation was best explained by ecological and spatial factors. Where a species lives is a good predictor of its degree of facial pigmentation — how light or dark the face is. “Our map shows clearly the geographic trend in Africa of primate faces getting darker nearer to the equator and lighter as we move farther away from the equator,” Lynch Alfaro said. “This is the same trend we see on an intra-species level for human skin pigmentation around the globe.” Species living in more tropical and more densely forested habitats also tend to have darker, more pigmented faces. But the complexity of facial color patterns is not related to habitat type. “We found that for African primates, faces tend to be light or dark depending on how open or closed the habitat is and on how much light the habitat receives,” Alfaro said. “We also found that no matter where you live, if your species has a large social group, then your face tends to be more complex. It will tend to be darker and more complex if you’re in a closed habitat in a large social group, and it will tend to be lighter and more complex if you’re in an open habitat with a large social group. Darkness or lightness is explained by geography and habitat type. Facial complexity is better explained by the size of your social group.” In their research on primates from Central and South America published last year, the scientists were surprised to find a different pattern. For these primates, species that lived in larger groups had more plain facial patterns.

“We expected to find similar trends across all primate radiations — that is, that the faces of highly social species would have more complex patterning,” said Santana, who conducted the research as a postdoctoral fellow with the UCLA Department of Ecology and Evolutionary Biology and UCLA’s Institute for Society and Genetics and who is now an assistant professor at the University of Washington and curator of mammals at the Burke Museum of Natural History and Culture. “We were surprised by the results in our original study on neotropical (Central and South American) primates.” In the new study, they did find the predicted trends, but they also found differences across primate groups — differences they said they found intriguing. Are primate groups using their faces differently? “In the present study, great apes had significantly lower facial complexity compared to monkeys,” Lynch Alfaro said. “This may be because apes are using their faces for highly complex facial expressions and these expressions would be obscured by more complex facial color patterns. There may be competing pressures for and against facial pattern complexity in large groups, and different lineages may solve this problem in different ways.”

“Our research shows that being more or less social is a key explanation for the facial diversity that we see,” Alfaro said. “Ecology is also important, such as camouflage and thermal regulation, but our research suggests that faces have evolved along with the diversity of social behaviors in primates, and that is the big cause of facial diversity.” Alfaro and his colleagues serve as “evolutionary detectives,” asking what factors produced the patterns of species richness and diversity of traits. “When evolutionary biologists see these striking patterns of richness, we want to understand the underlying causes,” he said. Human faces were not part of the analysis, although humans also belong to the clade catarrhini, which includes Old World monkeys and apes. Andrew Noonan, a former UCLA undergraduate student who conducted research in Alfaros laboratory, was also a co-author of this research.

Science Daily
December 10, 2013

Original web page at Science Daily

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How pigeons may smell their way home

Homing pigeons, like other birds, are extraordinary navigators, but how they manage to find their way back to their lofts is still debated. To navigate, birds require a ‘map’ (to tell them home is south, for example) and a ‘compass’ (to tell them where south is), with the sun and the earth’s magnetic field being the preferred compass systems. A new paper provides evidence that the information pigeons use as a map is in fact available in the atmosphere: odors and winds allow them to find their way home. he results are now published in Biogeosciences, an open access journal of the European Geosciences Union (EGU). Experiments over the past 40 years have shown that homing pigeons get disoriented when their sense of smell is impaired or when they don’t have access to natural winds at their home site. But many researchers were not convinced that wind-borne odors could provide the map pigeons need to navigate. Now, Hans Wallraff of the Max Planck Institute for Ornithology in Seewiesen, Germany, has shown that the atmosphere does contain the necessary information to help pigeons find their way home. In previous research, Wallraff collected air samples at over 90 sites within a 200 km radius around a former pigeon loft near Würzburg in southern Germany. The samples revealed that the ratios among certain ‘volatile organic compounds’ (chemicals that can be a source of scents and odors) in the atmosphere increase or decrease along specific directions. “For instance, the percentage of compound A in the sum A+B or A+B+C+D increases the farther one moves from north to south,” Wallraff explains.

These changes in compound ratios translate into changes in perceived smell. But a pigeon that has never left its loft does not know in what directions what changes occur — unless it has been exposed to winds at its home site. At home, a bird is thought to associate certain smells with particular wind directions. “If the percentage of compound A increases with southerly winds, a pigeon living in a loft in Würzburg learns this wind-correlated increase. If released at a site some 100 km south of home, the bird smells that the ratio of compound A is above what it is on average at its loft and flies north,” Wallraff explains. To use an analogy, a person in Munich could smell an Alpine breeze when there is wind blowing from the south. When displaced closer to the mountains, they would detect a strong Alpine scent and remember that, at home, that smell is associated with southerly winds: the person would know that, roughly, they needed to travel north to find home. But this explanation of how pigeons might use wind-borne odors to find their loft was just a hypothesis: Wallraff still needed to prove that the atmosphere does indeed contain the basis of the map system pigeons need to navigate. In the new Biogeosciences paper, he develops a model showing that ‘virtual pigeons’ with only knowledge of winds and odors at home, can find their way back to their lofts by using real atmospheric data. “My virtual pigeons served as tools to select those volatile compounds whose spatial distributions, combined with variations dependent on wind direction, were most suitable for homeward navigation,” explains Wallraff.

The model uses an iterative approach to imitate animal evolution by introducing random mutations in the virtual pigeons, making them most sensitive to those volatile compounds that are most effective for navigation. By selecting the best mutations in the course of thousands of generations, the model creates virtual pigeons capable of finding their bearings as well as real pigeons, showing that even inexperienced birds could use atmospheric information for navigation. The findings present a missing piece in the puzzle of homing pigeon navigation, confirming that winds and odors can indeed work as a map system. “Work with real pigeons was the beginning of the story. In this research, I wanted to find out whether and in what way the chemical atmosphere fulfills the demands for avian navigation. Eventually, to identify the chemical compounds birds actually use for home-finding, we will need real birds again. But this is far in the future.”

Science Daily
November 26, 2013

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Monkey that purrs like a cat is among new species discovered in Amazon rainforest

At least 441 new species of animals and plants have been discovered over a four year period in the vast, underexplored rainforest of the Amazon, including a monkey that purrs like a cat. Found between 2010 and 2013, the species include a flame-patterned lizard, a thumbnail-sized frog, a vegetarian piranha, a brightly coloured snake, and a beautiful pink orchid, according to World Wildlife Fund (WWF). Discovered by a group of scientists and compiled by WWF, the new species number 258 plants, 84 fish, 58 amphibians, 22 reptiles, 18 birds and one mammal. This total does not include countless discoveries of insects and other invertebrates. “These species form a unique natural heritage that we need to conserve. This means protecting their home — the amazing Amazon rainforest — which is under threat from deforestation and dam development,” said Claudio Maretti, Leader of Living Amazon Initiative, WWF. Some of the most remarkable species outlined in the report include:

• Flame-patterned lizard: This beautiful lizard was found from the hatchlings of eggs collected by scientists in the Colombian Amazon. An elusive species, Cercosaura hypnoides, has not been seen in the wild since the original eggs were collected, raising the prospect that it could potentially be endangered.
• Thumbnail-sized frog: This amphibian is already believed to be highly endangered. In fact, its Latin name, Allobates amissibilis, meaning “that may be lost,” alludes to this as the area where it thrives could soon be opened to tourism. This is now the third Allobates species found in Guyana.
• Vegetarian piranha: This new species of piranha, Tometes camunani, can span 20 inches wide and weigh up to 9 pounds, and is strictly herbivorous. The freshwater fish inhabits rocky rapids associated with seedlings of plants that grow among the rocks, its main source of food. Tometes is described from the upper drainages of the Trombetas River basin, Para, Brazilian Amazon.
• A brightly coloured snake from the “Lost World”: Found in the mountains of Guyana, this brightly-colored snake species was named Chironius challenger after Arthur C. Doyle’s fictional character Professor George Edward Challenger in the novel, The Lost World.
• A beautiful pink orchid: Among the new plant species are a large number of new orchid species, including this splendid pink species, Sobralia imavieirae, officially described by scientists from Roraima in the Brazilian Amazon.
Caqueta titi monkey: This new species, Callicebus caquetensis, is one of about 20 species of titi monkey, which all live in the Amazon basin. The babies have an endearing trait, “When they feel very content they purr towards each other,” explained scientist Thomas Defler.

Many of the new discoveries are believed to be endemic to the Amazon rainforest and are found nowhere else in the world. This makes them even more vulnerable to rainforest destruction that occurs every minute across the Amazon. “Compiling and updating data on new species discovered in the vast extension of the Amazon over the last four years has shown us just how important the region is for humanity and how fundamentally important it is to research it, understand it and conserve it. The destruction of these ecosystems is threatening biodiversity and the services it provides to societies and economies. We cannot allow this natural heritage to be lost forever,” Maretti said.

Science Daily
November 12, 2013

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Climate change has silver lining for grizzly bears

Global warming and forest disturbances may have a silver lining for threatened species of grizzly bears in Alberta, Canada. In a 10-year study that monitored 112 bears in Alberta’s Rocky Mountain region, University of Alberta biologist Scott Nielsen and his colleagues found that warmer temperatures and easier access to food associated with forest disturbances helped the grizzlies to build more body fat, known to increase the chances of successful reproduction for mothers. The resulting ‘silver spoon effect’ shows that bears born into these favourable conditions have a head-start in life, said Nielsen, an assistant professor in the U of A Department of Renewable Resources. “Understanding variations in body size helps us understand what limits grizzly populations,” Nielsen said. “We get clues about the environments that most suit grizzlies by examining basic health measures such as body size. A simple rule is, the fatter the bear, the better. Certain environments promote fatter bears. The findings, published in BMC Ecology, may help influence forest harvest designs to enhance habitat for the Alberta grizzly, which is classed by the Alberta government as a threatened species. Currently there are only about 750 of the bears in the province, half of them adults.

In years when warmer temperatures and less late winter snow brought on earlier spring conditions, the body size of bears as adults was larger. Smaller bears were found in colder and less productive environments or years that were abnormally cool. “We hypothesize that warmer temperatures in this ecosystem, especially during late winter and spring, may not be such a bad thing for grizzlies,” Nielsen said, noting that historically the range for the bears once extended as far south as Mexico and persists today even in the deserts of Mongolia. “That suggests the species won’t likely be limited by rising temperatures which would lengthen the growing season and the time needed to fatten prior to hibernation.” As well, bears that used disturbed forest habitats containing a wide variety of stand ages were healthier, Nielsen said. “The diversity of stand ages in the landscape has a positive influence on body condition because bears are better able to access a wide range of food sources.”

Science Daily
November 12, 2013

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Extra gene makes mice manic

A gene whose abnormalities have been associated with symptoms of schizophrenia, epilepsy and autism also has comparable effects when artificially duplicated in mice. Duplication of a single gene — and too much of the corresponding protein in brain cells — causes mice to have seizures and display manic-like behaviour, a study has found. But a widely used drug reversed the symptoms, suggesting that it could also help some people with hyperactivity who do not respond to common treatments. Smooth functioning at the synapses, the junctions between brain cells, is crucial to functions that control everything from social etiquette to everyday decision-making. It is increasingly thought that some neuropsychiatric disorders are caused by function of the synapses going awry, and indeed researchers have found that neuropsychiatric conditions such as schizophrenia and autism can sometimes be traced to missing or mutated copies of SHANK3, a gene that encodes one of the ‘architectural’ proteins that help to ensure that messages are relayed properly between cells. Some people with attention deficit hyperactivity disorder (ADHD), Asperger’s syndrome or schizophrenia have an extra copy of a wider region of DNA that contains SHANK3. To explore the role of SHANK3, Huda Zoghbi, a neurogeneticist at Baylor College of Medicine in Houston, Texas, and her colleagues created mice with duplicate copies of the gene. “The mouse was remarkably hyperactive, running around like mad,” says Zoghbi. But the animals did not respond to stimulant medications typically used to treat ADHD. Instead, their hyperactivity grew much worse. “That’s when we knew this was not typical ADHD,” says Zoghbi. The study is published recently in Nature. The paper is a “really good example of the importance of gene dosage”, says Thomas Insel, director of the US National Institute of Mental Health in Bethesda, Maryland. “It matters a lot whether you have no copies, one copy, two copies” or more of a given gene, he says.

In addition to hyperactivity, the mice displayed a combination of mania-like behaviours and seizures, which are indicative of a psychiatric disorder called hyperkinesia. When the researchers sifted through clinical databases, they found records of two people whose psychiatric profiles resembled those of the mice, and who also carried a duplication of SHANK3. One had bipolar disorder and epilepsy; the other had seizures and ADHD characterized by hyperactivity, poor attention and compulsive behaviour. Like the mice, this person had not responded well to amphetamines used to treat ADHD. After trying various treatments, the researchers gave the mice valproate, an anticonvulsant and mood-stabilizing drug commonly used to treat bipolar disorder and epilepsy. Remarkably, the drug reversed the psychiatric effects. The results suggest that excess SHANK3 protein drives a psychiatric syndrome that can be treated effectively. Joe Gleeson, a paediatric neurologist and geneticist at the University of California, San Diego, says that the study is “one of the first to explore, in a comprehensive way” the importance of gene dosage in mouse neurological disorders. He says that the paper addresses the underpinnings of these disorders on all fronts, from psychopharmacology to proteomics and human genomics, and notes that “the results are all in alignment”.

Nature
November 12, 2013

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To swallow or to spit? New medicines for llamas, alpacas

South American camelids, especially llamas and alpacas, are very susceptible to infections caused by endoparasites. The so-called small liver fluke (Dicrocoelium dendriticum) is particularly problematic and infections with this parasite are frequently fatal. Moreover, camelids are prone to stress and together with their tendency to spit (especially when they do not like the taste of something) this very often results in underdosing if they are given medicine to swallow. Inadequate treatment of endoparasites leads to progression of the pathological changes and can be lethal for the animals. Underdosing of antiparasitic drugs may also lead to the emergence of anthelmintic resistance. Two scientists from the Vetmeduni Vienna now report a solution. Agnes Dadak from the Institute of Pharmacology and Sonja Franz from the Clinic for Ruminants have jointly developed a palatable paste that the animals swallow willingly and that allows the administration of highly concentrated drugs in small volumes. Drugs that are already approved for use in other species but not available in a concentration appropriate for use in llamas and alpacas can be incorporated in the paste in the correct dose. To treat small liver fluke, the vets added the drug praziquantel to the paste to give a final dose of 50mg/kg body weight. This extremely high dose turns out to be exactly right for the successful treatment of the disease in camelids. Administering drugs orally to camelids has significant advantages.

Topical treatment of the animals is generally ineffective because of their thick skin, which is not easily permeated by drugs. Furthermore, many active substances cannot be provided as injections due to their chemical characteristics. “Our paste seems to be extremely useful in treating the animals. We are now working on incorporating other important drugs for use against different diseases in llamas and alpacas,” says pharmacologist Dadak. Llamas and alpacas are normally kept in herds, so it makes sense to treat the entire stock if an infection with the small liver fluke is detected. “We are happy to make our experience and scientific knowledge of camelids available to people who keep these animals, as well as to veterinary surgeons. Our development provides a scientifically sound basis for ensuring the health of the animals,” says ruminant expert Franz.

Science Daily
November 12, 2013

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Elephants know what it means to point to something, no training required

When people want to direct the attention of others, they naturally do so by pointing, starting from a very young age. Now, researchers reporting in Current Biology, a Cell Press publication, on October 10 have shown that elephants spontaneously get the gist of human pointing and can use it as a cue for finding food. That’s all the more impressive given that many great apes fail to understand pointing when it’s done for them by human caretakers, the researchers say. By showing that African elephants spontaneously understand human pointing, without any training to do so, we have shown that the ability to understand pointing is not uniquely human but has also evolved in a lineage of animal very remote from the primates,” says Richard Byrne of the University of St Andrews, noting that elephants are part of an ancient African radiation of animals, including the hyrax, golden mole, aardvark, and manatee. “What elephants share with humans is that they live in an elaborate and complex network in which support, empathy, and help for others are critical for survival. It may be only in such a society that the ability to follow pointing has adaptive value, or, more generally, elephant society may have selected for an ability to understand when others are trying to communicate with them, and they are thus able to work out what pointing is about when they see it.”

Byrne and study first author Anna Smet were studying elephants whose “day job” is taking tourists on elephant-back rides near Victoria Falls, in southern Africa. The animals were trained to follow certain vocal commands, but they weren’t accustomed to pointing. “Of course, we always hoped that our elephants would be able to learn to follow human pointing, or we’d not have carried out the experiments,” Smet says. “What really surprised us is that they did not apparently need to learn anything. Their understanding was as good on the first trial as the last, and we could find no sign of learning over the experiment.” Elephants that were more experienced with humans, or those born in captivity, were no better than less-experienced, wild-born individuals when it came to following pointing gestures. Byrne and Smet say it is possible that elephants may do something akin to pointing as a means of communicating with each other, using their long trunk. Elephants do regularly make prominent trunk gestures, but it remains to be seen whether those motions act in elephant society as “points.”

The findings help to explain how it is that humans have been able to rely on wild-caught elephants as work animals, for logging, transport, or war, for thousands of years. Elephants have a natural capacity to interact with humans even though — unlike horses, dogs, and camels — they have never been bred or domesticated for that role. Elephants seem to understand us humans in a way most other animals don’t. “Elephants are cognitively much more like us than has been realized, making them able to understand our characteristic way of indicating things in the environment by pointing,” Byrne says. “This means that pointing is not a uniquely human part of the language system.”

Science Daily
October 29, 2013

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Swifts stay airborne for six months at a time

Swifts are said to spend most of their lives airborne, but no one has ever proved this. Now, a study suggests there’s some truth to it: alpine swifts spend more than six consecutive months aloft, not even resting after migrating to north Africa following their breeding season in Europe. “Up to now, such long-lasting locomotive activity had been reported only for animals living in the sea,” says Felix Liechti of the Swiss Ornithological Institute in Sempach. Liechti and his colleagues attached 1.5-gram data loggers to three alpine swifts (Tachymarptis melba) at a Swiss breeding site, and recaptured the birds the following year. The loggers recorded the birds’ acceleration and geographic location. The measurements suggest that for 200 days, all three swifts remained airborne while migrating to and wintering in Africa. Liechti says researchers have previously asserted but never proved that newborn common swifts spend three years aloft before landing for breeding. “Amazing, truly amazing,” says Carsten Egevang of the Greenland Institute of Natural Resources in Nuuk of Liechti’s findings. “We knew that swifts stay on the wing for long periods, but 200 days is very impressive.”

The birds survive on airborne plankton, and almost certainly sleep on the wing too, Liechti says. “It has been assumed that the birds ‘sleep’ only for seconds, or use only one half of the brain while the other half is resting,” he says. But some researchers think the swifts might not sleep at all. “Our group has shown that dolphins and killer whales remain active for at least 90 days without sleep and with greatly reduced sleep for up to 150 days after birth,” says Jerry Siegel of the University of California at Los Angeles. He also cites recent work showing that sandpipers stay awake for weeks during breeding, and that dolphins can function without impaired performance for as long as 15 days without sleep. “What all this work tells us is that when it is adaptive for animals to remain awake, evolution allows that, so I think the idea that swifts must sleep and are therefore ‘sleep-flying’ is incorrect,” says Siegel. If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

New Scientist
October 29, 2013

Original web page at New Scientist

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Universal gown, glove use by employees in ICU reduces MRSA 40 percent

Healthcare workers’ use of disposable gowns and gloves upon entering all patient rooms on an intensive care unit (ICU), versus only in rooms on standard isolation protocol, helped reduce patient acquisition of methicillin-resistant Staphylococcus aureus (MRSA) by approximately 40 percent, according to new research co-led by the University of Maryland School of Medicine and the Yale New Haven Health System Center for Healthcare Solutions. While the study did not show statistically significant results for preventing patient acquisition of another common bacteria, vancomycin-resistant Enterococcus (VRE), the use of gowns and gloves increased handwashing frequency among healthcare workers and did not result in any increase in adverse events for patients. The study, funded by the Agency for Healthcare Research and Quality (AHRQ), appears online in JAMA in conjunction with presentation of the data at IDWeek, an annual meeting of more than 5,500 professionals in healthcare epidemiology and infectious diseases. Although recent data have indicated that healthcare-associated infections (HAIs) are becoming less pervasive across the United States, HAIs still represent one of the most common complications of hospital care, affecting an estimated one of every 20 patients. Numerous studies have shown that healthcare workers acquire bacteria on their hands and clothing through patient contact, resulting in transmission of bacteria to other patients. Current Centers for Disease Control and Prevention (CDC) guidelines recommend contact precautions (gowns and gloves) by healthcare workers when caring for patients colonized or infected with antibiotic-resistant bacteria such as MRSA and VRE. However, if these infections haven’t been detected, gowns and gloves do not have to be worn.

“We set out to find whether having healthcare workers wear gowns and gloves for all ICU patient contact could decrease the acquisition of antibiotic-resistant bacteria such as MRSA without causing any harm to the patient — and the answer was yes,” says the study’s principal investigator, Anthony D. Harris, M.D., MPH, professor of epidemiology and public health at the University of Maryland School of Medicine. Dr. Harris, who is also vice president of the Society for Healthcare Epidemiology of America (SHEA), adds: “From a public health perspective, it’s important that we evaluate interventions that may continue to drive these infection rates down, especially as concerns persist about antibiotic-resistant bacteria.” The study involved 20 medical and surgical ICUs across 15 states, and examined nearly 92,000 cultures from more than 26,000 patients over a nine-month period in 2012. Participating ICUs were randomly assigned to either the intervention or control group. Healthcare workers in the intervention group were required to wear gloves and gowns for all patient contact when entering any patient room. Healthcare workers in the control group followed CDC guidelines for patient contact, and only wore gloves and gowns for contact with patients with known antibiotic-resistant bacteria. While researchers did not find a decrease in VRE, the reduction in MRSA was notable, as was an increase in handwashing by the healthcare workers upon leaving patient rooms.

The study also sought to determine if usage of contact precautions such as gowns and gloves would adversely impact patients as previous studies have shown, such as increased instances of pressure sores, falls or other unintended physical injury resulting from medical care or hospitalization. However, there was no statistically significant increase in adverse events, and investigators observed a trend towards lower adverse events in the intervention group. “Infection control studies such as this are important to advance the science and lead to important discoveries that can decrease health care-associated infections,” says Daniel J. Morgan, M.D., M.S., the study’s senior author and assistant professor of epidemiology and public health at the University of Maryland School of Medicine. “In conjunction with the evolution of hospital cleaning practices, increased handwashing frequency and other measures, patients in hospitals can be safer than they’ve ever been from HAIs.” Beverly Belton, RN, MSN, a study co-author from Yale New Haven Health System Center for Healthcare Solutions, and PhD student at Yale University adds: “Based on the results of this study, it would be prudent for ICUs to consider adoption of universal gowning and gloving policies on intensive care units at highest risk for MRSA infections, regardless of whether patients have been positively cultured. Concerns about healthcare personnel acceptance of and compliance with universal gowning and gloving can be overcome with creative efforts focused on early engagement and positive reinforcement.”

Science Daily
October 29, 2013

Original web page at Science Daily

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Infanticide linked to wet-nursing in meerkats

Subordinate female meerkats who try to breed often lose their offspring to infanticide by the dominant female or are evicted from the group. These recently bereaved or ostracised mothers may then become wet-nurses for the dominant female, an activity that may be a form of “rent” that allows them to remain in the community. Wet-nursing another mother’s offspring — called allolactation — occurs across a variety of mammals and is thought to provide survival benefits to the nursed offspring and to the mother of the pups. However, little has been definitively known of why the females who provide the wet-nurse service do so. Now, in the most comprehensive study conducted to date, researchers studying a meerkat population in the Kalahari region of South Africa have identified factors that influence why females might wet-nurse. The findings, published today in Animal Behaviour, show that females are more likely to allolactate if they have recently lost litters or have returned to the group following eviction. “Breeding opportunities are monopolised by a single behaviourally dominant female in meerkat groups,” explains Kirsty MacLeod, who carried out the research at the University of Cambridge’s Department of Zoology with Professor Tim Clutton-Brock, and Johanna Nielsen at the University of Edinburgh. “She maintains this position through suppressing breeding attempts by other females — either through evicting them or killing their pups — and these subordinate females are then also more likely to wet-nurse the dominant female’s pups. This suggests to us that infanticide by the dominant female might have two evolutionary advantages for her — she reduces competition for care for her own pups, and is more likely to secure allolactation for her litter.

“Wet-nursing by formerly evicted meerkats may be a way of ‘paying rent’ to be allowed back into the group without receiving further aggression,” she adds. Helping as payment of ‘rent’ has been suggested in bird species in which helpers receive greater benefits from remaining in their territories owing to a lack of opportunity to attract a mate from elsewhere, but has previously been suggested in only one other mammal — the naked mole rat. The research was carried out over a 15-year period, with 40 social groups of meerkats being observed. The researchers created a long-term database and recorded, among other life-history details, pregnancies and lactation periods. Because most pup nursing occurs below ground, females were identified as producing milk through the presence of suckle marks and the attachment of sand to damp nipples. “Now that we have a clearer idea of which females are more likely to invest energy in this highly cooperative behaviour,” says MacLeod, “our next step is to figure out what benefits each party is getting from this. We know that lactation is costly, so it’s likely that if additional females also provide milk, those costs should go down. We’ll know that soon. “These results, however, hint at what the benefits might be for subordinate allolactators. Because subordinate females were more likely to allolactate if they are related to the litter’s mother, this suggests that they may gain an indirect benefit from the activity. Evictees from the group suffer considerable stress, weight loss and reduced survival. If contributing to the maternal cares of another’s offspring allowed renewed access to the social group, or to remain in the group once following infanticide, there would be an incentive to ‘pay-to-stay’.”

Science Daily
October 29, 2013

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Experiment explores innate visual behavior in mice

When you’re a tiny mouse in the wild, spotting aerial predators — like hawks and owls — is essential to your survival. But once you see an owl, how is this visual cue processed into a behavior that helps you to avoid an attack? Using an experimental video technique, researchers at the California Institute of Technology (Caltech) have now developed a simple new stimulus with which they can spur the mouse’s escape plans. This new stimulus allows the researchers to narrow down cell types in the retina that could aid in the detection of aerial predators. “The mouse has recently become a very popular model for the study of vision,” says biology graduate student Melis Yilmaz, who is also first author of the study, which will be published online in the journal Current Biology on October 10. “Our lab and other labs have done a lot of physiological, anatomical, and histological studies in the mouse retina” — a layer of light-sensitive cells in the eye that relay image information to the brain — “but the missing piece was mouse behavior: What do mice do with their vision?” Yilmaz, under the supervision of Markus Meister, Lawrence A. Hanson, Jr. Professor of Biology, studied the behavior of 40 mice, placed one-by-one in a tiny room called a behavioral arena. After placing each mouse alone in the arena and letting it explore the new environment for a few minutes, Yilmaz played videos of different visual stimuli on a computer monitor mounted on the ceiling, the screen facing down onto the arena. The researchers then watched a video feed of the mouse’s behavior, obtained with a camera located on one of the walls of the arena.

Surprisingly, all of the mice responded to one specific visual stimulus: an expanding black disk, which is meant to imitate the appearance of an approaching aerial predator. A quarter of the mice responded to the looming disk by completely freezing in place, not moving a muscle or twitching a whisker or tail until the disk disappeared. “When I first saw this behavior, my first thought was that the video recording had stopped,” Yilmaz says. A far more common reaction to the looming disk — seen in around 75 percent of the mice — was to flee for the cover of a tent-like nest in one corner of the arena. “For each mouse, this was the very first time that the animal was put into this arena, and it was the very first time that it saw that stimulus, and yet it has this sort of immediate reflex-like response…beginning to flee in less than a quarter of a second,” Meister says. “What’s attractive about this behavior is that it’s incredibly robust, so we can rely on it, and it’s quite specific to this particular visual stimulus. If the same disk was presented on a monitor at the bottom of the arena, the animals don’t respond to that at all. And a looming white disk is also much less effective,” he adds. Although their study wasn’t designed to evaluate the purpose of the two responses, Yilmaz and Meister suspect that, in the wild, different environmental conditions could lead to different visual behaviors.

“If you were out in nature, maybe freezing is a good reaction to a predatory bird that is very far away because it would allow you to blend into the surroundings,” Meister says. This would confound the bird’s visual system, which uses movement to track targets. Furthermore, he adds, “If the bird is within hearing distance, freezing so completely would help it avoid making a rustling noise.” The behaviors these researchers observed in this experiment are not uncommon among other animals in the wild, as Meister discovered one evening after giving a presentation about the fleeing and freezing results. “When I came home that evening, my son said, ‘Papi, you won’t believe what happened when we were at the park today. This squirrel was running across a wall, and suddenly it just froze! And then some guy yelled, ‘Hey look!’ and there was a hawk circling around.’ So he had just that day seen it in real life,” Meister says. Freezing might be the best game plan for an animal trying to avoid predators that are far away, but, Meister says, when the threat is closer “and there is a protective place nearby, then escape might be a better strategy.” When Yilmaz and Meister began connecting these specific behavioral observations with other information about the mouse visual system, they were able to make predictions about the types of neurons and circuits involved in this rapid response. “We tested four different speeds of the expanding disk video, and we found that only one of those speeds caused this behavior robustly,” Meister says. “That also gives us clues about what types of cells in the retina might be involved, because we know that one type responds to high-speed motion and one type responds to low-speed motions. The cells that detect low-speed motion are probably not involved in this behavior.”

“It’s really striking to me to watch the animal completely ignore one stimulus — like an expanding white disk — whereas they have such a robust reaction to the other type of stimulus,” Yilmaz says. Her next experiments will be focused on manipulating these candidate cell types to pinpoint exactly which types of neurons and circuits are involved in this visual behavior. In addition to its specific implications for visual behaviors, the work also helps to validate the mouse model for the study of visual processing, Meister says. Mice used in research have been bred for dozens of generations in laboratories — where they never would have seen an aerial predator — and yet the instinctual behavior still exists. “Lab mice never had to learn that a dark object from above was bad news,” he says. “In fact, in our experiments, there was never any kind of punishment or ill effect from a visual display, so they didn’t have any chance to learn the meaning. We believe it’s kind of built into their genetic constitution.” Although humans don’t have to escape the threat of predatory birds, Meister says that the results from this research could eventually provide information about human visual behaviors. “The mouse and human retinas are really very similar, so many of the circuits that are important for the mouse have analogous circuits in the human retina,” he says. “Humans also react instinctively to approaching objects, but, obviously, we don’t freeze. So, how did nature change a circuit that helps one animal escape from predators so that it serves a different function in another animal?”

Science Daily
October 29, 2013

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Tears for fears: Juvenile mice secrete a protective pheromone in their tears, blocking adult mating

Nocturnal animals need their noses to stay alive. Mice, among others, depend on their impressive olfactory powers to sniff out food or avoid danger in the dark. Hard-wired to flee a predator or fight a mating rival in response to a whiff of urine, mice use a streamlined system that sends the sensory cue to neural centers in the brain that need only a few synapses to rapidly initiate the instinctive behavior. By comparison, the visual system on which humans rely to sense a threat must process many more variables, detecting the edges and colors and contrast of that looming tiger they see, rather than sniffing the aroma of a cat — pungent only to animals — before scuttling away. In mice, social behaviors are also driven by these chemical signals, called pheromones. Scientists have observed differences in how mice interact with adult, juvenile or newborn mice, but they have not known which sensory cues allow mice to discriminate by age. While looking for novel pheromones that can control different instinctive mouse behaviors, researchers, led by Stephen Liberles, HMS associate professor of cell biology, have discovered a pheromone found only in the tears of young mice. Their experiments showed that this molecule, an exocrine-gland peptide named ESP22, protects prepubescent mice from mating activity by adult male mice. The research, reported October 2 in Nature, provides the first step toward a detailed understanding of how a sensory system can regulate social behavior.

“By identifying specific pheromones and the receptors they activate, you have a handle on the neural circuits that control these instinctive behaviors,” Liberles said. “The idea is to generate a toolbox of different pheromones that control different behaviors. Then you can dissect how the olfactory system selectively channels these inputs to enact appropriate behavioral responses.” The researchers examined the genomes of mice to identify genes that encode pheromones. They studied whether pheromone genes were turned on in male and female mice of different ages and physiological states. In adult mice, sex pheromones made by males influence sexual behavior in adult females and aggression in males, but less is known about pheromones in younger mice. The gene expression screen found Esp22 not in newborn mice but in the tears of juvenile mice. Juvenile pheromones had not been reported before, and much less attention has been focused on tears compared to urine, which is much easier to collect. To better understand the response pathway this molecule activated, the scientists traced it to sensory neurons in the vomeronasal organ (VNO), an olfactory structure that humans lack. Adult mice that have signaling deficits in this organ displayed increased sexual behavior toward the juvenile mice, the scientists observed. The scientists also saw adult mice exhibit the same behavior toward two strains of juvenile mice that don’t produce ESP22. But when ESP22 was painted onto these juvenile mice, there was a substantial reduction in sexual behavior by the adult males, suggesting that ESP22 is a protective pheromone.

Further tracking showed that ESP22 activates neurons in the limbic system, an area in the brain controlling instinctive drives: sexual behavior, aggression and self-defense. Much more remains in the dark, Liberles said. “We’d love to know what those neurons are, how they compare to other neurons in the limbic system, and how they might mediate responses to other types of pheromones and predator odors,” he said. “We would also like to find the receptor that detects this cue.” Mice are important models for understanding human behavior — the ultimate goal of this research program — but there are important differences. Humans don’t have a juvenile pheromone like ESP22. They don’t have an organ like the VNO. They also don’t recognize predator odors the way a mouse would. But humans do exhibit fear, aggression and sexual behavior. “Many of the behaviors are similar,” Liberles said. “We use the mouse as a model for understanding human behavior. This work provides a way to study mechanisms underlying behavior.”

Lisa Stowers, an associate professor of molecular and cellular neuroscience at the Scripps Research Institute in San Diego, called the study “convincing and complete.” While she leads a lab that investigates similar questions in the field, she was not involved in the research. “This is a very important molecule to study brain circuitry,” she said. “We don’t have the special olfactory system that mice have and we don’t have the odors that trigger behavior, but they trigger the same place in the brain, across evolution.” Stowers was cautious in drawing conclusions about mice in the wild versus mice in laboratory cages, much less leaping across species. What does a male mouse do when it is attracted to a female and smells a cat at the same time, for example? “By having these cues we can begin to find the neurons they activate and ask what happens in this balancing act between mating and fear,” she said. “We can ask how these behaviors are modulated and, in dysfunction, how they are not modulated.” ESP22 and other molecules Liberles has found provide powerful tools to understand how innate behaviors are produced in the brain, she said. “Thirty percent of humans take drugs to modulate stress and anxiety and aggression,” Stowers said. Despite how important these behaviors are, “we have no idea how they are produced in the brain by any animal — not worms, not flies, not mice and not humans. This is a first step, opening up whole new ways to study them.”

Science Daily
October 15, 2013

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Orangutans plan their future route and communicate it to others

Male orangutans plan their travel route up to one day in advance and communicate it to other members of their species. In order to attract females and repel male rivals, they call in the direction in which they are going to travel. Anthropologists at the University of Zurich have found that not only captive, but also wild-living orangutans make use of their planning ability. For a long time it was thought that only humans had the ability to anticipate future actions, whereas animals are caught in the here and now. But in recent years, clever experiments with great apes in zoos have shown that they do remember past events and can plan for their future needs. Anthropologists at the University of Zurich have now investigated whether wild apes also have this skill, following them for several years through the dense tropical swamplands of Sumatra. Orangutans generally journey through the forest alone, but they also maintain social relationships. Adult males sometimes emit loud ‘long calls’ to attract females and repel rivals. Their cheek pads act as a funnel for amplifying the sound in the same way as a megaphone. Females that only hear a faint call come closer in order not to lose contact. Non-dominant males on the other hand hurry in the opposite direction if they hear the call coming loud and clear in their direction.

“To optimize the effect of these calls, it thus would make sense for the male to call in the direction of his future whereabouts, if he already knew about them,” explains Carel van Schaik. “We then actually observed that the males traveled for several hours in approximately the same direction as they had called.” In extreme cases, long calls made around nesting time in the evening predicted the travel direction better than random until the evening of the next day. Carel van Schaik and his team conclude that orangutans plan their route up to a day ahead. In addition, the males often announced changes in travel direction with a new, better-fitting long call. The researchers also found that in the morning, the other orangutans reacted correctly to the long call of the previous evening, even if no new long call was emitted. “Our study makes it clear that wild orangutans do not simply live in the here and now, but can imagine a future and even announce their plans. In this sense, then, they have become a bit more like us,” concludes Carel van Schaik.

Science Daily
October 1, 2013

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Crop-raiding elephants flee tiger growls

Wild Asian elephants slink quietly away at the sound of a growling tiger, but trumpet and growl before retreating from leopard growls, researchers at the University of California, Davis, have found. The work, published Sept. 11 in the journal Biology Letters, could help Indian farmers protect their crops from marauding elephants and save the lives of both people and animals. “We noticed that the elephants were more scared of tigers than of leopards,” said Vivek Thuppil, who carried out the work with Richard Coss, professor of psychology at UC Davis, as part of his Ph.D. in animal behavior. Thuppil and Coss studied the elephants’ behavior in an effort to prevent conflicts between human farmers and elephant herds that raid their fields by night. It’s the first study of night time antipredator behavior in elephants. Crop raiding by elephants is a serious problem in India, Thuppil said. Farmers use drums, firecrackers and electrified fences to try to keep them out of their crops. About 400 people a year are killed during these encounters, and some hundred elephants are killed through poisoning, electrocution or other means, according to an Indian government report. The researchers set up equipment to play back leopard or tiger growls triggered when the elephants crossed infrared beams across paths leading to crop fields, and captured the events on video.

Leopards aren’t known to prey on elephants, but tigers will sometimes attack a young elephant that becomes separated from the herd. Although their initial reactions were very different, the elephants ultimately retreated from growls of both cats. The elephants might be confused by the leopard growl, Thuppil said. A real leopard would most likely retreat from a group of elephants. Still, there’s probably no benefit to the elephants in risking an encounter with a leopard, even if it is not a known predator. “You don’t want to mess with something with claws and teeth,” Thuppil said. “They’re acting in a very intelligent way,” Coss said. Wild elephant populations are stable or even increasing in forest areas, Thuppil said. While the forest itself is protected, human settlement increasingly has moved into the buffer areas surrounding the forest, which elephants pass through while foraging or visiting different patches of forest.

Science Daily
October 1, 2013

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Neuroscientists show that monkeys can decide to call out or keep silent

“Should I say something or not?” Human beings are not alone in pondering this dilemma — animals also face decisions when they communicate by voice. University of Tübingen neurobiologists Dr. Steffen Hage and Professor Andreas Nieder have now demonstrated that nerve cells in the brain signal the targeted initiation of calls — forming the basis of voluntary vocal expression. When we speak, we use the sounds we make for a specific purpose — we intentionally say what we think, or consciously withhold information. Animals, however, usually make sounds according to what they feel at that moment. Even our closest relations among the primates make sounds as a reflex based on their mood. Now, Tübingen neuroscientists have shown that rhesus monkeys are able to call (or be silent) on command. They can instrumentalize the sounds they make in a targeted way, an important behavioral ability which we also use to put language to a purpose. To find out how the neural cells in the brain catalyse the production of controled vocal noises, the researchers taught rhesus monkeys to call out quickly when a spot appeared on a computer screen. While the monkeys solved puzzles, measurements taken in their prefrontal cortex revealed astonishing reactions in the cells there. The nerve cells became active whenever the monkey saw the spot of light which was the instruction to call out. But if the monkey simply called out spontaneously, these nerve cells were not activated. The cells therefore did not signal for just any vocalisation — only for calls that the monkey actively decided to make.

The results published in Nature Communications provide valuable insights into the neurobiological foundations of vocalization. “We want to understand the physiological mechanisms in the brain which lead to the voluntary production of calls,” says Dr. Steffen Hage of the Institute for Neurobiology, “because it played a key role in the evolution of human ability to use speech.” The study offers important indicators of the function of part of the brain which in humans has developed into one of the central locations for controlling speech. “Disorders in this part of the human brain lead to severe speech disorders or even complete loss of speech in the patient,” Professor Andreas Nieder explains. The results — giving insights into how the production of sound is initiated — may help us better understand speech disorders.

Science Daily
September 17, 2013

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Primate calls, like human speech, can help infants form categories

Human infants’ responses to the vocalizations of non-human primates shed light on the developmental origin of a crucial link between human language and core cognitive capacities, a new study reports. Previous studies have shown that even in infants too young to speak, listening to human speech supports core cognitive processes, including the formation of object categories. Alissa Ferry, lead author and currently a postdoctoral fellow in the Language, Cognition and Development Lab at the Scuola Internationale Superiore di Studi Avanzati in Trieste, Italy, together with Northwestern University colleagues, documented that this link is initially broad enough to include the vocalizations of non-human primates. “We found that for 3- and 4-month-old infants, non-human primate vocalizations promoted object categorization, mirroring exactly the effects of human speech, but that by six months, non-human primate vocalizations no longer had this effect — the link to cognition had been tuned specifically to human language,” Ferry said. In humans, language is the primary conduit for conveying our thoughts. The new findings document that for young infants, listening to the vocalizations of humans and non-human primates supports the fundamental cognitive process of categorization. From this broad beginning, the infant mind identifies which signals are part of their language and begins to systematically link these signals to meaning.

Furthermore, the researchers found that infants’ response to non-human primate vocalizations at three and four months was not just due to the sounds’ acoustic complexity, as infants who heard backward human speech segments failed to form object categories at any age. Susan Hespos, co-author and associate professor of psychology at Northwestern said, “For me, the most stunning aspect of these findings is that an unfamiliar sound like a lemur call confers precisely the same effect as human language for 3- and 4-month-old infants. More broadly, this finding implies that the origins of the link between language and categorization cannot be derived from learning alone.” “These results reveal that the link between language and object categories, evident as early as three months, derives from a broader template that initially encompasses vocalizations of human and non-human primates and is rapidly tuned specifically to human vocalizations,” said Sandra Waxman, co-author and Louis W. Menk Professor of Psychology at Northwestern. “Is this link sufficiently broad to include vocalizations beyond those of our closest genealogical cousins,” asks Waxman, “or is it restricted to primates, whose vocalizations may be perceptually just close enough to our own to serve as early candidates for the platform on which human language is launched?”

Science Daily
September 17, 2013

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Australian cats and foxes may not deserve their bad rep

Foxes and feral cats are wildly unpopular among Australian conservationists. The two animals are infamous for killing off the continent’s native species, and they’ve been the targets of numerous government-backed eradication campaigns. But new research suggests that on Australian islands, these predators help control an even more destructive one: the black rat. As a result, eliminating cats and foxes could actually leave native mammals more vulnerable to predation, competition, and ultimately extinction. Australia is ground zero for the modern biodiversity crisis. The continent has suffered more than a quarter of all recent mammal extinctions, and many other native species survive only as small populations on one or more of the country’s thousands of islands. While habitat destruction has caused some extinctions, cats, foxes, and rats introduced around 1800 by British sailors have also played a major role, decimating native animals like bilbies and bandicoots—both small, ratlike marsupials found only in Australia. All of this has given large, nonnative predators like cats and foxes a bad name. “We hate them,” biologist Emily Hanna of the Australian National University in Canberra declared here last month at the International Congress for Conservation Biology.

But to plan successful eradication campaigns, scientists must first understand how introduced predators interact with native fauna and with each other. For instance, cats and foxes are infamous for hunting birds and other wildlife, but they can also control rats, which are themselves ferocious killers of and competitors with native animals like the bandicoot. To date, few studies have looked at which type of predator is actually most likely to drive native animals extinct. To determine which island invaders were doing the most damage, Hanna and her research adviser Marcel Cardillo created and analyzed what she calls a “ridiculously large” database comprising 934 living and extinct populations of 107 mammal species on 323 Australian islands between the early 1800s and today. For each island, the researchers recorded the presence or absence of various native mammals, and of rats, cats, foxes, and wild dogs known as dingoes, which some scientists believe help control invasive predators. The researchers also included other factors that might affect extinction risk, such as the size of the island and distance from the mainland. (Ecologists have found that island populations close to continents are more easily replenished, while more distant populations more easily go extinct.) Hanna then analyzed these data to find which factors most often correlated with native mammal extinctions.

The study yielded some surprising results: Native mammals were most likely to die off on islands that had rats, but not cats, foxes, or dingoes. Extinction rates on such islands ranged from 15% to 30%, but when cats, foxes, or dingoes were present, the rates plummeted to just over 10%—not much higher than on islands without any introduced predators, the scientists reported at the meeting and online this month in the journal Global Ecology and Biogeography. The scientists also found that native mammals fared only slightly worse on islands with cats than on islands without them. Moreover, the presence of foxes and dingoes on islands seemed to give native species a slight overall boost. “I was really surprised,” Hanna says. “I thought I’d made a big mistake.” Hanna and Cardillo also found that rats’ impact was most pronounced on small mammals—those weighing less than 2.7 kilograms—although the scientists are unsure how much of this influence was due to direct predation as opposed to competition for food and other resources or disease spread. Rats also had the greatest effect on islands within 2.1 kilometers of mainland Australia.

The study includes “a very nice, large data set, and a very well-constructed and complete analysis of the problem,” says Phillip Cassey, an ecologist at the University of Adelaide Environment Institute. The results suggest that managers may need to simultaneously eliminate more than one predator to save rare animals from extinction, he adds; eradication efforts frequently focus on only one species. When it comes to planning such eradication campaigns on limited budgets, Cassey says, “analyses like Hanna’s, which can assist in prioritization, are going to be really important.” Despite the apparent benefit of cats and foxes, Hanna does not advocate introducing the animals to islands that don’t already have them. But she says her results do raise questions about the strategy of trying to kill top predators off while ignoring rats. She now hopes to study whether her results also apply to birds and other groups of native species and to other predators.

ScienceNow
September 17, 2013

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Ostrich necks reveal Sauropod movements, food habits

A new analysis of ostriches reveals that a computer model of long-necked sauropods used to simulate the dinosaurs’ movements, featured in BBC’s Walking with Dinosaurs and the focus of an installation at the American Museum of Natural History, New York, does not correctly reconstruct how flexible their necks were. The results are published August 14 in the open access journal PLOS ONE by Matthew Cobley from the University of Utah, with colleagues from the University of Bristol and Natural History Museum, London. Previous estimates of sauropod neck flexibility were based on the positions of neck vertebrae, but this new research suggests these estimates were probably inaccurate, as the models don’t account for the effects of soft tissues like muscle and cartilage. This analysis of ostriches, close relatives of the long-necked sauropod dinosaurs, reveals that increasing muscle mass in the neck reduces the maximum flexibility of their necks. Variations in the distance between vertebral joints and the amount of cartilage present in the neck could also have reduced the flexibility of sauropods’ long necks, according to this research.

Museum exhibits and movies often depict sauropods arching their necks into a wide range of movements, all the way from tree-tops to low vegetation. However, the results of this study indicate that these dinosaurs may have been less flexible than typically depicted. Having less flexible necks would have likely restricted the range of foods these dinosaurs could reach, their ecological niches, and consequently, they may have foraged more actively to meet their average dietary needs of approximately 400 kg of plant matter each day. Cobley adds, “I believe the most important thing to take away from this study is that computer modeling of any biological system — be it anything from an individual organ to a whole dinosaur — needs to be ‘ground-truthed’ before it is accepted by the scientific community and presented to the public. It’s easy to be swayed by these beautifully reconstructed models of dinosaurs, but if these models aren’t based on real, empirical data taken from living animals we can actually study, they only serve to confuse the general public.”

Science Daily
September 3, 2013

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First documented report of swimming and diving in apes

Two researchers have provided the first video-based observation of swimming and diving apes. Instead of the usual dog-paddle stroke used by most terrestrial mammals, these animals use a kind of breaststroke. The swimming strokes peculiar to humans and apes might be the result of an earlier adaptation to an arboreal life. For many years, zoos have used water moats to confine chimpanzees, gorillas or orangutans. When apes ventured into deep water, they often drowned. Some argued that this indicated a definitive difference between humans and apes: people enjoy the water and are able to learn to swim, while apes prefer to stay on dry land. But it turns out that this distinction is not absolute. Renato Bender, who is working on a PhD in human evolution at the School of Anatomical Sciences at Wits University, and Nicole Bender, who works as an evolutionary physician and epidemiologist at the Institute of Social and Preventive Medicine at the University of Bern, have studied a chimpanzee and an orangutan in the US. These primates were raised and cared for by humans and have learned to swim and to dive. ‘We were extremely surprised when the chimp Cooper dived repeatedly into a swimming pool in Missouri and seemed to feel very comfortable,’ said Renato Bender.

To prevent the chimp from drowning, the researchers stretched two ropes over the deepest part of the pool. Cooper became immediately interested in the ropes and, after a few minutes, he started diving into the two-meter-deep water to pick up objects on the bottom of the pool. ‘It was very surprising behavior for an animal that is thought to be very afraid of water,’ said Renato Bender. Some weeks later, Cooper began to swim on the surface of the water. The orangutan Suryia, who was filmed in a private zoo in South Carolina, also possesses this rare swimming and diving ability. Suryia can swim freely up to twelve meters. Both animals use a leg movement similar to the human breaststroke ‘frog kick’. While Cooper moves the hind legs synchronous, Suryia moves them alternatively. The researchers believe that this swimming style might be due to an ancient adaptation to an arboreal life. Most mammals use the so-called dog-paddle, a mode of locomotion that they employ instinctively. Humans and apes, on the other hand, must learn to swim. The tree-dwelling ancestors of apes had less opportunity to move on the ground. They thus developed alternative strategies to cross small rivers, wading in an upright position or using natural bridges. They lost the instinct to swim. Humans, who are closely related to the apes, also do not swim instinctively. But unlike apes, humans are attracted to water and can learn to swim and to dive.

‘The behavior of the great apes in water has been largely neglected in anthropology. That’s one of the reasons why swimming in apes was never before scientifically described, although these animals have otherwise been studied very thoroughly. We did find other well-documented cases of swimming and diving apes, but Cooper and Suryia are the only ones we were able to film. We still do not know when the ancestors of humans began to swim and dive regularly,’ said Nicole Bender. ‘This issue is becoming more and more the focus of research. There is still much to explore,’ said Renato Bender.

Science Daily
September 3, 2013

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Dogs yawn more often in response to owners’ yawns than strangers

Dogs yawn contagiously when they see a person yawning, and respond more frequently to their owner’s yawns than to a stranger’s, according to research published August 7 in the open access journal PLOS ONE by Teresa Romero and colleagues from the University of Tokyo. Pet dogs in the study watched their owner or a stranger yawn, or mimic a yawning mouth movement, but yawned significantly more in response to their owners’ actions than to the strangers’ yawns. The dogs also responded less frequently to the fake movements, suggesting they have the ability to yawn contagiously. Previous research has shown that dogs yawn in response to human yawns, but it was unclear whether this was a mild stress response or an empathetic response. The results of this study suggest the latter, as dogs responded more to their owners’ genuine yawns than those of a stranger. The researchers observed no significant differences in the dogs’ heartbeat during the experiments, making it unlikely that their yawns were a distress response. Explaining the significance of the results, Romero says, “Our study suggests that contagious yawning in dogs is emotionally connected in a way similar to humans. Although our study cannot determine the exact underlying mechanism operative in dogs, the subjects’ physiological measures taken during the study allowed us to counter the alternative hypothesis of yawning as a distress response.

Science Daily
August 20, 2013

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Rubber slat mats could improve animal well-being

New research shows that rubber slat mats could improve swine health. In a new study in the Journal of Animal Science, researchers in Europe studied how different types of flooring affects claw and limb lesions, locomotion and flooring cleanliness. According to the researchers, flooring is one of the main factors in production systems that cause locomotory problems in swine. Locomotory problems can be caused by joint injuries or by circulatory problems in the legs and feet. Julia Calderón-Díaz, a PhD candidate at University of College Dublin, said pregnant sows placed on cushioned flooring would have a lower risk of being lame compared with sows placed on concrete. In this experiment, researchers studied the effects of two types of flooring on pregnant gilts in Ireland. One hundred sixty-four pregnant gilts were divided into two groups. One group was housed on concrete slatted floors, and the other group was housed on concrete slatted floors covered in rubber slat mats. The researchers scored locomotion and claw and limb lesion of the replacement gilts and flooring cleanliness periodically. The replacement gilts were observed from the time they were bred until 110 days into their pregnancy.

Dr. Alan Fahey, a lecturer at the University College Dublin said the gilts were studied during two pregnancies. The results were similar during both pregnancies. Sows housed on rubber mats had a reduced risk of swelling and wounds on the limbs. However, the rubber mats increased the risk of sole and heel lesions. Calderón-Díaz said these lesions were possibly caused by slurry accumulation over the rubber mats. She said these lesions were not severe and could be addressed through modifications of the rubber slat mats. In the European Union, pregnant sows must be group housed four weeks after breeding until one week before farrowing. This rule has been in effect since January. Calderón-Díaz said other countries are likely to use group housing for pregnant sows in the near future.

Science Daily
August 20, 2013

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Owlets spend more time in REM sleep than adult owls

Baby birds have sleep patterns similar to baby mammals, and their sleep changes in the same way when growing up. This is what a team from the Max Planck Institute for Ornithology and the University of Lausanne found out working with barn owls in the wild. The team also discovered that this change in sleep was strongly correlated with the expression of a gene involved in producing dark, melanic feather spots, a trait known to covary with behavioral and physiological traits in adult owls. These findings raise the intriguing possibility that sleep-related developmental processes in the brain contribute to the link between melanism and other traits observed in adult barn owls and other animals. Sleep in mammals and birds consists of two phases, REM sleep (“Rapid Eye Movement Sleep”) and non-REM sleep. We experience our most vivid dreams during REM sleep, a paradoxical state characterized by awake-like brain activity. Despite extensive research, REM sleep’s purpose remains a mystery. One of the most salient features of REM sleep is its preponderance early in life. A variety of mammals spend far more time in REM sleep during early life than when they are adults. For example, as newborns, half of our time asleep is spent in REM sleep, whereas last night REM sleep probably encompassed only 20-25% percent of your time snoozing.

Although birds are the only non-mammalian group known to clearly engage in REM sleep, it has been unclear whether sleep develops in the same manner in baby birds. Consequently, Niels Rattenborg of the MPIO, Alexandre Roulin of Unil, and their PhD student Madeleine Scriba, reexamined this question in a population of wild barn owls. They used an electroencephalogram (EEG) and movement data logger in conjunction with minimally invasive EEG sensors designed for use in humans, to record sleep in 66 owlets of varying age. During the recordings, the owlets remained in their nest box and were fed normally by their parents. After having their sleep patterns recorded for up to five days, the logger was removed. All of the owlets subsequently fledged and returned at normal rates to breed in the following year, indicating that there were no long-term adverse effects of eves-dropping on their sleeping brains. Despite lacking significant eye movements (a trait common to owls), the owlets spent large amounts of time in REM sleep. “During this sleep phase, the owlets’ EEG showed awake-like activity, their eyes remained closed, and their heads nodded slowly,” reports Madeleine Scriba from the University of Lausanne. Importantly, the researchers discovered that just as in baby humans, the time spent in REM sleep declined as the owlets aged.

In addition, the team examined the relationship between sleep and the expression of a gene in the feather follicles involved in producing dark, melanic feather spots. “As in several other avian and mammalian species, we have found that melanic spotting in owls covaries with a variety of behavioral and physiological traits, many of which also have links to sleep, such as immune system function and energy regulation,” notes Alexander Roulin from the University of Lausanne. Indeed, the team found that owlets expressing higher levels of the gene involved in melanism had less REM sleep than expected for their age, suggesting that their brains were developing faster than in owlets expressing lower levels of this gene. In line with this interpretation, the enzyme encoded by this gene also plays a role in producing hormones (thyroid and insulin) involved in brain development. Although additional research is needed to determine exactly how sleep, brain development, and pigmentation are interrelated, these findings nonetheless raise several intriguing questions. Does variation in sleep during brain development influence adult brain organization? If so, does this contribute to the link between behavioral and physiological traits and melanism observed in adult owls? Do sleep and pigmentation covary in adult owls, and if so how does this influence their behavior and physiology? Finally, Niels Rattenborg from the Max Planck Institute for Ornithology in Seewiesen hopes that “this naturally occurring variation in REM sleep during a period of brain development can be used to reveal exactly what REM sleep does for the developing brain in baby owls, as well as humans.”

Science Daily
August 20, 2013

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