The biology of fun and playfulness

Dog and child (stock image). Credit: © Irina84 / Fotolia

Current Biology celebrates its 25th birthday with a special issue on January 5, 2015 on the biology of fun (and the fun of biology). In a collection of essays and review articles, the journal presents what we know about playfulness in dogs, dolphins, frogs, and octopuses. It provides insights on whether birds can have fun and how experiences in infancy affect a person's unique sense of humor.

"Fun is obviously--almost by definition--pleasurable, rewarding, but in a way that is distinct from the pleasures of satisfying basic needs, such as the drives to reduce thirst or hunger or to reproduce," says Current Biology Editor Geoffrey North. "The articles in this special issue consider examples of what appear to be fun and play in a broad range of animal species and the insights that can be gained into how the behaviors might contribute to evolutionary fitness."

How do we get our sense of humor?

Psychologists Vasu Reddy and Gina Mireault, of the University of Portsmouth and Johnson State College respectively, offer a comprehensive overview of how, in infancy, reactions to absurd behavior like pulling hair or blowing raspberries, as well as teasing others, offer a window into how aware young children are of others' intentions. "As [infants] discover others' reactions and, indeed, others' minds, they also discover the meaning of 'funny', a construct that varies across and within cultures, regions, families, and even dyads," write the authors. "Infants become attuned to the nuances in humour through their social relationships, which create the practice of contexts of humorous exchange." The scientists note that children with atypical patterns of development may exhibit different senses of humor compared to their peers.

Why do adult apes play?

Based on her observations of a wild bonobo community, primatologist Isabel Behncke of the University of Oxford makes the case that play in bonobo adults could be a key adaptation that underlies social bonding and intelligence. She describes how bonobos in the Wamba community of Central Africa naturally engage in chasing, hanging, and water games despite differences in age and sex. "Play makes individuals more adaptable because it makes them more social; and more successful in their sociality as a result of being more adaptable," Dr. Behncke writes. "Life-long play is a bridge between sociality and adaptability."

Does playfulness spur creativity?

Ethologist Sir Patrick Bateson of the University of Cambridge wants to know why playfulness is so connected to creativity in the realms of science, music, and business. Working with behavioral biologist Daniel Nettle, he asked over 1,500 people to rank their creativity and then provide up to ten potential uses for a jam jar or paperclip. Those who considered themselves the most playful were most likely to provide many uses for the items. 

"Play is an effective mechanism for encouraging creativity since creativity also involves breaking away from established patterns of thought and behavior," Dr. Bateson writes.

Source: Cell Press

The bloody truth: How blood donations can save animals' lives

Donated blood can be quickly regenerated by the animal’s organism. Credit: Felizitas Steindl / Vetmeduni Vienna

Blood transfusions are of importance not only in human medicine. Also animals do need blood donations. The University of Veterinary Medicine, Vienna operates a blood bank for dogs for more than a decade. But also cats can donate blood for acute emergencies. Horses need blood donations especially during operations that involve high blood loss. Sheep, goats and other ruminants require transfusions when plagued by serious infestations of parasites. Three vets from different areas of expertise explain how blood transfusions work with different animal species and how they can save lives.

Blood can hardly be created through artificial means, but it can be transferred within a species. Reasons for a blood transfusion among dogs and cats are usually serious accidents, large operations, certain types of cancer, cases of intoxication with rat poison, serious infectious diseases such as the tick-borne babesiosis, and blood illnesses including haemolytic or inherited bleeding disorders such as haemophilia.

At the University of Veterinary Medicine, Vienna dog owners can bring their animals to donate blood regularly or as needed. Blood donations two to four times a year per dog is the maximum. About 15 minutes are required for a donation. Dogs must have a minimum weight of 25 kilograms and usually donate about 450 millilitres of blood. For cats, depending on their size, the amount taken is about 50 millilitres. Cats are typically sedated for the procedure. For most dogs, on the other hand, donating blood does not involve any serious stress. Should a donation cause too much anxiety or stress, the animal will be excluded as a donor.

Not all blood is alike

As with people, animals also have different blood types. Animal blood, as well as human blood, is divided into various groups based on different surface proteins found on the red blood cells. More than twelve different blood type systems have been described for dogs, although in practice dogs are only tested for DEA 1.1 positive or DEA 1.1 negative. Cats exhibit three different types of blood, horses eight and bovines eleven. The transfusion of an unsuitable blood type can have fatal consequences for animals, especially when a cat with blood type B receives type A blood. For horses and ruminants, the first time transfusion of 'wrong' donor blood is generally safe. With each additional transfusion, however, blood types become crucial, as the animals have produced antibodies against the foreign blood that can cause serious immune reactions.

Blood donations come with a health check

Dogs and cats can be registered as blood donors at the Clinical Unit of Internal Medicine Small Animals of the Vetmeduni Vienna. The animals receive a donor card and undergo a thorough examination before each donation. This mandatory health check includes a complete blood count, a test for blood parasites, and a check-up for viral infections.

"Donating blood does not harm the animals. The donated amount can be quickly regenerated by the animal's organism," says specialist for small animal internal medicine and blood bank coordinator Nicole Luckschander-Zeller. "We pay special attention to making sure that donor animals feel good during donation. That's why, after every donation, we give the animals a little snack."

Dog and cat blood is not only used as a whole. Individual blood components, such as plasma or erythrocyte concentrates, are stored and used when needed.

Horses as blood donors and recipients

There are various reasons for blood donations in equine medicine. These include clotting disorders of the blood, anaemia, poisonings or serious infectious diseases as well as perioperative blood loss. For the latter, blood is stored and kept ready for use during surgery in areas with strong blood supply, such as the nose and jaw. A blood transfusion helps to sustain adequate circulation of the animal during the operation and speeds recovery.

"The owners of diseased horses occasionally bring the suitable donor animal with them," says René van den Hoven, director of the Clinical Unit for Equine Internal Medicine at the Vetmeduni Vienna. The hospital also maintains a number of its own donor horses. The number of donations and the volume of the blood collected are registered in the horse's file, making it possible to plan future dates for donations without compromising the animal's health.

A maximum of five to seven litres of blood can be collected from a horse per donation. The blood must then be transfused into a patient within just a few hours. Storing whole equine blood is not a suitable option. As only plasma is desired for some treatments, the plasma is separated from the whole blood. Plasma is used for specific applications, for example to improve the healing of complicated wounds or during eye operations. Patients with massive protein loss can also be successfully treated with plasma. Protein loss may occur as a consequence of serious burn trauma, severe diarrhoea, tumours or chronic inflammatory intestinal disease, pleurisy or peritonitis.

Ruminants with anaemia need donated blood

Sheep, goats, lamas and alpacas are especially at risk of being infested by blood-sucking parasites out on the pasture. Ingested through the mouth, the worms come to inhabit the intestinal tract. A high level of parasitic infestation leads to serious cases of anaemia that may be fatal for the animals. "These acute patients require a rapid blood transfusion. Ruminants also receive blood for wounds with heavy blood loss, though this luckily is not often the case," explains the specialist for ruminant medicine, Lorenz Khol

Source:University of Veterinary Medicine -- Vienna

Fear and caring are what's at the core of divisive wolf debate

Fear and caring are what’s at the core of divisive wolf debate. Credit: Photo by G.L. Kohuth

To hunt or not hunt wolves can't be quantified as simply as men vs. women, hunters vs. anti-hunters, Democrats vs. Republicans or city vs. rural.

What's truly fueling the divisive debate is fear of wolves or the urge to care for canis lupis. The social dynamics at play and potential options for establishing common ground between sides can be found in the current issue of the journal PLOS ONE.

"People who are for or against this issue are often cast into traditional lots, such as gender, political party or where they live," said Meredith Gore, associate professor of fisheries and wildlife and co-lead author of the study. "This issue, however, isn't playing out like this. Concerns about hunting wolves to reduce conflict are split more by social geography and less by physical geography."

It's definitely an us-versus-them debate, she added. However, it took the concept of social identity theory to better reveal the true "us" and "them." Applying principles from social psychology revealed how the two groups were interacting and offers some potential solutions to get the vying groups to work together.

The team's findings are comparable, in part, to civil uprisings in the Middle East. The region is far removed from the United States, in terms of geography. Americans, however, tend to identify with a distant, threatened identity group, said Gore, an MSU AgBioResearch scientist.

"The concept of how our identity drives our activism is quite interesting," said Gore, who co-led the research with Michelle Lute, former MSU fisheries and wildlife graduate student who's now at Indiana University. "Our findings challenge traditional assumptions about regional differences and suggest a strong role for social identity in why people support or oppose wildlife management practices."

The majority of the nearly 670 surveys were collected from Michigan stakeholders interested in wolf-hunting as a management response to wolf conflicts. However, a small percentage of the data was gathered from participants in 21 states. While the study focused on gray wolves in Michigan, its results have implications for other states' policies on wolves as well as other large carnivores such as brown bears, polar bears, mountain lions and other predators, Gore added.

Noting that there's sharp polarization in debates about wolf management is not new. However, providing empirical evidence of its existence is new and meaningful because it provides a framework for improving engagement between the fighting factions.

For example, communications may be better directed toward each identity group's concerns of fear and care for wolves. These missives could be more effective than messages simply directed toward pro-hunters or anti-hunters. Identity-specific communications may also help build trust between agencies and stakeholders.

"These types of communications may not only build trust, but they can also contribute to a sense of procedural justice," Gore said. "This, in turn, may increase support for decision-makers and processes regardless of the outcome."

Also, by shaping and discussing the issue in terms of care and fear, rather than traditional qualifiers, may help usher in a greater agreement about management strategies.

Additional researchers working on this paper include Adam Bump, Michigan Department of Natural Resources.

Source: Michigan State University

Dogs hear our words and how we say them

The results from this study support the idea that our canine companions are paying attention "not only to who we are and how we say things, but also to what we say," authors say. Credit: © Uros Petrovic / Fotolia

 When people hear another person talking to them, they respond not only to what is being said--those consonants and vowels strung together into words and sentences--but also to other features of that speech--the emotional tone and the speaker's gender, for instance. Now, a report in the Cell Press journal Current Biology on November 26 provides some of the first evidence of how dogs also differentiate and process those various components of human speech.

"Although we cannot say how much or in what way dogs understand information in speech from our study, we can say that dogs react to both verbal and speaker-related information and that these components appear to be processed in different areas of the dog's brain," says Victoria Ratcliffe of the School of Psychology at the University of Sussex.

Previous studies showed that dogs have hemispheric biases--left brain versus right--when they process the vocalization sounds of other dogs. Ratcliffe and her supervisor David Reby say it was a logical next step to investigate whether dogs show similar biases in response to the information transmitted in human speech. They played speech from either side of the dog so that the sounds entered each of their ears at the same time and with the same amplitude.

"The input from each ear is mainly transmitted to the opposite hemisphere of the brain," Ratcliffe explains. "If one hemisphere is more specialized in processing certain information in the sound, then that information is perceived as coming from the opposite ear."
If the dog turned to its left, that showed that the information in the sound being played was heard more prominently by the left ear, suggesting that the right hemisphere is more specialized in processing that kind of information.

The researchers did observe general biases in dogs' responses to particular aspects of human speech. When presented with familiar spoken commands in which the meaningful components of words were made more obvious, dogs showed a left-hemisphere processing bias, as indicated by turning to the right. When the intonation or speaker-related vocal cues were exaggerated instead, dogs showed a significant right-hemisphere bias.

"This is particularly interesting because our results suggest that the processing of speech components in the dog's brain is divided between the two hemispheres in a way that is actually very similar to the way it is separated in the human brain," Reby says.
Of course, it doesn't mean that dogs actually understand everything that we humans might say or that they have a human-like ability of language--far from it. But, says Ratcliffe, these results support the idea that our canine companions are paying attention "not only to who we are and how we say things, but also to what we say."

All of this should come as good news to many of us dog-loving humans, as we spend considerable time talking to our respective pups already. They might not always understand you, but they really are listening.

Source: Cell Press

People ate mammoth; Dogs got reindeer

Artist's depiction of cave painting of primitive hunt

Biogeologists have shown how Gravettian people shared their food 30,000 years ago.

Předmostí I is an exceptional prehistoric site located near Brno in the Czech Republic. Around 30,000 years ago it was inhabited by people of the pan-European Gravettian culture, who used the bones of more than 1000 mammoths to build their settlement and to ivory sculptures. Did prehistoric people collect this precious raw material from carcasses -- easy to spot on the big cold steppe -- or were they the direct result of hunting for food? This year-round settlement also yielded a large number of canids remains, some of them with characteristics of Palaeolithic dogs. Were these animals used to help hunt mammoths?

To answer these two questions, Tübingen researcher Hervé Bocherens and his international team carried out an analysis of carbon and nitrogen stable isotopes in human and animal fossil bones from the site. Working with researchers from Brno and Brussels, the researchers were able to test whether the Gravettian people of Předmostí ate mammoth meat and how the "palaeolithic dogs" fit into this subsistence picture.

They found that humans did consume mammoth -- and in large quantities. Other carnivores, such as brown bears, wolves and wolverines, also had access to mammoth meat, indicating the high availability of fresh mammoth carcasses, most likely left behind by human hunters. Surprisingly, the dogs did not show a high level of mammoth consumption, but rather consumed essentially reindeer meat that was not the staple food of their owners. A similar situation is observed in traditional populations from northern regions, who often feed their dogs with the food that they do not like. These results also suggest that these early dogs were restrained, and were probably used as transportation helpers.

These new results provide clear evidence that mammoth was a key component of prehistoric life in Europe 30,000 years ago, and that dogs were already there to help.

Source: Universitaet Tübingen

Attitudes about knowledge, power drive Michigan's wolf debate

MSU research has identified the themes shaping Michigan's wolf debate and offers some potential solutions as the debate moves forward. Credit: Courtesy of Michigan DNR

With both wolf proposals shot down by Michigan voters on election day, the debate over managing and hunting wolves is far from over.

A Michigan State University study, appearing in a recent issue of the Journal of Wildlife Management, identifies the themes shaping the issue and offers some potential solutions as the debate moves forward.

The research explored how different sides of the debate view power imbalances among different groups and the role that scientific knowledge plays in making decisions about hunting wolves. These two dimensions of wildlife management can result in conflict and stagnate wildlife management.

The results indicate that tension between public attitudes about local knowledge, and politics and science can drive conflict among Michiganders' stance regarding wolf hunting, said Meredith Gore, associate professor of fisheries and wildlife and co-lead author of the study.

"Given the trend in wildlife management toward increased stakeholder input, finding solutions that approach science and politics as complementary, rather than competing, approaches may aid the public participation processes," she said.

This study represents a first attempt at defining and describing the association between knowledge and power in contentious management of a species recently delisted from endangered status. This study focused on wolves, but it has applications for other endangered or invasive species, added Gore, an MSU AgBioResearch scientist.

These findings shed light on why the voting and support for the issue appears to be muddled, at least in terms of traditional quantifiers. Knowing these splits explain, in part, why the issue won't likely be resolved by swaying the pro- or anti-hunting vote.

Gore and Michelle Lute, former MSU fisheries and wildlife graduate student and co-lead author who's now at Indiana University, unearthed these disparities by conducting in-depth interviews with many stakeholders close to the wolf debate. Rather than trying to prove a specific theory, the researchers allowed the interviews to reveal the main criteria driving the issue.

The researchers unearthed four themes and offered potential solutions to each.

• Mistrust among decision-makers -- Some interviewees view wildlife management agencies as political agencies rather than supporting what's best for wildlife. Increasing transparency and gathering more stakeholder input could increase trust.
• Special interest groups leaving many voters disenfranchised -- Strong lobbying groups leave some individuals feeling powerless and their votes meaningless. Striving for equitable distribution of risks and benefits among all stakeholders could address these feelings.
• Political influencers overriding science -- Some believe that scientific studies are downplayed by political officials. Equitable sharing of responsibility, risks and benefits may ease perceptions of tension between politicians and scientists.
• Decision-makers ignoring local sources of information -- Some interviewees felt cast aside, and their knowledge was labeled as mythology or folklore. Processes that seek shared-learning outcomes may balance local and scientific knowledge.

"Our research shows that as any management process moves forward," Gore said, "all sides should address the issue from the perspective of these four criteria. Regardless of how people voted, these aspects may represent common ground for all sides."

Source: Michigan State University

Odor that smells like blood: Single component powerful trigger for large carnivores

African wild dogs compete for a log impregnated with blood or a single component. Both were equally attractive. Credit: Linköping University

People find the smell of blood unpleasant, but for predatory animals it means food. When behavioural researchers at Linköping University in Sweden wanted to find out which substances of blood trigger behavioural reactions, they got some unexpected results.

Matthias Laska is professor of zoology, specialising in the sense of smell. For some time his focus has been on scents that directly affect the behaviour of animals.

"For predators, food scents are particularly attractive, and much of this has to do with blood. We wanted to find out which chemical components create the scent of blood," he says.

The study, conducted at Kolmården Wildlife Park, found that for the animals, one particular component of blood odour was just as engaging as the blood odour itself.

"It's a completely new discovery that raises interesting questions on evolution," says Prof Laska.

The study has been published in the scientific journal PLOS ONE.

When Prof Laska did a search for the contents of volatile substances in mammalian blood, he found nothing. Human blood has been analysed for disease markers, but we have very little information on the substances that give blood its characteristic scent.

A master's student was sent to Friedrich-Alexander-Universität in Erlangen Germany, to analyse mammalian blood with the help of gas chromatography and mass spectrometry, methods used for separating and identifying chemical compounds in a sample. The machine detected some 30 substances, of which some are decomposition products from fats. But the machine lost the job to the human scent experts who had also been engaged. They identified scents that the gas chromatograph missed completely.

One substance stood out: an aldehyde called trans-4,5-epoxy-(E)-2-decenal, which emits the typical metallic scent that humans associate with blood.

Once the researchers had identified a scent candidate that the predators should be attracted to, they wanted to test whether the predators were actually attracted to it in reality. So they designed a study to be conducted at Kolmården Wildlife Park, involving four predator species. How would the four predators -- Asian wild dogs, African wild dogs, South American bush dogs and Siberian tigers -- react when they caught a whiff of the scent?

Half-metre long wooden logs were impregnated with four different liquids: lab-produced aldehyde, horse blood, fruit essence, and a near-odourless solvent. The animals were exposed to one scent per day in their regular enclosure, while a group of students carefully observed their behaviour.

The results were unequivocal. The logs containing aldehyde were just as attractive stimuli as those containing blood, while the two other logs aroused little interest. The commonest behaviours were sniffing, licking, biting, pawing and toying. The tiger was the most persistent, while the South American bush dogs lost interest more quickly than the other species.

The study is the first to show that a single component can be just as attractive as the complex odour.

"How this has developed through evolution is an interesting question. Perhaps there is a common denominator for all mammalian blood," says Prof Laska.

He has plans for several follow-ups of the study, including how prey animals such as mice react to blood odour.

For the wildlife park, the study provided results that can be used in its daily operations. Animals in captivity require stimulation, so as not to deteriorate or become fat. The odourised logs can be a popular addition to the animal's environment.

Source: Linköping University

New natural supplement relieves canine arthritis

Portrait old dog

Arthritis pain in dogs can be relieved, with no side effects, by a new product based on medicinal plants and dietary supplements that was developed at the University of Montreal's Faculty of Veterinary Medicine. "While acupuncture and electrical stimulation are two approaches that have been shown to have positive effects on dogs, until now a few studies have investigated a plant-based approach to therapy," explained Professor Éric Troncy, senior author of the study. His findings were published in Research in Veterinary Science.

Troncy and his team worked with 32 dogs (and their owners!) who had been diagnosed with arthritis by X-ray and orthopaedic exam, and who all weighed more than 20 kilograms. By drawing on existing rodent studies and working with Pierre Haddad of the university's Department of Pharmacology, Troncy developed two formulas for his trial. These formulas are not currently commercially available.

The first formula, composed of curcumin, devil's claw, black current, Indian frankincense (Salai), willow bark, pineapple bromelaine and camomile, was developed to treat arthritis-induced inflammation. The second included the same ingredients, plus dietary supplements such as omega 3, chondroitin sulfate and glutamine, and was formulated in the hope that it would promote the regeneration of articulations.

Half the dogs received the first formula for four weeks and then the second formula for another four weeks. The other half, acting as the control, received a placebo. The outcomes were tested using three methods. Firstly, the dogs were filmed as they walked at a consistent speed over a special platform that captures the strength of each paw. Secondly, a special electronic collar recorded the dogs' daily activities. And finally, the owners were asked to provide their own evaluations of their dog's behaviour.

The researchers were able to identify an improvement by the fourth week of the trial. "After the eight week course, on average, the strength of the dogs receiving treatment had improved to the equivalent of a kilo of extra strength per paw, which is moreover. None of these dogs saw their health decline, unlike 35.8% of the dogs who were given the placebo," said Maxim Moreau, who was first author of the study.

The improvements were also reflected in the dogs' daily lives. The collars revealed that the dogs receiving treatment maintained their physical activity, and in fact the group average increased from six hours of daily activity to eight. Meanwhile, the dogs receiving the placebo were progressively less active. "In some cases, we recorded the dogs to ensure that the collar was recording actual physical activity rather than movements such as scratching," Troncy explained.

Nonetheless, the ratings from the owners were more mixed. "This third evaluation was more subjective and the contrast between the test group and the control group less stark," Troncy said. "We suspect that the owner may have forgotten what the animal's behaviour was like before it developed arthritis."

The findings raise the possibility of offering a new form of treatment to human beings. "The model of evaluation that we have used is the best for predicting the efficacy of anti-arthritis treatments. We can therefore consider that clinical trials on humans would have a good chance of having positive outcomes," Troncy said.

About this study: This study was funded in part by a grant from ArthroLab Inc., an ongoing New Opportunities Fund grant (#9483) and a Leader Opportunity Fund grant (#24601) from the Canada Foundation for Innovation for the pain/function equipment, a Discovery Grant (#327158-2008; #441651-2013) from the Natural Sciences and Engineering Research Council of Canada for the bio-analyses and salaries, and by the Osteoarthritis Chair of the University of Montreal Hospital Centre, Université de Montréal. Maxim Moreau received a doctoral scholarship from the Canadian Institutes of Health Research (TGF-53914) -- Strategic Training Initiative in Health Research program (MENTOR) and a doctoral scholarship from the Fonds de recherche du Québec-Santé.

Source: Universite de Montreal

For tiger populations, a new threat

This is an Amur tiger photographed by camera trap. Credit: WCS Russia Program

Along with the pressures of habitat loss, poaching and depletion of prey species, a new threat to tiger populations in the wild has surfaced in the form of disease, specifically, canine distemper virus (CDV). According to a new study from the Wildlife Conservation Society (WCS) and its partners, CDV has the potential to be a significant driver in pushing the animals toward extinction.

While CDV has recently been shown to lead to the deaths of individual tigers, its long-term impacts on tiger populations had never before been studied.

The authors evaluated these impacts on the Amur tiger population in Russia's Sikhote-Alin Biosphere Zapovednik (SABZ), where tiger numbers declined from 38 individuals to 9 in the years 2007 to 2012. In 2009 and 2010, six adult tigers died or disappeared from the reserve, and CDV was confirmed in two dead tigers -- leading scientists to believe that CDV likely played a role in the overall decline of the population. Joint investigations of CDV have been an ongoing focus of WCS and Russian scientists at Sikhote-Alin Zapovednik and veterinarians at the regional Primorye Agricultural College since its first appearance in tigers in 2003.

A key finding of this study: Modeling shows that smaller populations of tigers were found to be more vulnerable to extinction by CDV. Populations consisting of 25 individuals were 1.65 times more likely to decline in the next 50 years when CDV was present. The results are profoundly disturbing for global wild tigers given that in most sites where wild tigers persist they are limited to populations of less than 25 adult breeding individuals.

The scientists used computer modeling to simulate the effects of CDV infection on isolated tiger populations of various sizes and through a series of transmission scenarios. These included tiger-to-tiger transmission and transmission through predation on CDV-infected domestic dogs and/or infected wild carnivores (such as foxes, raccoon dogs and badgers). High and low-risk scenarios for the model were created based on variation in the prevalence of CDV and the tigers' contact with sources of exposure.

Results showed that CDV infection increased the 50-year extinction probability of tigers in SABZ as much as 55.8 percent compared to CDV-free populations of equivalent size.

"Although we knew that individual tigers had died from CDV in the wild, we wanted to understand the risk the virus presents to whole populations," said WCS veterinarian Martin Gilbert. "Tigers are elusive, however, and studying the long-term impact of risk factors is very challenging. Our model, based on tiger ecology data collected over 20 years in SABZ, explored the different ways that tigers might be exposed to the virus and how these impact the extinction risk to tiger populations over the long term."

WCS Russia Program Director Dale Miquelle said, "Tigers face an array of threats throughout their range, from poaching to competition with humans for space and for food. 

Consequently, many tiger populations have become smaller and more fragmented, making them much more susceptible to diseases such as CDV. While we must continue to focus on the primary threats of poaching and habitat destruction, we now must also be prepared to deal with the appearance of such diseases in the future."

Priorities for future research, according to the authors, include identifying the domestic and wild carnivore species that contribute to the CDV reservoir, and those that are the most likely sources of infection for tigers. Tigers are too rare to sustain the virus in the long term, so CDV must rely on more abundant carnivore species to persist in the environment. 

Understanding the structure of the CDV reservoir will be a critical first step in identifying measures that might prevent or control future outbreaks. In addition, since we now know that small tiger populations are at greater risk to diseases such as CDV than larger populations, conservation strategies focusing on connectedness between populations become all the more important. "Estimating the potential impact of canine distemper virus on the Amur tiger population (Panthera tigris altaica) in Russia," appears in the current online edition of PloSONE. Authors include: Martin Gilbert of WCS and Boyd Orr Centre for Population and Ecosystem Health at the University of Glasgow; Dale G. Miquelle of WCS; John M. Goodrich of Panthera; Richard Reeve, Sarah Cleaveland and Louise Matthews of Boyd Orr Centre for Population and Ecosystem Health at the University of Glasgow; and Damien Joly of WCS and Metabiota.

This study was made possible through generous support from Morris Animal Foundation, Zoo Boise Conservation Fund, AZA Tiger Species Survival Plan Tiger Conservation Campaign, and the Biotechnology and Biological Sciences Research Council.

"Morris Animal Foundation is thankful to Dr. Miquelle and his team for helping protect the Amur Tigers," said Diane Brown, DVM, PhD, DACVP and Chief Scientific Officer for Morris Animal Foundation. "Our Foundation values their hard work and dedication to this study and we look forward to many more partnerships with the Wildlife Conservation Society."

Source: Wildlife Conservation Society

Cat genome reveals clues to domestication​​

Cats and humans have shared the same households for at least 9,000 years, but we still know very little about how our feline friends became domesticated.

Cats and humans have shared the same households for at least 9,000 years, but we still know very little about how our feline friends became domesticated. An analysis of the cat genome led by researchers at Washington University School of Medicine in St. Louis reveals some surprising clues.

The research appears Nov. 10 in the Proceedings of the National Academy of Sciences Early Edition.

Cats have a relatively recent history of domestication compared with dogs; canines arose from wolves over 30,000 years ago.

"Cats, unlike dogs, are really only semidomesticated," said senior author Wes Warren, PhD, associate professor of genetics at The Genome Institute at Washington University​. "They only recently split off from wild cats, and some even still breed with their wild relatives. So we were surprised to find DNA evidence of their domestication."

One way scientists can understand the genetics of domestication is to look at what parts of the genome are altered in response to living together with humans, Warren added.
The researchers compared the genomes of domestic cats and wild cats, finding specific regions of the domestic cat genome that differed significantly.

The scientists found changes in the domestic cat's genes that other studies have shown are involved in behaviors such as memory, fear and reward-seeking. These types of behaviors -- particularly those when an animal seeks a reward -- generally are thought to be important in the domestication process.

"Humans most likely welcomed cats because they controlled rodents that consumed their grain harvests," said Warren. "We hypothesized that humans would offer cats food as a reward to stick around."

This meant that certain cats that would normally prefer to lead solitary lives in the wild had an additional incentive to stay with humans. Over time, humans preferred to keep cats that were more docile.

Cat genome project

The cat genome sequencing project, funded by the National Human Genome Research Institute, part of the National Institutes of Health (NIH), began in 2007. The project's initial goal was to study hereditary diseases in domestic cats, which are similar in some cases to those that afflict humans, including neurological disorders, and infectious and metabolic diseases.

To obtain the high-quality reference genome needed for this research, the team sequenced a domestic female Abyssinian cat named Cinnamon. They chose this particular cat because they could trace its lineage back several generations. This cat's family also had a particular degenerative eye disorder the researchers wanted to study.

To better understand characteristics of domestication, the researchers sequenced the genomes of select purebred domestic cats. Hallmarks of their domestication include features such as hair color, texture and patterns, as well as facial structure and how docile a cat is. Cats are bred for many of these types of characteristics. In fact, most modern breeds are the result of humans breeding cats for their favorite hair patterns.

The team also looked at a breed called Birman, which has characteristic white paws. The researchers traced the white pattern to just two small changes in a gene associated with hair color. They found that this genetic signature appears in all Birmans, likely showing that humans selectively bred these cats for their white paws and that the change to their genome happened in a remarkably short period of time.

The group also compared the cat genome with those of other mammals -- including a tiger, cow, dog and human -- to understand more about the genetics of cat biology.

"We looked at the underlying genetics to understand why certain abilities to survive in the wild evolved in cats and other carnivores," said Michael Montague, PhD, the study's first author and a postdoctoral research associate at The Genome Institute.

The differences they found in the cat genome help explain characteristics such as why cats are almost exclusively carnivorous and how their vision and sense of smell differ from other animals like dogs.

Solitary carnivores

To digest their fatty, meat-heavy meals, cats need genes to efficiently break down fats. The team found particular fat-metabolizing genes in carnivores such as cats and tigers that changed faster than can be explained by chance. This more rapid change generally means these genes provide some sort of digestive advantage to carnivores that only consume animal proteins. The researchers did not find such changes in the same genes of the cow and human, who eat more varied diets and would not need such enhancements.

Cats also rely less on smell to hunt than dogs. So it is not surprising that the researchers found fewer genes for smell in cats than dogs. But they did find more genes related to an alternate form of smell that detects chemicals called pheromones, which allow cats to monitor their social environment, including seeking out the opposite sex. This ability is not as important to dogs, which tend to travel in packs. But it is crucial in cats, which are more solitary and may have more difficulty finding mates.

Cats also have better hearing than most other carnivores, including an ability to hear in the ultrasonic range to better track prey. Their vision is also exceptional in low light.

"Cats tend to be more active at dawn and dusk," said Montague, "so they need to be able to detect movement in low light." Accordingly, the team identified specific genes that likely evolved to expand cats' hearing range and their vision in low light.

Even though the genomes of domestic cats have changed little since their split from wild cats, the new work shows that it is still possible to see evidence of the species' more recent domestication. "Using advanced genome sequencing technology, we were able to shed light on the genetic signatures of cats' unique biology and survival skills," said Warren. "And we were able to significantly jump start our knowledge about the evolution of cat domestication."

Collaborators in the research include Texas A&M University; University of Missouri-Columbia; University of California-Davis; Wellcome Trust Sanger Institute in the United Kingdom; Pompeu Fabra University in Spain; Centro de Analisis Genomico in Spain; Bilkent University in Turkey; Indiana Univeristy; Center for Cancer Research in Maryland; St. Petersburg State University in Russia; and Nova Southeastern University in Florida.

Source: Washington University in St. Louis

Boy moms more social in chimpanzees: Watching adult males in action may help youngsters prepare

Infant chimpanzee in Gombe National Park, Tanzania. Nearly four decades of observations of Tanzanian chimpanzees has revealed that the mothers of sons are about 25 percent more social than the mothers of daughters. Boy moms were found to spend about two hours more per day with other chimpanzees than the girl moms did. Credit: © Impala / Fotolia

Nearly four decades of observations of Tanzanian chimpanzees has revealed that the mothers of sons are about 25 percent more social than the mothers of daughters. Boy moms were found to spend about two hours more per day with other chimpanzees than the girl moms did.

Chimpanzees have a male-dominated society in which rank is a constant struggle and females with infants might face physical violence and even infanticide. It would be safer in general to just avoid groups where aggressive males are present, yet the mothers of sons choose to do so anyway.

"It is really intriguing that the sex of her infant influences the mother's behavior right from birth and that the same female is more social when she has a son than when she has a daughter," said Anne Pusey, chair of Evolutionary Anthropology at Duke.

The researchers believe that the mothers are giving the young males the opportunity to observe males in social situations, even while still clinging to their mothers. This gives the youngsters a start on developing the social skills they'll need to thrive in the competitive world of adults.

The findings are based on an analysis of 37 years of daily observations of East African chimpanzeess from the Gombe National Park in Tanzania. Duke University houses all of the data from the famous Kasekela chimpanzee community in the Jane Goodall Institute Research Center, which contains more than 50 years of observational data all the way back to Jane Goodall's first hand-written observations from the early 1960s.

The data largely consist of "follows," in which a researcher focuses on one chimpanzee and notes her behaviors and interactions with others throughout the day. Duke scholars led by Pusey are now working on digitizing the entire collection of Gombe data in the Goodall archive to enable more longitudinal studies of this kind.

"Drawing from the long-term datasets, we were able to investigate patterns within the same mother, examining how she behaved with her sons versus with her daughters," said lead author Carson Murray, an assistant professor at George Washington University, who was a PhD student under Pusey. "These results are even more compelling than a general pattern, demonstrating that the same female behaves very differently depending on the sex of her offspring."

For this study, researchers measured gregariousness based on three kinds of analyses. They looked at how much time a mother spent with other adults who were not immediate family members; the average size of the mother's party and its composition; and the proportion of time a mother spent in mixed-sex and female-only parties.

For the most part, mothers with offspring spend their time alone or with adult daughters and other dependents. Adult males are the more gregarious sex, forming coalitions with other males to assert rank, defend their territory and hunt as a group.

Mothers with sons were found to spend more time with others and to associate with more of their kin. During the first six months of an infant's life, mothers with sons spend significantly more time in mixed-sex parties than mothers with daughters.

At 30 to 36 months, chimpanzee infants start moving around more on their own without being carried and spend most of their time out of mother's reach. At this age, the male infants start having more interactions with unrelated chimpanzees, especially adult males. Their female counterparts are significantly less social.

As the offspring get older and range further from their mothers, the young males have more social partners over the course of the day. Juvenile and adolescent males watch their adult counterparts carefully and often mimic the behaviors they see, including charging displays and copulation.

"Mothers obviously increase social exposure for their young male infants," Murray said. "This finding leads to a larger question about how social exposure might shape gender-typical behavior in humans as well."

This study also suggests it is possible the sons themselves are driving the increased gregariousness later in life. In early infancy, the boy mothers spend about the same time in female-only groups that the girl moms do. But as their sons become older, boy moms spend more time in female-only, nursery groups, probably because the young males are attracted to the offspring of other females as playmates.

"One of the most surprising results to me was that mothers with young females still have lower association with their relatives," Murray said. "As we argue in the paper, this suggests that social exposure is less critical to females in general."

Social exposure has a potential downside too. Females with low rank are known to experience more social stress in large groups, and there is always a risk of infanticide against the young chimpanzees. Perhaps the best way to avoid having infants killed is to steer clear of groups, which the mothers do up to 70 percent of the time.

"Mothers with infant daughters were likely to be avoiding competitive and stressful situations," Murray said. "While mothers with sons seem willing to incur those costs for the benefit of having their sons socialized."

Source: Duke University.