A new project is aiming to predict the potential spread of the world’s only prion disease found in wild animals. The research aims to second-guess the effects of chronic wasting disease (CWD), a fatal condition similar to mad cow disease that affects several species of deer. Given the conservation implications of the deadly disease for the deer, and the uncertainty over whether it can be spread to humans, it’s a timely research effort.

CWD is endemic in parts of the United States such as the mid-northwest, but is a newcomer to upstate New York. (It was first spotted in April 2005 when a deerhunter provided a fawn for a firemen’s dinner; subsequent tests showed that it was infected with deformed prion protein but by then the diners had already eaten it. Whether they will develop mad cow-like symptoms in the coming decades remains to be seen.)

Amy Dechen of the State University of New York in Syracuse has been fitting healthy deer with GPS collars in the New York woodlands in a bid to find out where they roam and how these patterns of movement might influence the spread of the contagion by infected individuals. The capture and tagging of infected deer is not allowed. Although Dechen only has preliminary results, the information on range size and roaming patterns of the deer could prove valuable in calculating where and when the disease might spring up in other wild deer. As for whether it can be transmitted to humans, the jury is still out. The WHO states in its factsheet on transmissible spongiform encephalopathies that no material from infected deer or elk be used in human or animal food, but adds that there is so far no evidence that the disease can be spread to humans.

One of the most thought-provoking discussions at the meeting has been on the welfare of captive non-human primates. We share an undeniably close kinship with these animals, particularly in the case of chimps, but interpreting their behaviour and trying to act in their best interests seems as thorny as ever. Some experts argue that, if we give them the chance, the chimps will tell us exacty what they want. But the problem is that in learning to communicate with us, the chimps must necessarily adopt a more human lifestyle than they would otherwise have.

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How’s this for an interesting theory – the dietary switch that paved the way for the evolution of our impressive intelligence also made us more prone to illness.

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Rats can smell whether two people are related or not, according to new research. The discovery underlines the fact that a person’s natural smell can depend on their genes, and that odour similarities between related people are significant enough to be detected by the sensitive nose of a rat.

Erin Ables of Indiana University carried out the slightly bizarre experiment by recruiting groups of women, including pairs of relatives, and asking them to shower in non-scented soap, as well as avoiding smelly foods or cosmetics. She then presented smells to the rats – first from one woman and then another, either related or unrelated to the first. Rats spent longer sniffing the odours from unrelated women, and as rats spend longer investigating novel odours, this suggests that related women bear similar natural smells. The rats were even sensitive enough to spot the difference between a mother-daughter relationship and the more distant aunt-niece link.

It’s unclear whether people can consciously detect such differences, but it seems likely that we might appreciate them on some level. A person’s natural smell gives subtle clues about the genetics of their immune system, and people naturally tend to prefer the smells of people with different, and therefore complementary, immune genetic complexes to their own – a mechanism that might also help to avoid inbreeding. It’s also unclear whether the rats would succeed in the experiment if presented with odours from men – arguably the smellier members of the human race.

Scientists have a new ally in their battle to understand animal behaviour – a robotically animated dead squirrel. Designed by Aaron Rundus of the University of California, Davis, it is helping to show how California ground squirrels protect their pups from rattlesnakes.

Rundus previously discovered that ground squirrels heat their tails and swish them around, presumably to let an approaching rattlesnake know that they are not to be tangled with. Rattlesnakes are adept at sensing infrared radiation, so would be expected to spot the warning sign. But it was unclear if this supposed signal had any effect on the snakes.

Enter Robosquirrel, a stuffed squirrel featuring a heating element in its tail and a realistic remote-controlled swishing action. When Rundus presented this to rattlensnakes in the lab, they were more likely to coil up or poise to strike in fear. But with the heater turned off the rattlers remained unrattled, showing that the squirrels’ heat-based signalling is a genuine mode of communication. Robosquirrel Mk II is reportedly in development, promising yet more life-like snake-scaring features.

Mating can be a dangerously passionate affair if you’re a redback spider. The pressure to mate successfully inflames males’ passions to such an extent that they rip apart their partner’s exoskeleton in their desire to consumate their union.

Male redbacks embark on the aggressive mating when the female is in the final subadult stage, on the cusp of full sexual maturity, reports Maria Biaggio of the University of Toronto at Scarborough, who made the discovery. This way, they ensure that they are the first to inseminate a female, which is of crucial importance in the face of potential competition from other males. The tactic arose because the odds are stacked against males, for whom the mating game can be a life-or-death struggle – not least because an adult female will often eat him during courtship. Mating of sub-adult females has never before been seen in this species, but it explains why male redbacks are often seen living with juvenile females, says Biaggio – they are keeping a close eye on them until it’s time to mate. Talk about jealous boyfriends…

It might not put Chanel out of business, but for ground squirrels it’s the must-have fragrance of the season. Researchers have discovered that several species of ground squirrel coat themselves in rattlesnake scent to confuse their slithering enemies. The wily squirrels splash on the ‘eau de rattlesnake’ by chewing on the shed skins of snakes and then licking their own fur, giving themselves a coating of snake scent that disguises them from the predators, reports Barbara Clucas of the University of California, Davis.

Ground squirrels are a favourite of animal behaviour researchers because their small size, tameness, complex social communication and wily predator-avoidance tactics makes them good to study. And there’s no shortage of them at the Animal Behaviour Society meeting here in the Utah mountains. The surrounding countryside – and the outdoor terraces of the restaurants – are swarming with them.

Every research field has its buzzwords. And for those who study animal behaviour, the latest one is ‘behavioural syndromes’. It’s kind of like personality profiling for animals, and the concept’s originators hope it will offer more realistic ways to think about their behaviour. And as some researchers point out, it could even shine a light on that most infuriatingly complex of animals, humans.

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