Prairie dogs perform contagious Mexican wave
It looks like a slightly comical Mexican wave, but researchers think a bobbing display seen in black-tailed prairie dogs could prevent the rodents being eaten.
These "jump-yips", as they are known, are initiated by one animal, and spread throughout the group.
In a study, scientists concluded that the animals use jump-yips to "test" the alertness of their neighbours.
Prof Jim Hare from the University of Manitoba in in Winnipeg, who led the study, described this contagious behaviour as the animals' way of "testing the emergency broadcasting system".
End Quote Prof Jim Hare University of Manitoba
Contagious behaviour is a way of assessing the minds of others”
He told BBC News: "The conventional wisdom is that it's an 'all clear' signal"; it was thought to be a visible and audible sign that it is safe for the group to keep feeding and that there are no immediate threats, such as nearby predators.
"But when I was watching them in the zoo, I noticed they would do it when there were crows around, which are potential predators.
"They just seemed to be doing it intermittently."
So Prof Hare and his colleagues set out to find out if the prairie dogs that instigated a bout of jump-yips changed their behaviour according to how the rest of the group responded.
"You would expect to see foraging behaviour increase and vigilance decrease when the rest of the animals respond," he explained. "And that's exactly what we found."
The scientists filmed the displays and discovered from their footage that when the group responded with a "Mexican wave", the prairie dog that had initiated the display spent more time foraging before it "jump-yipped" again.
"It really suggests that these animals are assessing others," said Prof Hare. "They're relying on their neighbours, just like we do."Consciousness or cues?
Other animal behaviour experts pointed out that there were more questions to be answered before it became clear that the prairie dogs were truly conscious of how other individuals were behaving.
One researcher said the prairie dogs could be following "simple cues" to pick up on the actions of the rest of their group.
Dr Alan McElligott from Queen Mary University of London, who studies animal behaviour, said the research was very interesting. And he commended the team for revealing their insights by studying animals in the wild.
"It would probably be impossible to create a experimental set-up that would mimic anything like this for a prairie dog," he said.
Dr McElligott added that there were "lots of other questions [about the behaviour] to be answered in future".
Prof Hare agreed that more detailed study would help scientists to work out the rules behind these displays.
But, he added, "like yawning in humans, such contagious behaviour is a way of assessing the minds of others, and understanding of a mind that's distinctive from our own".