UK:HUMANS MAY not be the only ones to find yawning contagious. New research has found that a yawn is likely to set off pets as well as people around you.
Psychologists found that dogs were far more likely to break into a yawn if they witnessed humans simulating the action. The finding is the first evidence to suggest animals other than primates may be susceptible to catching yawns.
Atsushi Senju, who led the study at Birkbeck, University of London, said dogs' ability to catch yawns suggested they may be better at empathising with humans than previously thought.
Yawns improve blood flow in the brain and boost alertness, but why they should be contagious is less well understood. Some scientists argue that the ability to catch yawns arose in early humans as it helped keep tiring groups alert or signalled when it was time to rest.
A previous study by Dr Senju found that people with autism do not find yawning contagious, while other researchers have shown that those who do tend to score more highly in social awareness tests.
In the latest research, Dr Senju's team recruited 29 pet owners and their dogs.
Each dog sat through two tests. In the first, scientists simulated a loud, vocal yawn every time the dog made eye contact. In the control tests, scientists opened their mouths, without making a noise.
"When the experimenters mimicked yawning, 21 out of 29 dogs showed contagious yawning, so this is a very strong and reliable effect," said Dr Senju, whose study appears in Biology Letters. "None of the dogs in the control group yawned. We know contagious yawning is linked to empathy, so it may mean dogs can empathise well with humans, but we need to do more tests to be sure."
While it is possible the dogs were simply copying the yawning movement, Dr Senju said it was unlikely as dogs usually need to be trained to copy human actions.
- (Guardian service)