A couple of years ago, a report that dogs could “catch” the yawns of their human owners made a big splash in the news media. Here’s a particularly provocative headline:
Dogs ‘may be able to read their owner’s minds’
When you yawn, and then I yawn, you know that I am reading your mind.
While the headline is over the top, it relates back to an hypothesis that the paper made that yawning might spread from humans to dogs because dogs have some level of empathy with humans.
I’m going to jump to the punchline of a new paper by O’Hara and Reeve about this: There is almost no evidence that yawning spreads from humans to dogs. What’s more, this is the second study to fails to replicate the finding that made all the papers.
To go into this in a little more detail, they author were playing around with the idea that dogs catching human yawns might be evidence of dogs’ empathy with humans. If that was the case, you might expect a dog living with an owner presented with a human yawn might yawn than a dog in a pound.
You might expect a dog to yawn more if her owner yawns than if a stranger yawns.
You might expect more empathy between two dogs (being the same species and all) than between a dog and a humans, so dogs seeing another dog yawn would be more likely to respond with a yawn than to a human yawn.
And so it went. There were other comparisons, but O’Hara and Reeve found only very weak evidence that dogs were picking up on any yawns at all. They found an effect only when pooling all the yawning stimuli conditions, and then only for dogs in a rescue shelter, not dogs in their owner’s home. That sort of inconsistency makes me think it might be a false positive, since there doesn’t seem to be a strong reason that dogs in a pound would be more susceptible to catching yawns than other dogs.
This study is almost certainly not going to get the attention that the original one did. “Dogs catch your yawns” is a more compelling story than “Dogs don’t catch your yawns.”
That said, O’Hara and Reeve suggest a great experiment about catching yawns that doesn’t seem to have been done yet:
Do dog owners catch their pets’ yawns?
When is yawning contagious?
O’Hara S, & Reeve A. 2010. A test of the yawning contagion and emotional connectedness hypothesis in dogs, Canis familiaris. Animal Behaviour. DOI: 10.1016/j.anbehav.2010.11.005
Joly-Mascheroni R., Senju A., & Shepherd A. (2008). Dogs catch human yawns Biology Letters, 4 (5), 446-448 DOI: 10.1098/rsbl.2008.0333
Picture by marlana on Flickr. Used under a Creative Commons license.