Ever wonder why your dog always seems to look sad, or apologetic? Believe it or not, those ‘puppy dog eyes’ may have more to do with their human companions than with their canine DNA.
In a recent study published in the journal Proceedings of the National Academy of Sciences, researchers found that those puppy dog eyes are only possible because of a very strong muscle that appears to have evolved specifically to mimic human emotion.
Researchers surveyed both dogs and wolves and found that this ’emotion muscle’ was “uniformly present” in domesticated dogs, but never present in wolves. In five out of six dog breeds tested this eyebrow-lifting muscle was fully developed and more than capable of lifting the eyebrows in an exaggerated fashion. This muscle was either absent or poorly developed in both wild wolves and their closely related cousin – the Siberian Husky.
Based on the study, researchers hypothesize that the domestication of dogs some 30,000 years ago, likely was the catalyst for the evolution of this muscle. They further suggest that the ability to raise the eyebrows in this way allows dogs to communicate more effectively with their human companions.
While the study was small and more research is necessary to prove the hypothesis, the results are nearly as compelling as those big sad eyes that your Great Dane uses to earn doggy treats and escape punishment.