Study: Dogs Evolved to Use Eyes to Connect with Humans
But a new study found evidence that dogs developed in physical ways to present “puppy dog eyes” as a way to help connect with humans. Researchers in Britain and the United States did the study. Results were published in the Proceedings of the National Academy of Sciences (PNAS).
The study compared the facial muscles of dogs and wolves, which share ancestral history. Dogs broke off from wolves after being domesticated about 33,000 years ago. During that time, dogs changed physically and behaviorally to fit life with humans.
The researchers examined the heads of six dogs and two wolves for comparison. They found the facial structure of both animals was mostly very similar. But one major difference was found above the eyes.
The dogs were found to have two well-formed muscles around the eye that were not present in the wolves. These small muscles permit dogs to “intensely” raise their inner eyebrow, the study found.