Puppy-Dog Eyes Didn’t Just Evolve to Influence Humans, Study Finds

Large and droopy “puppy-dog eyes” did not evolve solely in domesticated dogs to appeal to humans, as previously thought, according to a new study that offers fresh insights into canine evolution.

Previous research published in 2019 and 2022 theorized that dogs evolved new muscles around their eyes specifically to facilitate more effective communication with humans. These studies suggested that the development of these muscles allowed dogs to make a wider range of facial expressions, thereby encouraging their human companions to take better care of them.

However, a new study of African wild dogs challenges this theory. The research found that other canine species have similar muscle adaptations that enable them to pull sad-looking expressions.

The latest research, published in the journal The Anatomical Record, involved dissecting a deceased African wild dog (Lycaon pictus) specimen donated by a zoo. The scientists discovered that these wild canines also possess the same “puppy-dog eye” muscles as domesticated dogs. This finding debunks the idea that these muscles evolved solely to influence human behavior, suggesting instead that they may have broader evolutionary significance across different canine species.