Dogs have a special ability to give the most convincing puppy-dog eyes, a charm that their wild ancestors, wolves, do not possess. This trait can be quite useful, especially when they are up to some mischief. Dogs excel at appearing either completely innocent or very guilty with just one heart-melting look. Whether they have yogurt smeared on their faces from the trash or are surrounded by bits of a torn-up pillow, their expressions often steal the show. Pet owners frequently capture these funny moments and share them online, and Bored Panda has gathered some of the most entertaining examples.
Scientists have found that wild wolves and domestic dogs share nearly all of the same DNA. However, thousands of years of living with humans have altered how dogs express themselves with their faces. For instance, when you come home, your dog might seem to smile, and when they see a leash, they may tilt their head and perk up their ears, as if saying they are ready to go out. If you leave them behind, dogs sometimes press their snouts to the window or rest their chins on the sill, giving a look that many people interpret as betrayal, often referred to as “puppy eyes.”
Researchers have identified a specific muscle that enables this expressive face in dogs, which wolves lack. This muscle, called the levator anguli oculi medialis, is located just above the inner eye. It helps to raise the eyebrows, creating a wider-eyed, more innocent look. In contrast, gray wolves have a minimal amount of tissue in this area, which limits their ability to express the same emotion.
A study led by Professor Anne Burrows at Duquesne University examined the facial muscles of both dogs and wolves. Although both species have similar mouth muscles, dog facial muscles consist mainly of fast-twitch fibers, while wolf muscles have slow-twitch fibers. Fast-twitch fibers allow dogs to make quick facial movements, enabling them to form that appealing puppy-dog face and bark rapidly. Burrows noted that while dogs can show these expressive faces, wolves cannot.
This difference likely emerged during the early domestication of dogs, which occurred around 30,000 to 40,000 years ago. As humans began living with wolves, they tended to prefer animals that could communicate effectively. Professor Burrows suggests that early humans may have chosen dogs with these muscle traits because they could alert them more effectively to potential danger. She indicated that as humans domesticated dogs, they favored those with expressiveness in their faces.
What are your thoughts on how dogs have evolved to communicate with humans?
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Source: Bored Panda, by Danielė Šidiškytė