Buzz
Light-colored eyes are rare among domestic dogs. A dog with vibrant blue eyes might be seen as strikingly beautiful or even slightly unsettling. The term 'cute' is rarely applied to such eyes, and it turns out that past dog breeders likely shared this view. According to reports from the Smithsonian, recent research suggests that dogs may have been selectively bred for darker eyes to make them seem younger and more approachable.
In their study published in the December 2023 edition of Royal Society Open Science, a group of researchers from Japan examined the difference in eye color between gray wolves and domestic dogs. They reviewed photographs of 22 wolves and 81 dogs from 35 breeds, revealing that dogs' eyes were generally darker. While dark brown is the most common eye color in dogs, wolves' eyes are more typically yellow.
This variation might have been a result of human selection. After studying canine eye colors, the researchers asked participants to view dog images and make personality judgments. Some of the photos were modified to alter the lightness or darkness of the dogs' eyes. Dogs with darker eyes were often perceived as friendlier, more sociable, and trustworthy, whereas dogs with lighter eyes were seen as more aggressive and mature. This suggests that humans find brown eyes appealing and youthful, potentially explaining breeders' preference for the trait.
It's not the color of the eyes that we find irresistible, but the perceived size of the pupils. Humans are born with relatively large pupils that shrink as we age and our eye muscles weaken. We associate larger pupils with youth, and the darker the iris, the less noticeable the pupil. The study authors believe that brown eyes make pupils seem larger than they really are, tricking us into thinking our pets are helpless babies in need of protection—even if they’re 85-pound Labradors.
Color isn’t the only factor that makes a dog’s eyes appear larger and more endearing. Over time, domestic dogs have developed the ability to raise their eyebrows when gazing at their owners, a behavior we call puppy dog eyes. Here are more facts about puppies you should know.
