After analyzing photos of 22 wolves and 81 dogs across 35 breeds, they found that the dogs’ irises were notably darker on average. While dark brown is the standard eye color in dogs, wolf eyes ...

Key points. Most wolves have light, often yellow-colored eyes, while most dogs have brown eyes. Human observers tend to rate dogs with darker eyes as friendlier and more puppy-like.

A team of scientists from Japan analyzed images of 22 grey wolves and 81 domestic dogs (including 35 major dog breeds) and found that dark irises were more common in the latter.

American author and humorist John Kendrick Bangs wrote: "I have no dog, but it must be / Somewhere there's one belongs to me. / A little chap with wagging tail, / And dark brown eyes that never ...