Gray and green eye colors are the rarest in the world. Eye color is determined by the amount of melanin in the iris, with more melanin making eyes darker. A genetic mutation 10,000 years ago caused ...

Do you have dark brown hair and brown eyes? Then you have something in common with most people around the globe. According to the World Atlas, about 90% of the global population has dark brown or ...

When it comes to dogs, you've probably noticed that most of them have brown eyes, which is why meeting one sporting a different shade really makes them stand out. While you've probably seen a few pups ...