No two people in the world have the same color eyes. Experts weigh in on the genetics that cause the rarest eye color in the world...plus, what can cause our eye color to change.

Cat-like eyes show up in searches everywhere. If the internet is this obsessed with eye color, how rare are green eyes in humans? They're uncommon enough that seeing them still feels like spotting a ...

Forbes contributors publish independent expert analyses and insights. I write about biodiversity and the hidden quirks of the natural world. For most of human history, green eyes didn’t exist.