Lock eyes with a chimpanzee, and you will notice something is missing. The tissue surrounding their iris, called the sclera, is a deep brown or nearly black. You cannot easily tell where they are ...

Genetics, right? Sort of. Scientists just learned it’s a bit more nuanced than high school biology.

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. This voice experience is generated by AI. Learn more. This ...