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 ...

Here’s what you’ll learn when you read this story: Eye color comes down to a pigment called melanin. The more melanin your irises produce, the darker your eyes. Your genes are the main thing ...

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Add Yahoo as a preferred source to see more of our stories on Google. The white part of our eyes is known as the sclera. Blue, green, amber: Someone's eye color immediately attracts our attention. But ...