The evolution of eye color in cats has been mapped for the first time, and researchers found that one unusual ancestor is responsible for the feline family’s dazzling variety of peepers — from yellow-eyed tigers to blue-eyed snow leopards.

In the new study, scientists identified different eye colors in living cats and used a computer model to predict where they evolved on the feline family tree. Their model found that the ancestor of all cats must have had gray and brown eyes, and the gray enabled other colors to later emerge.