In theory, a reaction to an out-of-place mark in a reflection is assumed to be evidence of self-recognition for other animals as well. Chimpanzees, elephants, and dolphins are just some that have ...

A small coral reef fish can recognize itself in a mirror. This discovery challenges long-held ideas about animal intelligence.

This small fish shows self-awareness like apes.

A shrimp scrap drifted down the face of a mirror, and a small reef fish tracked it like it was watching a slow-motion ...

Learn how cleaner wrasse used a mirror and even dropped food to test their reflections, a behavior linked mostly to mammals.

Alex Jordan had just surfaced from a dive off the coast of Corsica when he called me back last summer. “We’ve put mirrors in the wild,” he said. “It’s always a bit of a nightmare.” With the help of ...