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

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

Cleaner wrasse have revealed a remarkable new side of fish intelligence. Marked with fake parasites, they used mirrors to inspect and remove the spots—far faster than seen in earlier tests. Even more ...

In the current study, the scientists observed new behaviors during a series of mirror test experiments, a widely used method ...

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