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 ...

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

People are eating more and more fish. To meet rising demand, fish are increasingly being cultivated in fish farms. Aquaculture is the fastest-developing branch of the global food industry, with annual ...