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

Cleaner wrasse quickly learn to recognize themselves in mirrors, and take advantage of the information their reflection provides. They also experiment with the mirror in a way we might call playful, ...

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 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 ...

Manta rays may be much smarter than their lumbering, undulating appearance suggests. Two of the winged fish were observed waving at themselves in mirrors and behaving in ways that hint at ...

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

Daniel Povinelli was in high school when he first read about a clever experiment, published in 1970, that showed chimpanzees—but not monkeys--can recognize themselves in mirrors. "I bought into the ...