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

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

Animals have surprised scientists with their intelligence for decades. From chimpanzees to dolphins, many species have shown they can recognize themselves. Now, a small fish called the cleaner wrasse, ...

Forbes contributors publish independent expert analyses and insights. I write about biodiversity and the hidden quirks of the natural world. For decades, self-awareness has been guarded as a very ...