Researchers at Osaka Metropolitan University in Japan have discovered a previously undiscovered behavior in cleaner wrasse (Labroides dimidiatus). When presented with a mirror, the tiny fish not only ...

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

A grouper and a moray eel sound like an unlikely pairing, but they form the ultimate hunting team thanks to referential gestures.

Before squaring up for a fight, some fish check themselves out in the mirror to make sure they're big enough. This strange behavior was seen in bluestreak cleaner wrasse (Labroides dimidiatus), who ...

Two species of small, deep-dwelling fish called pearlsides possess eye cells that break the rules of vertebrate vision, combining features of rods and cones into a single hybrid photoreceptor never ...

For many animals, siblings are a key component of their social environment during early life. Previous research has shown ...

A month ago, I took a walk through the edge of San Francisco’s Golden Gate Park. I was off the main road, on a dirt and gravel trail. So it was strange to look ahead and see that fish were blocking my ...