Cleaner wrasses (Labroides dimidiatus) thrive in coral reefs around the world. But they’re more than just another pretty face among the brightly colored marine ecosystem. Despite their diminutive size ...

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

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 ...