But now, incredibly, new research suggests that the cleaner wrasse—a tiny, tropical reef fish—can recognize itself too, making it the first fish to do so. Scientists have long used a mirror ...

On the Great Barrier Reef, bluestreak cleaner wrasse establish “cleaning stations” where larger fish allow the wrasse to feed on dead skin, loose scales, and invertebrate parasites living in their ...

A bluestreak cleaner wrasse at work cleaning the mouth of a goatfish. (Wayne and Pam Osborn/iNaturalist, CC BY-NC) On the ...

On the Great Barrier Reef, bluestreak cleaner wrasse establish “cleaning stations” where larger fish allow the wrasse to feed on dead skin, loose scales and invertebrate parasites living in ...

On the Great Barrier Reef, bluestreak cleaner wrasse establish “cleaning stations” where larger fish allow the wrasse to feed on dead skin, loose scales and invertebrate parasites living in ...

Yet this coral graveyard I’m exploring has only refugees. I see a fish called a cleaner wrasse and feel a pang of sorrow. Its role in the reef ecosystem is to clean other fish, nibbling ...