The bluestreak cleaner wrasse can use a mirror to assess its own size and avoid territorial squabbles with much larger rivals, a Japanese team of researchers said Wednesday.

Found in rocky areas and coral reef in areas south of Chiba Prefecture, the bluestreak cleaner wrasse, which is a small fish measuring around 10 centimeters long, is already known to be a creature that can recognize itself in mirrors and photographs, like humans can.

The bluestreak cleaner wrasse, which eats parasites off of other fish, engages in fierce territorial battles.