Tuesday January 6, 2026
Forbes —
For decades, self-awareness has been guarded as a very exclusive club within the animal kingdom. Only a handful have been recognized to be part of it. A few great apes. Dolphins. Elephants. One bird. Researchers had low expectations for any other animal, from rodents to reptiles to fish, to join this group. Then, in 2019, a small reef fish with a neon-blue racing stripe forced them to reconsider.
The bluestreak cleaner wrasse (Labroides dimidiatus), rarely longer than a human finger, became the first fish ever reported to pass a classic test of self-recognition. This claim, on its own, was provocative enough to spark immediate controversy. Fish are purported to be reflexive, forgetful and cognitively simple; they certainly aren’t known for being self-aware.