New research seems to demonstrate that a fish called the cleaner wrasse has passed the famous mirror test for self-recognition—and the results have ignited discussion about animal intelligence and the meaning of the test itself.

But individuals from some species seem to figure out that they’re looking at themselves, including some chimpanzees, elephants, dolphins, magpies, and, of course, humans, leading us to believe these animals possess a concept of “self.” Scientists are now wondering: Has the most recent research sufficiently demonstrated that a fish species passes the test?

“But if you educate yourself on what these animals can do, it shouldn’t be surprising that they can do something more complex.”

Psychologist Gordon Gallup first published the results of a mirror test in 1970 in the journal Science.

Gallup introduced a mirror into the cages of four wild-born chimps.

They observed the chimp not touch their faces until they put the mirror back next to the cage, after which the chimps tended to the marks.

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