This tiny fish can recognize itself in a mirror. Is it self-aware?

The cleaner wrasse joins humans, chimpanzees, dolphins, and a select few other animals that can pass a long-standing intelligence test.

It’s almost automatic—if you notice a smudge when you look in the mirror, you wipe it off. Seems simple, but only a few particularly clever species such as orangutans and dolphins share this ability with humans.

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 test to evaluate whether an animal is capable of visual self-recognition—and potentially self-awareness. Self-awareness involves having a working knowledge of your own mental states, like thoughts and emotions, along with an understanding of how you physically appear; self-recognition, in contrast, is limited to knowing the latter. It’s unclear how much self-recognition implies self-awareness.

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