Osaka, Japan – Researchers at Osaka Metropolitan University have discovered that cleaner wrasse fish can recognize themselves in a mirror and display advanced intelligence similar to dolphins.

In mirror experiments, the tiny fish quickly identified markings on their bodies that resembled parasites and used the reflection to remove them. Some fish responded within the first hour of seeing the mirror, much faster than previously observed in similar studies.

The fish also performed “contingency testing,” dropping small objects near the mirror and watching how their reflections behaved. This behavior indicates they understand the mirror represents real space and shows self-awareness previously thought limited to mammals.

“These findings suggest that self-awareness may not have evolved only in a few species,” said Dr. Shumpei Sogawa. “Mirror self-recognition may be more widespread across animal groups than we imagined.”

The study highlights that even small fish can exhibit complex cognitive abilities, challenging traditional assumptions about intelligence in marine animals. Researchers believe this could have broader implications for understanding animal cognition, welfare, and evolution.

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