Quote:Though the 2018 study reported that the fish had passed, the mirror mark test's founder, evolutionary psychologist Gordon Gallup, told New Scientist he believed the fish in these experiments were mistaking the marks on their own bodies for parasites on other fish.

Now, a team from Osaka Metropolitan University in Japan and the University of Neuchâtel in Switzerland has tweaked the experiment to test the wrasse's self-awareness even further.

Quote:"In earlier cleaner wrasse mirror studies, the procedure was typically the fish see a mirror for several days, they habituate to it and stop reacting socially, and a mark is added," animal behavioralist Shumpei Sogawa from Osaka Metropolitan University in Japan explains.

"In this study, the order was reversed; the fish were marked first, then the mirror was introduced for the first time. The fish were likely aware of something unusual on their body, but they couldn't see it. When the mirror appeared, it immediately provided visual information that matched an existing bodily expectation, hence scraping occurred much faster."
While it's far from a perfect control, this goes some way to improving the initial experimental design, giving the fish time to identify the 'parasite' on their own body before encountering their reflection.

The scientists were surprised by how fast the fish reacted in these new experiments: on average, they tried to rub off the 'parasite' within about 82 minutes. This, they say, implies self-awareness before being exposed to the mirror.

After the fish had several days to get used to the mirror, the scientists noticed some performing an unusual behavior. They would pick up a little piece of shrimp from the bottom of the tank, carry it over to the mirror, and drop it.
As the mirror-shrimp fell in sync with the real thing, the fish followed the reflection closely, touching the mirror surface with their mouths.

Sogawa and team believe this is the fish's way of exploring the mirror's properties, using an object separate from themselves to better understand how the reflected images work.




https://www.sciencealert.com/this-tiny-fish-passed-an-intelligence-test-that-once-distinguished-great-apes

(03-10-2026, 06:35 PM)gortex Wrote: The cleaner wrasse spend much of their life providing grooming services for other fish but unknown to their clients they also do a bit of science work in the evenings which seems to prove them smarter than the average fish , in 2018 they passed the mirror test although that was contested by the creator of the test but now a science team from Osaka Metropolitan University in Japan have run an improved test which the little wrasse also aced.

Quote:https://www.sciencealert.com/this-tiny-fish-passed-an-intelligence-test-that-once-distinguished-great-apes

I think it makes sense a fish that puts itself in a potential predators mouth for a living would have have to have some smarts.