Bluestreak cleaner wrasse found to recognize self in photograph after passing mirror test

[USCfan]

Very interesting read. Wonder if the glass itself does the same thing or do you need a mirror in the tank.

Bluestreak cleaner wrasse found to recognize self in photograph after passing mirror test

A team of biologists at Osaka City University, working with a colleague from the University of Neuchâte, reports that a type of cleaner fish can pass the mirror test and then recognize itself in a photograph. In their paper published in Proceedings of the National Academy of Sciences, the group...

phys.org

The researchers placed a mirror in a tank with several of the fish for a period long enough to allow them to acclimate to seeing themselves reflected. They then removed the mirror and replaced it with a picture of the same fish with a mark on its face. The fish responded by trying to remove the mark. The researchers also placed pictures of other similar fish in the tank with the same mark on their faces. The wrasses attacked them, seeing them as rivals.

 

[Timfish]

Yeah, that paper has gotten a lot of discussion.

As far as the fish seeing a reflection of itself it can see out as well as we can see in. The reflections we see looking into a tank is an optical effect seen from outside the tank. An observer inside the tank doesn't see it.