A smart fish checks in the mirror if it has the guts to challenge another fish

If you have to fight, you should choose an opponent of your own size. Or preferably a little smaller.

Even the cleaner fish knows this old nakki kiosk wisdom (Labroids halved). According to a new study, it can judge its own size from the mirror and, based on that, decide whether to go on a rampage.

Cleaner fish are molluscs the size of a mullet that live in tropical waters. According to several studies, they are wiser than their small-minded nature suggests.

in Japan researchers showed years ago that a cleaner fish can probably recognize itself in a mirror.

Now the same researchers present Scientific Reports – publication that a fish can also estimate its size in relation to other fish when it first sees itself in a mirror.

Cleaner is a mischievous little fish that takes care of its territory. First, the researchers showed it through the aquarium glass pictures of fish that were either slightly smaller or larger than it. The fish always began to crackle.

But when the fish was placed on the other side of the aquarium with a mirror, from which it could first assess its self-image, it began to challenge only smaller fish.

The essential thing is that the fish did not see its reflection and the image of the enemy at the same time, but had already looked at its own reflection before. So maybe it remembered that hey, I’m this size, I’m not going to go to that corner.

Such with the help of mirror experiments, humans try to evaluate other animals’ awareness and understanding of themselves.

In general, we have not considered fish to be particularly wise, but it may be that we ourselves are fools who do not understand the soul life of fish. We are not always very good at even understanding our own species.

So, before getting into the nightly nakki line, you should read the Japanese study in question to make sure that you still recognize yourself in the mirror the next morning.