Zebra mbuna is. It lives in Lake Malawi in east-central Africa. Its length does not exceed ten centimeters. Lives in colonies organized according to an established hierarchy. And, if it is harmless for us, people, he does not like, but does not like at all that an uninvited guest is trying to breed on his territory.
, it lives in the Atlantic Ocean and the Mediterranean Sea. Including the tail, it can reach two meters in length. This is a solitary fish that likes to hide in the sand. And if you approach her, she can get scared and straighten the stinger on her tail to sting you and inject a poison that can be deadly.
Presented in this way, the two fish seem to have nothing in common. However…
Before going any further, it’s important to clarify that researchers have long known that some fish have a sense of number. They are not the only ones in this case in the animal kingdom. Far from there. This ability is present in all classes.. And even in some . Bees, for example. They are even capable of performing simple calculations.
What if the bees…also, it seems – you know how, so why not fish? This is the question the researchers asked themselves. And to answer it, they decided to work with… a zebra mbuna and a stingray. Because in terms of numbers, these two are surprisingly very similar to us. shot to a small amount of coins on the ground, and they immediately know how many there are. Probably without the need to count.
So the researchers wanted to know if they could train these fish in. Practice addition and subtraction. Very simple. Operations that add or remove only “one” from the original quantity. And it worked!
How ? Following the samethan the one used to show the computational abilities of the bees. The researchers presented to fish. With code : blue for addition and yellow for subtraction. So, when the fish were presented with four blue squares, they should have moved on to a group of five squares. That’s four plus one. Of course, with a gourmet award at the end of the day.
To make sure the fish didn’t just associate the color blue with more, the researchers presented them with three blue squares, with a choice between four or five squares afterwards. The fish made the right choice. Proving they didn’t learn the rule “choose the largest or smallest amount”but the rule “add — or subtract — one”.
Surprisingly, the fish continued to be strong in calculations, even when the researchers presented them with objects of various shapes. Understand that then the four can be quite well represented by a small and large circle, a square and a triangle. Proofincredibly effective for these little beasts that don’t even have . This part involved in complex cognitive tasks in mammals. And who a priori does not need to develop this kind of ability in nature. More proof that the zebra mbuna and the stingray… are not that stupid after all!