Rats May Take into Account Dtheir Own Body Weight

In animals, the awareness of own body is expressed in their ability to take into account various parameters of their bodies in the relationship with the environmental objects. Currently, one of the areas of these studies is the ability of animals to perceive their bodies as a physical obstacle to solve a problem. We studied the ability of brown rats to consider their own body weight. To solve the experimental problem, the rats were supposed to receive the bait by crossing one of three bridges located above the floor. The bridges could be installed in a fixed or unfixed position. In the second case, when the rat tried to cross the bridge, it fell. Accordingly, the rat needed to correlate its body weight with the strength of the support. We found that 14 out of 41 tested rats could solve this problem. During the experiment, these rodents demonstrated characteristic “trying movements”, during which, we believe, they correlated their own weight with the reliability of the bridge.

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