Novosibirsk scientists raised civilizations of good and evil rats to understand the nature of aggression

In Novosibirsk , at the Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, “civilizations” of good and evil rats were grown in order to understand the genetic nature of aggression. This is stated in an article published in mk.ru.
As the article says, this experiment, which has been carried out at the institute for 50 years, is the only one in the world. It involves the descendants of gray street rats. Evil individuals were put in one cage, sympathetic to people – in another. And so they did with several generations of their offspring for several decades. The propensity of a rat to one or another type of character is determined by its reaction to the employee’s hand stuck in the cage, if the animal approaches it, is interested, sniffs it, it is determined in one direction, if it immediately pounces and bites, it is in the opposite direction.
In February, the institute’s vivarium reported the arrival of the 100th generation of benevolent rats. In all 200 rats, the “diagnosis” was maximum goodwill with estimates from +3.5 to +4 points, while in their ancestors it averaged from -2.5 to -1.5 points. The average scores of aggressive rats dropped to -4 points.
The scientists also tried to test whether a benevolent environment could affect the children of aggressive parents, for this they planted rat pups from aggressive parents to benevolent mothers, and tame ones to aggressive ones. However, biologists have come to the conclusion that sympathy and aggression were fixed at the genetic level. Only a few cases have been recorded when an aggressive couple gives birth to a cub that is slightly less aggressive than them (the aggression score in such cases was reduced by one compared to relatives).
Earlier it was reported that biologists found that the coronavirus can spread in gray rats.