دانلود کتاب میل نوع دوستی – چرا ما رانده شده ایم تا به دیگران کمک کنیم

In a now- classic study conducted in 1969, a physiological psychologist at San Fernando Valley State College, William E. Wilsoncroft, was studying mother rats’ motivation to retrieve their newborn pups. Before this study, research spanning back to the early twentieth century had already shown that such maternal rat “dams” are highly motivated to approach and contact their own pups. They will even retrieve the new pups of another dam to which they are not even related. This research documented that the instinct to retrieve pups was strong enough that the newly maternal dams were willing to learn complex mazes in order to gain access to young pups, and they even walked across electrified grids to reach their litters. The new moms were literally accepting electric shocks to access pups. Testifying to the relative strength of this motivation compared to other enticing rewards, dams were more willing to cross an even higher number of these electrified grids to access their litter of pups than to receive food, drink, or even sex. This instinct— referred to in scientific studies as “offspring retrieval”— is pronounced in these rats on the days immediately after giving birth.