A new study by researchers from Portugal bring even more evidence of altruism in these animals. Experimenters placed rats into pairs and provided one of the rats a choice: open one door and get a food morsel for yourself; open another and both rats receive a reward. Out of 15 rats tested, all but one made unselfish choices consistently. The rats in fact selected the prosocial outcome around 70 percent of the time.
Disclaimer: Stop UBC Animal Research does not condone or endorse any animal experimentation.