Empathy and pro-social behaviour in rats

Rats capable of helping each other from a sense of empathy

source: Ben-Ami Bartal I, Decety J, Mason P.

Science vol 334 no 6061 December 9 2011 pp1427–1430

An experiment to test for helping behaviour motivated by empathy in rats involved placing a free rat in a cage together with a rat trapped in a container. The free rat learnt how to liberate the trapped rat from the container after some days, and could not do this accidentally. The free rat was also allowed to choose between freeing the trapped rat, or eating chocolate from another container. The free rat usually chose to liberate the trapped companion, and more often than not, share the chocolate.  Research shows that rodents suffer distress when they perceive a fellow rodent in distress, and this is called 'emotional contagion', or 'catching' the emotion that you perceive others to be feeling. However the rats in this experiment went beyond emotional contagion, and actively helped their distressed companions. This indicates that rats are capable of empathy and pro-social behaviour, which appears to have biological roots, and can help with the survival of a group. The female rats in this experiment tended to show more empathy than the male rats, in that the females were more likely to free their trapped companion.