Empathic rats spring each other from jail

You enter a room with two cages. One contains a friend, who is clearly distressed. The other contains a bar of chocolate, which clearly isn’t. What do you do? While a few people would probably go for the chocolate first (and you know who you are), most would choose to free the friend. And so, it seems, would a rat.

Inbal Ben-Ami Bartal from the University of Chicago found that rats will quickly learn to free a trapped cage-mate, even when they get nothing in return, or when there’s a tasty chocolate distraction around. Bartal thinks that the rats conduct their prison breaks because they empathise with one another. This ability to understand and share the feelings of another individual is found in humans, apes, elephants, dolphins and other intelligent animals. It seems that rats belong in this club too.