During a simple experiment, researchers at the University of Chicago found that a free rat works tirelessly to release a fellow trapped rat.
Empathy and pro-social behavior to help others were previously thought to be unique to humans. But this new experiment shows the roots of human empathy evolved with time.
3-years of repeated experiments revealed that rats would release a fellow rat from an unpleasantly restrictive cage if it could, despite being offered tempting distraction like yummy chocolate. After hearing distress calls from its fellow rat, the free rat learned to open the cage and did so with greater efficiency over time. It would release the other rodent even if there was no payoff of a reunion with it. Also, if rats were given access to a small hoard of chocolate chips, the free rat would usually save at least one treat for the captive rat. Female rats showed more consistent empathy than males
The findings of study are published in the research journal Science.