Published: Dec 08, 2011 8:34 PM EST

WASHINGTON (AP) - New experiments show that rats, despite their selfish reputation, don't act like, well, rats.
    
Instead, rats can be compassionate. They freed another trapped rat in their cage, even when yummy chocolate served as a tempting distraction. Twenty-three of the 30 rats in the study opened the cage. The rats could have hogged all the chocolate before freeing their partners, but often didn't, choosing to first help, then share.
    
Study author Peggy Mason of the University of Chicago said females showed more empathy than males. All six females freed their trapped partner; 17 of the 24 males did so.
    
Mason said the study showed that pro-social empathy is not limited to humans and primates as some people had thought. The research is reported in Thursday's journal Science.

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