Like most animals that thrive in cities, rats get a bad rap. We even use the word “rat” for nasty people, particularly those that go behind your back. But this study suggests that rat society may not be so bad after all. By placing rats in special cages that allow them to give food only to another rat (not themselves), these researchers found that rats will trade grooming for help with getting food. In fact, the more help they got, the more grooming they gave. Maybe it’s time to update the o