Scientists based the research on 20 years of data covering multiple groups of gorillas in Volcanoes National Park, in Rwanda. The scientists found that even when two females had been apart for many years, a newly arrived gorilla would still try to join a female she had formed a previous connection with.

Female mountain gorillas are showing scientists how important friendship can be in the animal world.A long-term study from Rwanda found that when a female gorilla moves to a new group, she