Gorillas are the largest of the 4 species of great ape. They inhabit West, Central and East Africa from Cameroon to Rwanda. They are under threat because humans, in particular poachers, kill them for their meat and body parts and sell them on the black market. In spite of their large size, gorillas are gentle, docile animals and only attack if they perceive something as a threat. Their DNA is about 95% of those of  a human, with chimpanzees being more closely related.