Mountain gorillas are the largest living primates on earth! Along with chimpanzees, orangutan, and bonobos, they are the closest living relatives of humans, with mountain gorillas having the most developed brain of the four. They live primarily on the lush mountain sides of national parks in Rwanda, Uganda, and the Democratic Republic of Congo in Central Africa. Mountain gorillas live in groups of roughly 30 members, with one dominant, male troop leader called a ‘silverback’ for the silver color in his coat.