Any of the tailless, anthropoid primates of two families: Hylobatidae (the lesser apes: gibbons and siamangs) and Pongidae (the great apes: chimpanzees , bonobos , orangutans , and gorillas ).
Apes are found in the tropical forests of western and central Africa and South Asia. They are distinguished from monkeys by having no tail, having an appendix, and having a more complex brain. Apes typically move about by swinging, and they tend to stand erect, occasionally walking on two feet. Highly intelligent animals, apes are more closely related to humans than are any other living primates. As a result of habitat destruction and hunting, all the apes are now regarded as endangered.