In fact, the term ape has a history of ambiguity. At one time it was used to refer to any tailless primate which included two species of macaques (neither of which belong to the hominoidea). Two subcategories of apes are also commonly identified, great apes (which includes chimpanzees, gorillas and organtutans) and the lesser apes (gibbons).
Most hominoids, with the exception of humans and gorillas, are skilled and agile tree climbers. Gibbons are the most skilled tree-dwellers of all hominoids. They can swing and leap from branch to branch, moving quickly and efficiency through the trees. This mode of locomotion used by gibbons is referred to as brachiation.
Compared to other primates, hominoids have a lower center of gravity, a shortened spine relative to their body length, a broad pelvis and wide chest. Their general physique gives them a more upright posture than other primates. Their shoulder blades lie on their back, an arrangement that imparts a wide range of motion. Hominoids also lack a tail. Together these characteristics give hominoids better balance than their closest living relatives, the Old World monkeys. Hominoids are therefore more stable when standing on two feet or when swinging and hanging from tree branches.
Like most primates, hominoids form social groups, the structure of which varies from species to species. Lesser apes form monogomous pairs while gorillas live in troups numbering in the range of 5 to 10 or more individuals. Chimpanzees also form troops that can number as many as 40 to 100 individuals. Orangutans are the exception to the primate social norm, they lead solitary lives.
Hominoids are highly intelligent and capable problem solvers. Chimpanzees and orangutans make and use simple tools. Scientists studying orangutans in captivity have shown the capable of using sign language, solving puzzles and recognizing symbols.
Many species of hominoids are under threat of habitat destruction, poaching, and hunting for bushmeat and skins. Both species of chimpanzees are endangered. The eastern gorilla is endangered and the western gorilla is critically endangered. Eleven of sixteen species of gibbons are endangered or critically endangered.
The diet of hominoids includes leaves, seeds, nuts, fruit and a limited amount of animal prey.
Apes inhabit tropical rainforests throughout parts of western and central Africa as well as Southeast Asia. Orangutans are found only in Asia, chimpanzees inhabit west and central Africa, gorillas inhabit central Africa, and gibbons inhabit southeast Asia.
The term ape refers to a group of primates that includes chimpanzees, gorillas, orangutans and gibbons. The scientific name Hominoidea refers to apes (chimpanzees, gorillas, orangutans and gibbons) as well as humans (that is, it ignores the fact that humans prefer not to label ourselves as apes).
Of all hominoids, the gibbons are the most diverse with 16 species. The other hominoid groups are less diverse and include chimpanzees (2 species), gorillas (2 species), orangutans (2 species) and humans (1 species).