<Ul> <Li> Hylobates </Li> <Li> Hoolock </Li> <Li> Nomascus </Li> <Li> Symphalangus </Li> <Li> + Bunopithecus </Li> <Li> † Junzi </Li> </Ul> <Tr> <Td_colspan="2"> Distribution in Southeast Asia </Td> </Tr> <P> Gibbons are apes in the family Hylobatidae . The family historically contained one genus, but now is split into four genera and 18 species . Gibbons occur in tropical and subtropical rainforests from eastern Bangladesh and northeast India to southern China and Indonesia (including the islands of Sumatra, Borneo, and Java). </P> <P> Also called the smaller apes or lesser apes, gibbons differ from great apes (chimpanzees, bonobos, gorillas, orangutans, and humans) in being smaller, exhibiting low sexual dimorphism, and not making nests . In certain anatomical details, they superficially more closely resemble monkeys than great apes do, but like all apes, gibbons are tailless . Unlike most of the great apes, gibbons frequently form long - term pair bonds . Their primary mode of locomotion, brachiation, involves swinging from branch to branch for distances up to 15 m (50 ft), at speeds as high as 55 km / h (34 mph). They can also make leaps up to 8 m (26 ft), and walk bipedally with their arms raised for balance . They are the fastest and most agile of all tree - dwelling, nonflying mammals . </P>

Is a gibbon an ape or a monkey
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