Ape years ago (Mya) the clades diverged into newer clades. The lesser apes are the gibbon family, Hylobatidae, of sixteen species; all are native to Asia. Their major differentiating characteristic is their long arms, which they use to brachiate through trees. Their wrists are ball and socket joints as an evolutionary adaptation to their arboreal lifestyle. Generally smaller than the African apes, the largest gibbon, the siamang, weighs up to ; in comparison, the smallest "great ape", the bonobo, is . Formerly, all the great apes except humans were classified as the family Pongidae, which conveniently provided for separating the human
Ape index Deadlift, where longer arms reduce the range of motion required to complete the lift . Ape index Ape index, or ape factor factor, or gorilla index is slang or jargon used to describe a measure of the ratio of an individual's arm span relative to their height. A typical ratio is 1, as identified by the Roman writer, architect and engineer Vitruvius prior to 15 BC. Vitruvius noted that a "well made man" has an arm span equal to his height, as exemplified in Leonardo da Vinci's drawing, the "Vitruvian Man". In rock climbing it is believed that an Ape