moving slower with a lower energy recovery and more control likely outweighs the cost of extra energy expenditure. Evolution of brachiation Brachiation originated in Africa, thirteen million years ago. The emergence of bigger primates that learn to move hanging around by branches obliges the new generations to make some corporal changes that have lasted until today, in many species, including the humans. Specialized locomotor behaviours, such as brachiating, are thought to have evolved from arboreal quadrupedalism. This behaviour is the ancestral and most common locomotor mechanism among primates. This would explain why living apes and humans share many unusual morphological aspects of the upper limb and thorax. The transition to brachiation is regarded as a major shift during primate evolution and is thought to be a possible precursor to the adaptation of bipedal walking in early hominids. Specialized suspensory behaviour was shown to have evolved independently between hominid groups. There are several hypotheses for how early brachiating primates may have transitioned into bipedalism. The most generally accepted of these is the vertical climbing hypothesis, which states that vertical climbing is the biomechanical link between brachiation and bipedalism. Many climbing adaptations have been found in early hominins and some of these adaptations can still be seen in present day humans. The distinctive body posture, limb proportions and trunk design identified in living apes are better explained by the previous adaptation of climbing behaviours. See also Suspensory behavior Arboreal locomotion References Arboreal locomotion Primate behavior