Brachiation (from "limb" or "branch")'s a form of arboreal locomotion in which primates swing from tree limb to tree limb using only their arms. Brachiators The only true brachiators are the lesser apes (gibbons and siamangs). A gibbon can brachiate at speeds as high as 35 mph (55km/h) and can travel as far as 20 feet (6 m) with each swing. Spider monkeys and orangutans are considered semibrachiators. Brachiation-aiding traits Some of the traits that allow gibbons, siamangs, and other primat… (More on Brachiation)