Читать книгу Anthropology For Dummies - Cameron M. Smith - Страница 87

Brachiation is swinging from one hold (like a tree limb) to another, and the speed champion species here is the gibbon. Southeast Asian gibbons can swing through forest canopy at more than 30 miles per hour, about ten times as fast as most humans walk. Slower brachiators are the big, heavy orangutans, who hang, reach, and shift their body weight instead of really smoking through the canopy like the gibbons. Brachiators have several main anatomical characteristics:

 Long arms: The longer the muscle, the greater its power, so evolution has selected for longer and more powerful arms over time.

 Short, relatively weak legs: These animals don’t spend much time on the ground and really prefer to hang from their hands.

 Very powerful hands: These primates have strong, long fingers but very small thumbs; thumbs would get in the way of the hooking action used to grasp tree limbs and vines.