Unformatted text preview: light. Upright posture allows a primate to view its surroundings as well as to use its hands for some other task. Hominids, the lineage leading to humans, had changes in the shape and size of their pelvis, femur, and knees that allowed bipedalism (walking on two legs). The change from quadruped to biped happened in stages, culminating in humans, who can walk or run on two legs. Several trends of primate evolution are evident in the teeth and jaw. First, change in the geometry of the jaw reduced the snout into a flat face. Second, changes in tooth arrangement and numbers increased the efficiency of those teeth for grinding food. Third, about 1.5 million years ago our diet changed from fruits and vegetables to include meat....
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- Fall '10
- Biology, eye adapted primates