L48 Anthro 150A Lecture Notes - Lecture 33: Ardipithecus, Pelvis, Foramen Magnum
Document Summary
2 ideas to explain dwarfism it is a case of pathology- genetic differences island dwarfism, dwarfed population of homo erectus. Experimental biology approach to answering questions on human evolution. Highly arboreal bipedal ape could have been our last common ancestor. Evidence: gibbons walk on the ground bipedally with arms raised because it is more comfortable for them. Places hip-stabilizing muscles on the side, helps us stand on one leg at a time. Our legs have gotten longer relative to our arms. Tells us selection has favored efficient pushing off the ground over grasping of feet: humans have rigid arch in the foot- spring-like. Human evolutionary story is 6 million years long: 3 distinct chapters, 1. early homonin chapter, chad skull, ororrin, ardipithecus, 2. Why did bipedalism evolve: energy efficiency-easy to test, free hands for tool use-false, vision- predation- , solar radiation- probably not, carrying food back to mate-, aquatic lifestyle-false, new niche.
