ANT 101 Lecture Notes - Lecture 3: Foramen Magnum, Flat Feet, Ardi
Document Summary
Oldest humans is the sahelanthropus around 7-6 myo big brow bones. Can choose to walk on two or four legs/limps (chimps and apes) can easily walk. More energy effective walk on two legs no other reasonable alternative(very distinctive to hominin) Foramen magnum at base of skull instead of the back means. Spine s- shape (acts as a spring or cushion) vs flat and straight as it is parallel to the ground. Pelvis is short and broad (makes energy effective to be small and act as two legs) vs elongated. Femurs angle inward angles knee which makes it easy to balance on one leg so walking is possible (controlled falling) Foot with arch that gives a spring board that allows body to be propelled forward vs flat feet with grasping and divergent toes to climb trees. We walk with backs verticals whereas other bipeds walk with backs close to horizontal.
