Moving from the ground to the trees caused
S-shaped spine (more stability)
Ilium short (pelvis bowl shaped-not elongated)
Legs longer (increased stride)
Knees angled inward (place feet beneath center of gravity)
Longitudinal foot arch (leverage and shock absorbing)
Big toe not opposable (support body – not grasping)
As forest fragmented, bipedalism freed the hands to pick up food allowing for both tree and ground food resources to be exploited.
“Provisioning” form of sexual competition among males for females.
Birth spacing would also be reduced, since females would have to move around less and would have access to greater food resources.
Hypothesis makes the argument for monogamous fathers.