The Evolution of Bipedalism

common ancestor

of humans and chimpanzees likely lived about 5-7 million years ago and would have been quadrupedal (walking on all fours)

Thermoregulation

better heat dissipation in open environments

make provisioning theory

Early males might have carried food back to females and offspring, leading to selection for upright walking

how is the pelvis in Australopithecus afarensis different from Homo sapiens

• became broader and more bowl-shaped to support internal organs and help with balance during walking. This also helped stabilize the body’s weight while standing on one leg

• to adapted for both climbing and walking

how is the spine in Australopithecus afarensis different from Homo sapiens

• curve acts as a shock absorber, helping to distribute the weight of the body while walking upright

• helped with climbing

improved mobility

Bipedalism helped early hominins move efficiently across the landscape, giving them an advantage in the open savannas and grasslands

increased visibilty

Standing upright allowed early hominins to see over tall grasses, helping them spot predators or prey at a distance