What were the selection pressures that produced bipedal locomotion in hominids?

Answer 1

An Ice Age caused a reduction in the amount of liquid water available globally. The African forests began to dry up and turned into savannah with clumps of trees. Food was scarcer. Our ancestors had to forage farther and farther out into the dangerous, predator-rich savanna to find food. Bipedalism freed our hands for a new purpose (not locomotion but carrying). Being able to dash fom clump to clump of forest while carrying lots of food was critical to to the survival of one's self and one's family.

Answer 2

very difficult question