Entry #8: Bipedality and Brain Size

The forces of natural selection that have come to make bipedality are seen to have come from African-ape behaviors that include every day living things such as feeding postures, mating displays and vertical climbing. They also say that it has evolved from chimpanzee like ancestors. One of the main structures that led to bipedality was the big toe, the strong thigh muscles and the strong hips. Organisms then needed to start using their upper bodies to carry things and do other sorts of activities. Being on both legs and upright helped organisms to do activities much easier such as movement. What led to the evolution of larger brain size than our primate ancestor is one of the factors that have affected us is climate. Some scientists think that our brain has become larger because we were thinking ahead of the climate changes that were going to happen so we had to learn to adapt. Another reason our brain may have become larger is because we migrated farther away from the equator and our brain became larger in order to become cleverer and figure more things out. Another factor deals with parasites. Our brain may have become larger in order to fight off parasites. One last factor was the fact that we all had to fight for resources. The more we had to fight for resources, the smarter we had to become in order to outsmart the others.