Characteristics Of Bipedalism

Two of the most distinct features that separate humans from the other great apes are bipedalism and large brain in relation to body size. But how did these features become so prominent in humans? Approximately 6-7million years ago, the hominid lineage began to diverge from the other great ape species. Tracing the evolutionary history through fossil evidence explains how early hominids evolved to become today’s most prolific primate species. The goal of this paper is to discuss the physical characteristics that indicate the evolution of bipedalism and large brain size in the hominid line. To achieve this I will address the anatomical differences that evolved between humans and apes to make bipedalism an efficient form of locomotion, the increase of brain size,

Many adaptations occurred to allow humans to walk upright. For example, unlike apes, our arms are shorter and weaker than our legs. The human pelvis became wider, shorter, and more curved compared to our evolutionary relatives to provide more stability while walking and running. Spinal modifications, such as a centered foramen magnum, increase the support needed to maintain a vertical position. The femurs in humans are much longer and farther apart at the hips, but adduct inward making them narrower at the knees. “This angle allows anthropologists to diagnose bipedalism even if the fossil is only the knee end of a femur.” (Singh, 39). Human feet evolved to provide greater stability and equal weight distribution by acquiring an arch, and the big toe moving inward to be in line with the other toes, and increasing in length. These anatomical modifications allowed early humans to move more efficiently with less energy expenditure, thus capacitating them to traveling further distances. With mobility, came the expansion of environment and new resources, which contributed to the progression of the