Origins of hominid bipedalism Essay Example | Topics and Well Written Essays - 500 words

Origins of hominid bipedalism - Essay Example The other great apes for example chimpanzees do not have a straight gait and human straight gait is much more efficient than their bipedalism and quadrapedalism. Fossil evidence of hominid ancestor’s bipedalism is constructed to imply that it existed about 3.5 million years ago. This essays objective is therefore aimed at looking at two distinct hypotheses that attempt to provide explanations to the origins of hominid bipedalism. The first hypothesis (from empirical evidence) to propose is that bipedalism evolved because of energetic efficiency needed by the hominid for travel and that the need was key to the origin of bipedalism. To accept the hypothesis above, first the comparisons should be made at constant speeds of travel and given that bipedal hominids descended from quadrapedal hominids the comparison should be between bipedal hominids and quadrapedal hominids. Rodman and McHenry( 104) observed that male chimpanzees traveled a median speed traveled a median speed of 3.8, 4.2 and 6.4 km each day in three different seasons and took 59 minutes, 105 minutes, and 148 minutes respectively to travel those distances. On average, the male chimpanzees travelled at a speed of 2.9 kilometers per hour, a normal human being walks at an average speed of 4.5 kilometers per hour. Modern hominids through adaptive features evolved bipedalistic tendencies to suit their current environment this explanation is provided wit hout reference to any empirical observation. The result show that there was no energetic difference separating hominid quadrapedal adaptation from hominid bipedalism. It is widely accepted that bipedalism arose because the hominid ancestors moved from living less on the trees to be more comfortable on the ground this was because of hominid dietary divergence (Lewin 113). The Lovejoy hypothesis postulates that the primates underwent evolution to achieve reproductive success through reduced parental care, pregnancy and maturation period. As the