![]() ![]() shoulders and body can rotate without rotating the head.Nuchal ligament helps counterbalance the head.flatter face makes the head more balanced.evaporative heat dissipation from the scalp and face prevent hyperthermia.Selection for anatomical features that made "endurance running" possible radically transformed the hominin body.Ĭompared to Australopithecus fossil skeletons, selection for walking by itself would not develop some of these proposed "endurance running" derived traits. Endurance running hypothesis revisited Premise Īustralopithecus did not have structural adaptations for running. Activities related to short-range hunting and scavenging in the open during the hottest part of the day seem to me sufficient. The comments presented in the article make straightforward objections - "… it is not necessary to postulate endurance running as the cause of increased heat load in early hominins. Something like persistence hunting by hominins created selective pressure for adaptations that improved "endurance running." ![]() (More recent analyses show no statistically significant difference in efficiency to overcome). That the efficiency constraint was overcome suggests that at some point in the evolution of hominins, there was strong selective pressure for "endurance running" - running many kilometers, running for hours, during the heat of the day - until faster prey could endure no more. The relative inefficiency of human running must have been overcome because humans are relatively good endurance runners. However, more recent analysis shows unexpected metabolic changes in human muscle that seem to be linked to a drastic reduction in muscle strength compared to chimpanzees and macaque monkeys. ![]() Human skeletal muscle was thought not to be unusual. The basic capacity for heat dissipation through sweating and hairlessness may be a primitive trait for Old World anthropoids, which enables endurance. However, more recent analysis shows that individual humans do have optimal running speeds they are less efficient when running faster or slower than their optimal speed. The efficiency of human running was thought not to change with running speed, so human hunters could chase at running speeds that were not optimal for the quadrupedal prey. However, in more recent analyses, although 25% lower than predicted for human walking and 27% higher than predicted for human running, there was no statistically significant difference in cost compared to other mammals. Human running was thought to be less efficient than predicted for mammals of similar mass, and yet humans are capable distance runners, which seemed to be a paradox as some modern hunters apparently run prey animals to exhaustion. ![]() Consequently, these evolutionary pressures have led to the prominence of endurance running as a primary factor shaping many biomechanical characteristics of modern humans.Įndurance running hypothesis Premise Īustralopithecus had structural adaptations for upright walking and running that are essentially those of modern humans. Proponents of this hypothesis propose that endurance running served as a means for hominins to effectively engage in persistence hunting and carcass poaching, thus enhancing their competitive edge in acquiring prey. The hypothesis posits a significant role of endurance running in facilitating early hominins' ability to obtain meat. The endurance running hypothesis is a series of conjectures which presume humans evolved anatomical and physiological adaptations to run long distances Īnd, more strongly, that "running is the only known behavior that would account for the different body plans in Homo as opposed to apes or australopithecines". ![]()
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