Darwinian Evolutionary Theory and Bipedalism of Hominins

Darwinian Evolutionary Theory
Name
Institutional Affiliation
Darwinian Evolutionary Theory
Introduction
Paleontologists often regard bipedalism as an unusual and highly specialized locomotion type in modern humans. While the majority of members in the extinct primate taxa of Hominin were largely bipedal, the extent to which these members were bipedal has remained a contentious issue. Besides, although the early records of hominin fossils are obscure, evidence exists that there are at least two distinct shifts in adaptions. The first shift was the move to habitual bipedalism as witnessed among the Australopithecus members as well as other earlier genera, including the Orrorin and Ardipithecus. These taxa were largely bipedal although they retained several important adaptations to arboreal climbing. The other shift was to completely obligate bipedalism and this coincides with the emergence of the Homo genus. During the Pleistocene period, certain members of the genus had already acquired a postcranial skeleton, which denotes a fully striding bipedalism witnessed among modern humans. Bipedalism is known as a defining feature among humans, and while walking on two feet has been documented throughout history, the reconstruction of hominin gait evolution is overly complicated due to sparse fossil record and difficulties in inferring biochemical patterns from fragmentary and isolated bones (Hatala et al., 2016). Nevertheless, fossil evidence and the logic of the Darwinian evolutionary theory show that the development of bipedalism offered hominins competitive advantages in carrying tools, traveling over long distances, and seeing over tall bushes.
Homo sapiens are obligate bipeds, and unlike other mammals that are habitually upright such as kangaroos, springhares, and jerboas, humans are the only extant mammals known to habitually stride only on their extended hindlimbs (DeSilva & McNutt, 2018). Facultative bipeds such as pangolins, modern apes, and some bears infrequently stride on two feet in their short bouts of location. Although it remains unclear about the purpose of bipedalism evolution, palaeontologists have explained two main reasons for this emergence. First, the trait relieves the upper limb from the function of locomotion and this offers a form of transport with the creation and overall reliance on tools. According to Charles Darwin, the freeing of hands throughout the evolution of hominins allowed humans to construct stone tools and this served as an important selective pressure driving bipedal locomotion. Secondly, although humans are comparatively slower than other mammals, upright walking is the most economic form of locomotion in terms of energy expenditure compared to quadrupedal movement. Darwin’s view that bipedalism was an important first derived feature among the hominin lineage is supported by the observation of the earliest hominins, i...