Evolution of the genus homo - Research Paper Example

The Australopithecines were the earliest known bipedal hominid species descending from the apes, the latter using all four limbs for locomotion, like the other animal species’ of today. The Australopithecines were anatomically more related to the extant apes in terms of brain size, possessed large postcanine teeth and employed mixed climbing with bipedalism for locomotion (Wood, 1992). The Homo habilis species has been supposed to succeed the Australopithecines in the evolutionary ladder followed by Homo erectus and the Homo sapiens (Wood, 1992).

Fossil discovery and characterization has created some debate about the existence of the Homo habilis species as an intermediate species between the Australopithecines and the Homo erectus, but there is a consensus that the Homo erectus was the most primitive of the species from which the present day humans evolved. There are two distinct and contrasting views for the evolutionary ladder which the modern day Homo sapiens followed. The first suggests that the present day populations were derived as a result of in situ evolution from the Homo erectus species which was dispersed worldwide from the East African continent during the Lower Pleistocene (Finlayson, 2005).

According to the other viewpoint, all present day populations of human species are the descended from a recent common ancestor who lived in East Africa 150,000 years ago and these descendants have replaced all regional populations, if they ever existed (Finlayson, 2005). The latter view is now accepted and has been labeled as the ‘Out-of-Africa-2’ viewpoint. According to its claims, the biologically superior humans that persist till now replaced all other homo species’ and their geographical spread was driven by climatic and ecological factors (Finlayson, 2005).

The recent discovery of a hominid species in Indonesia, which has been given the nomenclature Homo floresiensis, whose existence is under active debate has confounded many anthropologists with one opinion suggesting that the species may have evolved from an early migration of the Homo erectus which was dwarfed due to peculiar ecological factors in the region (Finlayson, 2005). The features which characterized the evolution of the Homo species to the present generation of humans are a larger relative brain size, larger body, a slower rate of growth and maturation of the body, bipedal mode of locomotion and smaller teeth and jaws facilitating lesser masticator effort as compared to the primitive species of Australopithecines and Paranthropines (Aiello & Wells, 2002).

Historically, the migration of the Homo erectus occurred from Africa to the Eurasian and Asian continents from which the genus spread to all geographical regions of the world. The species evolved into the primitive ‘Neanderthal’ man which was very similar to modern humans except for the larger body size and an extremely protruding mid facial anatomy (Web, undated). The Neanderthal man can be traced to 250,00 years ago which is a relatively short period as compared to the overall time span associated with the evolution of the genus.

The discovery and employment of stones, sticks as primitive tools was a cultural revolution which was not confined to the latter species as some evidence of their use in the Pliocene and the Pleistocene eras by the Australopithecines and Paranthropines also exists. Observational studies of the modern simian species in