In the course of our lives, many of us come to ask ourselves the existential questions: Who am I? Why am I here? Where do I come from? While the answers to the first two questions may come only from within ourselves or from the hand of some higher being, the last question may be answered by science – paleoanthropology to be exact. Through the study of early hominids, humanity can find some answers about where we, as a species, come from – how we evolved and how we spread from our original home in Africa. However, the traditional model for understanding the dispersal of hominids out of Africa might be overly simplistic. Archaeological evidence has come to light that muddies the waters quite a bit.
Back when the waters were clear, the model for understanding the dispersal of hominids out of Africa was fairly straightforward. Put simply, Homo erectus/ergaster evolved in East Africa around two million years ago. Due to its increased physical capabilities and its new behavioral skills, Homo erectus/ergaster was able to emigrate to other areas of the Old World. This theory made sense on several different levels. First, geographically Africa is where this new grade of hominid would have developed. Second, Homo erectus/ergaster would have the ability to travel these longer distances with their bigger body types and more developed brains. Lastly, their technology was more advanced, enabling them to utilize a wide range of resources (Lewis, Jurmain and Kilgore, 2007, p. 228).
While this model sounds straightforward enough, the Dmanisi Hominids challenged the model in some fundamental ways. Named for the place in which the fossils were unearthed, the hominids discovered at this site are unlike many other hominids previously discussed – they may not even belong to the same grade of hominid evolution as other Homo erectus/ergaster. What makes these remains so important is that they are the best preserved hominids of such an old age found anywhere outside of Africa (Lewis, Jurmain and Kilgore, 2007, p. 228). While the Dmanisi Hominids have some characteristics in common with Homo erectus/ergaster, they also share several characteristics with early Homo specimens from East Africa. Stone tools have also been recovered from Dmanisi that are much more similar to early ones found in Africa than the advanced ones associated with Homo erectus/ergaster in the Old World. This has forced researchers to question whether or not Homo erectus/ergaster was the first hominid to leave Africa or if an earlier form of Homo claimed that prize. Was it possible that a large brain, sophisticated tool culture, and robust body were not needed to disperse out of Africa (Lewis, Jurmain and Kilgore, 2007, p. 229)?
With these questions being asked, the model for understanding the dispersal of hominids out of Africa has been revised in several ways. It seems likely now that the first hominid migrants from Africa to the Old World were not Homo erectus/ergaster but an early form of Homo, similar to Homo habilis. More generally it appears that researchers in the field may have to reevaluate the status of early Homo as well as the core of the whole dispersal model, i.e. those factors that initially motivated hominids out of Africa (Lewis, Jurmain and Kilgore, 2007, p. 229).
It seems that we may not have such a clear idea of where we come from after all. But the answer is their within our grasp. We simply have to dig a little bit deeper and study a little bit longer to uncover the truth about our origins and the truth about how we came to inhabit not just one continent, but an entire planet.
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