There are three pervading hypotheses about the emergence of modern humans. While I was reading the summaries of the three hypotheses, I began to I favor the so-called multiregional hypothesis, which states that our species evolved relatively simultaneously in several parts of the Old World. I understood the logic behind the “Eve†hypothesis, which supports the idea that our species evolved in Africa first, then moved to the rest of the world. And once I got to the multiregional article, the last of the three, I continued to believe in the hypothesis. The analogies they gave were quite descriptive, but I am not sure they were appropriate. I began to worry that I was being convinced by my own assumptions and the author’s writing rather than relying on the facts.
The logic of the multiregional hypothesis makes perfect sense to me, though I admit I am not a biologist. Many changes in species take place in tandem with other changes or events. The whole system of evolution is, in a way, self-correcting. If one species is changed, it can potentially change all of the species connected to it. It seems entirely possible to me that our ancestors could have merged genetically with one another, incorporating traces of other now-extinct species, and it seems possible to me that we could have developed as a single species in many places across the globe.
But that is where my support for the multiregional hypothesis falls apart. As is proposed in the so-called Eve hypothesis, our species started in a more condensed region in Africa and then disseminated from there. There is even mitochondrial evidence to support the Eve hypothesis, which has proven to be highly reliable. The multiregional hypothesis seems shaky to me to say that our species was spread out as far as southern Africa, northern Europe, and eastern Asia, and was still able to exchange genetic material freely enough to evolve as a single species.
Still, this does not entirely convince me that the “Eve†hypothesis is flawless. I know there is a direct lineage that could be traced from me all the way back to an accidentally-replicating protein a couple billion years ago. But just because the lineage theoretically could be traced, does not necessarily mean that it actually needs to be. I think the best we can do is estimate that lineage, which, I realize, is what the mitochondrial DNA theorists are trying to do. It just seems that our urge to narrow our lineage down to a single female, family, or community, attempts to explain something far too precisely considering how evolution operates.
I admit I am not a scientist, nor am I fully educated on the subject, but if I were to develop a hypothesis that fits my understandings of the issues, I would say that it is more of a fusion of the Eve and multiregional hypotheses. Species develop as a group, over a period of time. Individuals cannot be considered instigators or purveyors of a new species. Individuals do not evolve, as the Eve hypothesis seems to suggest. Species evolve. And species do not evolve all at once, as the multiregional hypothesis seems to suggest. Species evolve at different times and places. Random mutations occur that either support or hinder the individual and increase their likelihood of passing their genetic material to the next generation. It is an abstract process and it’s scope is outside our normal way of thinking.
List of Works Cited:
1. Haviland, William A. (2002). Cultural Anthropology (10th edition)
2. http://www.newarchaeology.com/articles/emergence.htm
3. http://www.geocities.com/palaeoanthropology/OutofAfrica.html
4. http://www.geocities.com/palaeoanthropology/Multiregional.html
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