Out of Africa, Homo Sapien, and the Mitochondrial Eve

Quite a debate has taken place in the scientific community lately between supporters of the "Out of Africa" theory of evolution versus proponents of the multiregional theory of human evolution. With each new scientific discovery or study, a slew of papers and reports are written to defend a point of view or attack the standards of the other.

The key ammunition for those entrenched on the "Africa" side is the famous study done by Wilson, Cann, and Stoikberg in 1987. It this study, researchers compared the mitochondrial DNA (mtDNA) of various peoples across the globe. What they found is that the peoples of New Guinea, Europe, Asia, and Australia were all more closely related than the peoples of Africa. Furthermore, the variation among the African human beings was greater than the variation among Europeans. This led on the conclusion that the genes of those living indigenously in Africa have had more generations to mutate and undergo small mitochondrial changes. When they considered the rates of mutation for mtDNA and pinpointed a date for the very first humans that spawned all other humans living across the globe today, they arrived at approximately 200,000 years ago. This is what gave rise to the related, yet controversial "Mitochondrial Eve" theory.

Granted, the core idea behind "Mitochondrial Eve" (that in essence all life of a species must have, at some point in its past, a common ancestor) is a basic mathematic fact. The gray area comes when determining a date for her existence. Did the human species as we know it today evolve in many different locations after Homo erectus spread around the globe? Or did modern man evolve in Africa and spread around the world, wiping out the previous wave of habitats? A study done in 2000 by a Swedish research group appears to reinforce the "recent African origin" idea.

After studying nearly the complete mtDNA sequence in 53 diverse individuals (previous teams looked at only approx. seven percent of the sequence), the University of Uppsala group deduced that humans evolved from a core group in Africa 170,000 years ago that colonized the rest of the world around 50,000 years ago.

However, there remain several validity issues in any such study. One common question concerns the assumptions made by the researchers. Many scientists point out that in the last few years it has become known that mtDNA can be passed on through male lineages. Previously, and in any such "Mitochondrial Eve" research, it had been assumed that mtDNA was strictly passed through females. In addition to that, several skeptics have observed problems with the methods they used in evaluating the rates of change within segments of mtDNA. Yet another possible problem with the experiments is the relatively small sample group. Fifty three people out of the six billion that are alive on Earth today is a ridiculously small percentage of the Earth's population. It is quite realistic that that the researchers completely missed large pockets of multiregional evolved humans.

But what evidence is there supporting a multiregional theory? Some proponents, such as Alan Thorne and Milford Walpoff, point to common morphology among ancient human fossils from China, Australia, and Java when compared to today. They claim that if there existed a Homo sapien colonization that took place around 50,000 years ago, there would not be as many similarities in modern man to fossils dated at least 10,000 years before the wave came from Africa. Essentially, advocates of the multiregional theory claim that the fossil record is on their side.

Either way, this is a battle that will more than likely rage on for quite some time among scientists. Even though the idea that a "Mitochondrial Eve" lived just 200,000 years ago is falling out of favor with most evolutionary scientists and microbiological researchers, there is still much to be said for the "Out of Africa" theory. Likewise, in the future more and more fuel will be given to the multiregionalists. However, until the "Out of Africa" crowd develops a more stable genetic approach or can come up with more solid evidence, the multiregional theory must be considered, if not accepted.

In conclusion, there are some alternate issues that this scientific endeavor must deal with in terms of naming. When using names like "Eve" to describe something concerning the rise of mankind, it is obviously an allusion to the creation legend of Christianity. Of course, the popular media will use this, as Newsweek did in 1988, to make a connection between religion dogma and science to the general public, which is just about the last thing the scientific community wants or needs. Furthermore, using the term "Out of Africa," although descriptive, is a dangerous notion. First, "Out of Africa" happened to be a popular Academy Award winning movie released just two years before the theory came to light, again connecting popular media to the scientific body. Also, for many people in the current modern world, hearing the words "Out of Africa" invokes, unconsciously or consciously, thoughts of slave trading and racism. This is not to say that there are issues of sympathy or racial hatred involved in the current debate, but it is instead suggesting that the terminology stirs up such feelings and the possibility exists. Therefore, it is suggested that there should be a change of terminology, because there is no room for personal emotions when doing true logical study. There are enough pitfalls in the search for man's true origins already. Researchers do not need another one by public perception of the study being turned into something it is not.