Michael Cremo - Human Devolution - A Vedic Alternative To Darwin's Theory

The presence of mitochondria in eukaryotic cells is a bit of a mystery. In eukaryotic cells, the DNA is found on chromosomes isolated in the cell’s nucleus. In prokaryotic cells, there is no nucleus and the DNA molecules simply float in the cell’s cytoplasm. Almost all of the plants and animals living today are either single eukaryotic cells or are composed of many eukaryotic cells. Only bacteria and blue-green algae are prokaryotic. Evolutionists theorize that the mitochondria in today’s cells are remnants of prokaryotic cells that invaded primitive eukaryotic cells. If that were true, then this most probably happened very early in the evolutionary process, when only single celled creatures existed. This implies that the mitochondria in all living things should be quite similar. But the mitochondrial DNA in mammals “cannot generally be classified as either prokaryote-like or eukaryote-like.” Furthermore: “The mammalian mt [ mitochondrial ] genetic code is different from the so-called universal genetic code . . . mammalian mitochondria are very different from other mitochondria. In yeast mitochondria, for example, not only is there a slightly different genetic code, but also the genes are widely spaced and in a different order, and in some cases they contain intervening sequences. These radical differences make it difficult to draw conclusions regarding mitochondrial evolution” (Anderson et al. 1981, p. 464). In other words, the presence of the various kinds of mitochondria in different creatures argues against an evolutionary origin.

But let us now return to the main point. In mammals, the mitochondria in the mother’s egg have their own DNA. This mitochondrial DNA does not, however, combine with the DNA from the father. Therefore, all of us have in our cells mitochondria with DNA that came only from our mothers. The mitochondrial DNA in our mothers came from their mothers, and so on back into time. The African Eve researchers assume that the only changes in the mitochondrial DNA are the changes that accumulate by random mutations. By studying the rate of mutation, scientists believe they can use mitochondrial DNA as a kind of clock, relating numbers of mutations to numbers of years. And by looking at the mitochondrial DNA in different human populations in various parts of the world, scientists believe they can sort out which group is the parent group for the others.

They believe that the parent group, which must also be the oldest group, can be identified by computer programs that sort the population groups into branching tree patterns. Out of the many statistical trees that can be generated, the shortest one, the one with the least number of branchings, is called the “maximum parsimony tree,” and researchers believe it to be identical to the actual historical relationships of the various population groups in the tree. The branch (“clade”) forming the base of the tree (the “basal clade”) is supposed to be the parent group. According to evolutionary theory, it should, in addition to being at the base of the tree, have the most variation (i.e. the most mutations) in its mitochondrial DNA, relative to the other population groups. So in this way, researchers believe they can find where and when the root population existed. But some scientists say that the clock is not very accurate and that the genetic information contained in the mitochondrial DNA in today’s populations is not sufficient to tell us with certainty the geographical location of the first human population.

In one of the original African Eve reports (Cann et al. 1987), researchers analyzed the mitochondrial DNA from groups of modern humans from different regions throughout the world. They analyzed the sequence of nucleotide bases found in a particular section of the mitochondrial DNA in all of the individuals being studied. They then used a computer program to arrange the various kinds of mitochondrial DNA sequences (called haplotypes) into a tree. According to the report, the root (or basal clade) of the maximum parismony tree of haplotypes was the African group. But Templeton (1993, p. 52) pointed out that Maddison (1991) had rerun the data and found ten thousand trees that were shorter (i.e. more parsimonious) than the “maximum parsimony tree” reported by the African Eve researchers. Many of these trees had mixed African/Asian roots. Analyzing another “African Eve” report (Vigilant et al. 1991), Templeton (1992) found 1,000 trees two steps shorter than the one put forward by those researchers, who had claimed it was a “maximum parsimony” tree.All of the thousand more parsimonious trees found by Templeton in his 1992 study had non-African basal clades (Templeton 1993, p. 53). This would be consistent with accounts found in the ancient Sanskrit writings of India, which would place the original human populations on this planet in the region between the Himalayas and the Caspian Sea.

Why such different results? Templeton (1993, p. 52), considering another African Eve report, explained: “Computer programs . . . cannot guarantee that the maximum parsimony tree will be found when dealing with such large data sets as these because the state space is too large to search exhaustively. For example, for the 147 haplotypes in Stoneking, Bhatia, and Wilson (1986), there are 1.68 x 10294 possible trees. Finding the maximum parsimony set among these many possibilities is nontrivial.” The computer programs tend to pick out a tree that is maximally parsimonious only in relation to a subset of the total number of possible trees. Which subset of trees that is selected depends on the order in which data are fed into the computer. To guard against this problem, it is necessary to randomize the sequence in which the data are entered over a series of runs. When one has done this a sufficient number of times, so as to find the maximum parsimony trees for various local subsets of the data, then one can compare these trees and arrive at a conclusion. This was not done in the original African Eve studies (the computer program was run only once), and thus the conclusions are not reliable. Also, even data randomization techniques do not completely solve the problem (Templeton

1993, p. 53). So this means that it really is not possible to conclusively determine the common geographical origin of dispersed human populations from the genetic data available today.

In addition to presenting inaccurate conclusions about maximum parsimony trees with African basal clades, the African Eve researchers (Cann et al. 1987; Vigilant et al. 1991) also made misleading statements about the level of mitochondrial DNA diversity in various populations. The African Eve researchers assumed that mutations occur at some fixed rate, and therefore the population with the most internal diversity, relative to the others, should be the oldest. Because the African populations had a higher level of internal diversity than Asian and European populations, the researchers claimed that the African populations were the oldest. But Templeton (1993, p. 56) noted that “no statistical test is presented in either paper in support of this claim.” He pointed out that when proper statistical methods are applied, there is no significant degree of diversity in the mitochondrial DNA of Africans, Europeans, and Asians (Templeton 1993, p. 57). As Templeton himself put it: “The apparent greater diversity of Africans is an artifact of not using sufficient statistics for making inference about the . . .process that led to the present-day human populations. In summary, the evidence for geographical origin is ambiguous. . . . there is no statistically significant support for an African origin with any mtDNA data” (Templeton 1993, p. 57).

Now let us consider the ages for the antiquity of anatomically modern humans proposed by the original African Eve theorists. They tried to calculate the time it took for the observed mtDNA diversity in today’s human populations to accumulate, based on rates of mutation. This time is called “the time to coalescence,” the time at which all the mtDNA sequence diversity in present human populations coalesces into a single past mtDNA sequence, the source of the present diversity. One group of researchers (Stoneking et al. 1986) got an age of 200,000 years for Eve, within a range of 140,000 to 290,000 years, using intraspecific calculations for the molecular clock. Intraspecific means that they based calculations on rates of mutations in human populations only. Another group (Vigilant et al. 1991), using interspecific calculations, also got an age of 200,000 years for Eve, but with a range of 166,000 to 249,000 years. Interspecific means they based their calculations on assumptions about the time at which the human line separated from the chimpanzee line.