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The problems with these studies were so bad that Henry Gee, a member of the editorial staff for the journal, Nature, harshly described the studies as "garbage." After considering the number of sequences involved (136 mtDNA sequences), Gee calculated that the total number of potentially correct parsimonious trees is somewhere in excess of one billion.25

Geneticist Alan Templeton (Washington University) suggests that low-level mixing among early human populations may have scrambled the DNA sequences sufficiently so that the question of the origin of modern humans and a date for "Eve" can never be settled by mtDNA.22

In a letter to Science, Mark Stoneking (one of the original researchers) acknowledged that the theory of an "African Eve" has been invalidated.23

Another interesting aspect of the "molecular clock" theory is the way in which the mutation rate itself was determined.

Contrary to what many might think, the mutation rate was not initially determined by any sort of direct analysis, but by supposed phylogenic evolutionary relationships between humans and chimps

In other words, the mutation rate was calculated based on the assumption that the theory in question was already true. This is a rather circular assumption and as such all results that are based on this assumption will be consistent with this assumption - like a self-fulfilling prophecy.

Since the rate was calculated based on previous assumptions of evolutionary time, then the results will automatically "confirm" the previous assumptions.

If one truly wishes independent confirmation of a theory, then one cannot calibrate the confirmation test by the theory, or any part of the theory, that is being tested. And yet, this is exactly what was done by scientists such as Sarich, one of the pioneers of the molecular-clock idea.

Sarich began by calculating the mutation rates of various species "...whose divergence could be reliably dated from fossils." He then applied that calibration to the chimpanzee-human split, dating that split at from five to seven million years ago.

Using Sarich's mutation calibrations, Wilson and Cann applied them to their mtDNA studies, comparing "...the ratio of mitochondrial DNA divergence among humans to that between humans and chimpanzees."24 By this method, they calculated that the common ancestor of all modern humans, the "African Eve", lived about 200,000 years ago.

Obviously then, these dates, calculated from the mtDNA analysis, must match the presupposed evolutionary time scale since the calculation is based on this presupposition.

The circularity of this method is inconsistent with good scientific method and is worthless as far as independent predictive value is concerned.

The "mitochondrial clock" theory was and is basically a theory within a theory in that it has no independent predictive power outside of the theory of evolution.

It is surprising then that scientists did not catch this inherent flaw earlier. Interestingly enough though, this flaw in reasoning was not detected for many years and perhaps would have remained undetected for much longer if a more direct mutation-rate analysis had not been done