A 1987 paper in the prestigious
journal Nature reported that “all mitochondrial DNA stems from one woman” and
that she had lived in Africa some 200,000 years ago. The paper, authored by
Rebecca L. Cann, Mark Stoneking, and their doctoral advisor, Allan Wilson, at
the University of California, Berkeley, aroused intense interest and
controversy for many reasons, and it continues to do so.
The authors referred to the samples
they analyzed as “mitochondrial DNA,” whereas the press dubbed them
“mitochondrial Eve”—far more memorable, but also subject to misinterpretation.
This Eve was not the single and only woman living at the time, as was said of
the Eve of Genesis. In addition, the literal Biblical interpretation computed
the age of humans to a time measured in thousands of years, not 200,000 years.
Moreover, many evolutionists believed that humans evolved in separate parts of
the world at about the same time, rather than the “Out of Africa” theory, in
which Anatomically Modern Humans originated in Africa and then migrated
worldwide.
Adam and Eve, completed after 1536 by the German Renaissance painter Lucas Cranach the Younger (1515–1586). |
Cann and her colleagues analyzed
mitochondrial DNA (mtDNA) and not nuclear DNA (nDNA), the latter responsible
for transmitting the color of our eyes, racial characteristics, and
susceptibility of certain diseases; mtDNA only codes for manufacturing proteins
and performing other mitochondrial functions. Present in all cells of our body,
nDNA is a merger of our mother’s and father’s DNA (recombination), whereas
mtDNA is derived virtually exclusively from the maternal side with few if any
mtDNA contributed from the sperm. Closely related individuals have almost
identical mtDNA, with occasional mutations arising over thousands of years. It
is assumed that the fewer the number of mutations, the shorter the period of
time since common ancestors diverged.
Proponents of mitochondrial Eve do
not suggest that this Eve was the first woman or only woman living at the time.
Rather they estimate that some catastrophic event occurred, dramatically
reducing Earth’s population to some 10,000–20,000, and that only this Eve had
an unbroken line of female descendants. Eve was said to be the most recent
common ancestor from whom all living humans descended.
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