Tracing Ancestry with MtDNA - Nova
By Rick Groleau
In 1987, three scientists announced in the journal
Nature that they had found a common ancestor to
us all, a woman who lived in Africa 200,000 years
ago. She was given the name "Eve," which was
great for capturing attention, though somewhat
misleading, as the name at once brought to mind
the biblical Eve, and with it the mistaken notion
that the ancestor was the first of our species -- the
woman from whom all humankind descended.
The "Eve" in question was actually the most recent
common ancestor through matrilineal descent of all
humans living today. That is, all people alive today
can trace some of their genetic heritage through
their mothers back to this one woman. The scientists
hypothesized this ancient woman's existence by
looking within the cells of living people and analyzing
short loops of genetic code known as mitochondrial
DNA, or mtDNA for short. In recent years, scientists
have used mtDNA to trace the evolution and migration
of human species, including when the common ancestor
to modern humans and Neanderthals lived -- though
there has been considerable debate over the validity
and value of the findings.
http://www.pbs.org/wgbh/nova/neanderthals/mtdna.html
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