Keith Thomas wrote:
>
> If you want a good overview of mitochondrial DNA (rather than the evidence in this particular
> finding), you'll find a simple popular presentation in Bryan Sykes' book "The Seven Daughters of
> Eve".

There is also a "simple popular presentation" of Stephen Oppenheimer's
theory of the single exit from Africa in his book, "The Real Eve, Modern
Man's Journey Out of Africa", published in paperback in North America by
Carroll & Graf in 2003 (ISBN 0-7867-1334-8).

He states there is archaeological evidence in the Levant of an earlier
exit from Africa by anatomically modern humans via the northern route,
ie, the Sinai area, between 90,000 to 120,000 years ago but those people
did not survive probably due to extreme climatic change at 90K years BP.
  His view is that the mtDNA evidence supports the single exit from
Ethiopia 50,000 years later.

Barb