Origin
& Migration of modern humans:
the "Out of Africa" hypothesis
Family tree of 53
individual humans, based
on a phylogenetic analysis of the complete (16,587bp) mitochondrial DNA
(mtDNA) genome (Ingman
et al. 2000). It must
be emphasized that the tree shows individuals,
who are not necessarily representative of the group with which
they
are identified.
Four major groups are identified: three of these
(shown
in purple) are composed
exclusively
of African individuals, which is consistent with the African theory
of human origins, since the oldest human group is expected to have
the greatest genetic diversity. The fourth group (indicated by the *)
consists of three sub-groups, one African (in green)
and the other two (in red and blue)
comprising various Eurasian, Asian, New World, and Australian
individuals. Europeans fall entirely in the blue group
(Haplogroup M).
The common origin of the latter groups is consistent with the
"Out
of Africa" hypothesis, that all Australian,
East
Asian, Central Asian,
European, and
New
World peoples have come from a relatively small group that
expanded outward from Africa about 40,000 years ago.
