Dating of the human ape splitting by a molecular clock Skype man sex
It is true, that because of the effects of selection, the entire mt DNA tree cannot be considered to function as a linear molecular clock. In 1983, there was archeological data that was felt to be compelling showing an Asian origin of Homo sapiens.
However, this was inconsistent with our mt DNA sequence divergence calculations.
Between 1983 and now, we have obtained thousands of complete mt DNA sequences and identified many of the likely mt DNA variants that have been acted on by positive selection.
A new statistical method for estimating divergence dates of species from DNA sequence data by a molecular clock approach is developed.
This revealed that the amount of mt DNA variation that accumulated in African macrohaplogroup L was greater than that which has accrued within Eurasia macrohaplogroup N or Asian macrohaplogroup M.
Hence, we now feel that we can adjust for the potential effects of selection in creating a non-linear clock.These unique variants create nodes in the mt DNA tree at the base of regional mt DNA lineages (haplogroups).