An Exemplary Biologist

The BBC reports that a paper published in the American Journal of Human Genetics concludes that the human population nearly speciated (my term) due to prolonged separation lasting 100,000 years, and occurring 150,000 years ago. Dr Spencer Wells, director of the Genographic Project, said that the African groups were isolated for a very long time as shown by differences in their mitochodrial DNA, which is genetic material inherited only from females. This gives a maternal history of a group. From this basis, scenarios have been hatched concerning the migratory patterns of each group. And from this, speculations as to why they split as well as how and where.

However, a rational voice is included in the mix: that of Dr. Sarah Tishkoff, of the University of Pennsylvania, who said,

"Although there is very deep divergence in the mitochondrial lineages, that can be different from inferring when the populations diverged from one another."

The sentiment that wild extrapolations might not be true is unusual in the biological race to publish. Inferences drawn on the flimsiest of premises can be and are published at the drop of a hat. It is not de riguer to call them what they are, as Dr. Tishkoff did: inferences.

So my hat is off to Dr Tishkoff. May her example be followed and multiplied.