2018 has been a big year in genetics. One of the more interesting findings that has been slowly emerging in recent years is, just as Eurasians tend to have genetic contributions from extinct Neanderthals and Denisovans, sub-Saharan Africans seem to have their own admixture from a different archaic population.
Aaron P. Ragsdale and Simon Gravel
Department of Human Genetics, McGill University, Montreal, QC, Canada
December 6, 2018
… we show that human evolutionary models that include archaic admixture in Africa, Asia, and Europe provide a much better description of patterns of genetic diversity across the human genome. We estimate that individuals in two African populations have 6 − 8% ancestry through admixture from an unidentified archaic population that diverged from the ancestors of modern humans 500 thousand years ago.
The two present day African populations studied are Yorubans in Nigerian and the Luhya, a Bantu tribe in Kenya. I don’t believe there is any name yet for the putative “ghost” population, nor any recognized fossils.
An archaic population is an extinct one, a ghost population is one for which we only have statistical evidence. This ancient African population was presumably archaic and ghost.
Back in April in reviewing David Reich’s book, I suggested that
Can 2018’s tsunami of DNA data on the origins of human biodiversity help explain the puzzle of why Americans tend to equate “diversity” with Africans? …
There are, of course, two contrasting kinds of genetic diversity: within races and between races. Although it sounds politically impious, the last half century of research has shown that typical sub-Saharan Africans are more genetically different from the rest of the human race than any other large racial group on Earth.