With the New Bantu Expansion gearing up to be perhaps the most important global event of the 21st Century, it’s worth looking at the cost paid by Pygmies and other diverse groups during the Old Bantu Expansion of prehistory.
Svante Paabo’s breakthrough in being able to sequence DNA from ancient skeletons drove much of the most interesting science of the decade now just closed. But, we’ve tended to be lacking in ancient DNA from sub-Saharan Africa because DNA breaks down faster in warm and wet climates. A variety of other evidence has been pointing towards some interesting weirdnesses in current sub-Saharan DNA, such as indications of a lost “ghost archaic” ancestral population. I wrote about the “The Ghosts of Africa” two years ago in Taki’s Magazine in my third review of geneticist David Reich’s Who We Are and How We Got Here.
Reich has now published on the Old, Weird Africa. From Nature:
Ancient West African foragers in the context of African population history
Mark Lipson, Isabelle Ribot, […]David Reich
Nature (2020), Published: 22 January 2020Our knowledge of ancient human population structure in sub-Saharan Africa, particularly prior to the advent of food production, remains limited. Here we report genome-wide DNA data from four children—two of whom were buried approximately 8,000 years ago and two 3,000 years ago—from Shum Laka (Cameroon), one of the earliest known archaeological sites within the probable homeland of the Bantu language group1,2,3,4,5,6,7,8,9,10,11. One individual carried the deeply divergent Y chromosome haplogroup A00, which today is found almost exclusively in the same region12,13. However, the genome-wide ancestry profiles of all four individuals are most similar to those of present-day hunter-gatherers from western Central Africa, which implies that populations in western Cameroon today—as well as speakers of Bantu languages from across the continent—are not descended substantially from the population represented by these four people. We infer an Africa-wide phylogeny that features widespread admixture and three prominent radiations, including one that gave rise to at least four major lineages deep in the history of modern humans.
From Science:
DNA from child burials reveals ‘profoundly different’ human landscape in ancient Africa
By Ann GibbonsJan. 22, 2020 , 1:00 PMCentral Africa is too hot and humid for ancient DNA to survive—or so researchers thought. But now the bones of four children buried thousands of years ago in a rock shelter in the grasslands of Cameroon have yielded enough DNA for scientists to analyze. It’s the first ancient DNA from humans in the region, and as the team reports today in Nature, it holds multiple surprises. For one, the area today is the homeland of Bantu speakers, the majority group in western and Central Africa.
As the world enters the age of the New Bantu Expansion, more attention should be paid to the history of the Old Bantu Expansion. Bantus are the primary ancestors of African-Americans. They expanded out of a homeland near the Nigerian-Cameroon border with the aid of two major technological advances: agriculture and iron-making. They wrested sub-Saharan Africa away from other racial groups.
But the children turned out to be most closely related to hunter-gatherers such as the Baka and Aka—groups traditionally known as “pygmies”—who today live at least 500 kilometers away in the rainforests of western Central Africa.
In other words, the Pygmies were marginalized by the Bantu Expansion.
“In the supposed cradle of Bantu languages and, therefore, Bantu people, these people are basically ‘pygmy’ hunter-gatherers,” says Lluís Quintana-Murci, a population geneticist at the Pasteur Institute and CNRS, the French national research agency, who was not part of the new study. He and others have long suspected that these groups had a larger range before the Bantu population exploded 3000 years ago. The second big surprise came when the team compared the children’s DNA to other genetic data from Africa and found hints that the Baka, Aka, and other Central African hunter-gatherers belong to one of the most ancient lineages of modern humans, with roots going back 250,000 years.
In the new study, geneticists and archaeologists took samples from the DNA-rich inner ear bones of the four children, who were buried 3000 and 8000 years ago at the famous archaeological site of Shum Laka. … Comparing the sequences to those of living Africans, they found that the four children were distant cousins, and that all had inherited about one-third of their DNA from ancestors most closely related to the hunter-gatherers of western Central Africa. Another two-thirds of children’s DNA came from an ancient “basal” source in West Africa, including some from a “long lost ghost population of modern humans that we didn’t know about before,” says population geneticist David Reich of Harvard University, leader of the study.
The discovery underscores the diversity of African groups that inhabited the continent before the Bantus began to herd livestock in the grassy highlands of western Central Africa.
We often hear Africans saluted for their genetic diversity, but the ironic reality is that the Old Bantu Expansion was one of the great disasters for human genetic diversity.
The Bantus made pottery and forged iron, and their burgeoning populations rapidly displaced hunter-gatherers across Africa. Analyzing DNA from a time before this expansion offers “a glimpse of a human landscape that is profoundly different than today,” Reich says.
… The team’s bold new model pushes back Central African hunter-gatherer origins to 200,000 to 250,000 years ago—not long after our species evolved. The model suggests their lineage split from three other modern human lineages: one leading to the Khoisan hunter-gatherers in southern Africa, one to east Africans, and one to a now-extinct “ghost” population. …
Remember how I’ve been pointing out for years that New York Times reporters have developed an upside-down style in which they make the beginning of their articles on potentially politically incorrect topics as boring as possible and only slip in the interesting bits toward the end, long after most NYT subscribers have moved on, reassured that reality is as uninteresting as they assumed? Well, NYT genetics reporter Carl Zimmer’s write up, “Ancient DNA from West Africa Adds to Picture of Humans’ Rise,” is a classic in this regard. The word “pygmy” doesn’t appear until the 18th paragraph and the word “ghost” not until the 24th paragraph.
