Four ancient youngsters, one pair from around 8,000 years ago and another from about 3,000 years ago, have opened a window on humankind’s far older, far-flung African origins.
Analyses of the west-central African children’s DNA indicate that at least three major human lineages —ancestral to either today’s central African hunter-gatherers, southern African hunter-gatherers or all other present-day people — genetically diverged from each other in rapid succession between roughly 250,000 and 200,000 years ago.
A fourth, previously unknown human population also emerged in that time span and left a small genetic mark on modern western and eastern Africans, a team led by evolutionary geneticists Mark Lipson and David Reich, both of Harvard Medical School, reports online January 22 in Nature. That human line possessed a small amount of DNA from hominid populations that had originated before the rise of the human species, possibly Neandertals.
“This quadruple radiation [of human lineages] had not been identified before from DNA,” Reich says.
That genetic evidence from the long-dead kids fits a scenario in which different Homo sapiens populations emerged in different parts of Africa as early as around 300,000 years ago, followed by a mixing and mingling of populations across the continent (SN: 9/28/17).
