when human ancestors nearly went extinct

When the pre-human population dropped to about 1,000 individuals 900,000 years ago.

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To make their discovery, the researchers needed to invent new tools. Advances in genome sequencing have improved scientists’ understanding of population sizes for the period after modern humans emerged, but the researchers developed a methodology that enabled them to fill in details about earlier human ancestors. Serena Tucci, an anthropologist at Yale University in New Haven, Connecticut, says that such work was sorely needed. “We still know very little about the population dynamics of early human ancestors for several reasons, including methodological limitations and difficulties in obtaining ancient DNA data from old Homo specimens,” she says.

The researchers’ method allowed them to reconstruct ancient population dynamics on the basis of genetic data from present-day humans. By constructing a complex family tree of genes, the team was able to examine the finer branches of the tree with greater precision, identifying significant evolutionary events.

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