Humanity’s Ancestors Nearly Died Out, Genetic Study Suggests

Researchers in China have found evidence suggesting that 930,000 years ago, the ancestors of modern humans suffered a massive population crash. They point to a drastic change to the climate that occurred around that time as the cause. Our ancestors remained at low numbers — fewer than 1,280 breeding individuals — during a period known as a bottleneck. It lasted for over 100,000 years before the population rebounded. “About 98.7 percent of human ancestors were lost at the beginning of the bottleneck, thus threatening our ancestors with extinction,” the scientists wrote. Their study was published on Thursday in the journal Science.

If the research holds up, it will have provocative implications. It raises the possibility that a climate-driven bottleneck helped split early humans into two evolutionary lineages — one that eventually gave rise to Neanderthals, the other to modern humans. But outside experts said they were skeptical of the novel statistical methods that the researchers used for the study. “It is a bit like inferring the size of a stone that falls into the middle of the large lake from only the ripples that arrive at the shore some minutes later,” said Stephan Schiffels, a population geneticist at Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.