Sep 19, 2023
Our long-ago human ancestors nearly vanished from the planet. They dropped to as few as 1,280 reproducing individuals, a new study has found. And their numbers remained that low for as many as 117,000 years.
That means 98.7% of human beings were lost during this period. It was roughly 900,000 years ago, the study found. Scientists said this period overlaps with a gap in human fossils being discovered. All of this could mean a new hominin species formed. And it may have been a common ancestor of modern humans, or Homo sapiens and Neanderthals, the study said.
The study involved a new analysis of human DNA. Scientists looked at 3,154 present-day human genomes. Researchers were based in China, Italy, and the US. They used a new computer model for the analysis. The study was published in the journal Science on August 31.
Nick Ashton works for the British Museum. And Chris Stringer works for the Natural History Museum in London. The pair are researchers of human evolution. They were not involved in the study. But they said that the study shows how vulnerable early human groups were.
The so-called population “bottleneck” lines up with major climate changes on Earth. This climate event was known as the mid-Pleistocene transition. Glacial periods became longer and more intense. Severe drops in temperature occurred. The weather was also extremely dry.
Human populations began rising again some time later. This happened as the climate shifted back to less extreme conditions. Humans also discovered fire during this period. It was roughly 813,000 years ago, researchers said.
Photo from Unsplash courtesy of Eugene Zhyvchik.
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