Historical moment: mankind lived 900 thousand years ago and had a population of only 1280 people

study, Published in Science magazineIt tells us that long before the appearance of Homo sapiens, the Earth’s population nearly disappeared.

Indeed, the number of breeding individuals declined to only 1,280 individuals and did not expand until 117,000 years ago. “About 98.7% of human ancestors have been lost“,” says Haiping Li, a population geneticist at the University of the Chinese Academy of Sciences in Beijing, who co-led the study. According to him, the fossil record in Africa and Eurasia from between 950,000 and 650,000 years ago is fragmented and “The discovery of this bottleneck may explain the time gap“.

For this discovery, researchers had to develop new tools, including a methodology that allowed them to obtain details about the oldest human ancestors. Concretely, the method the researchers used enabled 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 more precisely, enabling important evolutionary events to be identified.

“We still know very little about the population dynamics of early hominid ancestors for several reasons, including methodological limitations and difficulties in obtaining ancient DNA data from ancient human specimens.“But this new technology,” explains Serena Tucci, an anthropologist at Yale University.It has shed light on the period from 800,000 to 1 million years ago – about which we still know little – in an unprecedented wayAccording to Stanley Ambrose, an anthropologist at the University of Illinois at Urbana-Champaign.

Note that about 813,000 years ago, the population started to increase again. But according to Ziqian Hao, a population geneticist at Shandong First Medical University and Shandong Academy of Medical Sciences in Jinan, and co-author of the research, it is unclear how our ancestors managed to survive and what enabled them to survive and thrive again. All we know is that this “bottleneck” has had an impact on human diversity. Ziqian Hao believes that genetic diversity has been largely lost to modern humans (including human brain size). It is estimated that up to two-thirds of genetic diversity has been lost.