Figure. Schematic diagram of human population size history.

With the support from the National Natural Science Foundation of China (grants 32270674 and 91131010), Dr. Haipeng Li, a theoretical population geneticist and computational biologist at Shanghai Institute of Nutrition and Health, Chinese Academy of Sciences, and Dr. Yi-Hsuan Pan, an evolutionary and functional genomics expert at East China Normal University, developed a new genomic method and inferred the population size of ancient humans. They revealed a severe bottleneck in the human population which almost wiped out the chance for humanity as we know today. The study was published as a research article entitled “Genomic inference of a severe human bottleneck during the Early to Middle Pleistocene transition” in Science on September 1, 2023 (https://www.science.org/doi/10.1126/science.abq7487)

The researchers first developed a new method namely the fast infinitesimal time coalescent process (FitCoal), and then they were able to accurately determine demographic inferences by using modern-day human genomic sequences from 3,154 individuals. Their findings indicate that early human ancestors went through a prolonged, severe bottleneck in which approximately 1,280 breeding individuals were able to sustain a population for about 117,000 years. This bottleneck can explain the gap in the African fossil record because the gap coincides with this proposed time period of significant loss of life.

There is reason to believe an ancestral struggle occurred between 930,000 and 813,000 years ago. Our ancestors should have formed a community with a shared future of mankind because they were united to fight against climate changes.

Fabio Di Vincenzo (a paleoanthropologist at University of Florence), Giorgio Manzi (a paleoanthropologist at Sapienza University of Rome), and Yun-Xin Fu (a theoretical population geneticist at University of Texas Health Science Center at Houston) co-authored this study.