On the verge of extinction

A renowned research team from several scientific institutions in China, including Hu Wangjie, Ha Zigian, Pan Y-Huan and Li Haipeng, has just published a paper in the journal Science, whose conclusions are disturbing. These scientists examined the DNA of a sample of more than 3,000 current individuals from different regions of the planet and developed a new one genetic model (FitCoal)extremely complex for those of us who are not geneticists and mathematicians to understand.

This model makes it possible to project current genetic variation into the past and estimate the size of past populations. The results of the study suggest that humanity experienced one between 813,000 and 930,000 years ago bottleneck and was reduced to just under 1,300 breeding animals. This bottleneck may be caused by the Severe weather conditions from the end of the Lower Pleistocene lasted no less than 117,000 years and would have brought the human lineage to the brink of extinction.

This conclusion leaves us with a sinking feeling in the stomach, but also a certain skepticism about the headlines created by the editor of Science magazine himself.

This conclusion leaves us a knot in the stomachbut also with some skepticism about the headlines made by the magazine’s own publisher Science Has reconciled. We know that there were several species of the genus at this time homo distributed throughout Africa and Eurasia: Homo antecessor, Homo erectus, homo ergaster, Homo floresiensis and maybe more. Given this diversity, it seems certain that, by and large, our genealogy would have had one adaptive response enough to get out of any swamp.

After reflecting on the conclusions of our colleagues’ article, we tried to bring some order to our thoughts without getting carried away by the authority of the research papers of such a prestigious journal as… Science and for such a complex model, whose understanding is within the reach of a few.

A “black hole” in human evolution

It is true that the fossil record from about a million years ago is limited. So much so that experts always confirm the existence of a real “black hole” in hominin evolution. This lack of human fossil sites could be explained by geological causes. In addition, the area previously unexplored by archaeologists and paleontologists for economic, political and social reasons is huge.

Little by little, this black hole filled with content and a number of websites from this period have already been counted in both Africa and Eurasia. For example, let’s not forget that the TD6 level of Gran Dolina cave sitein the Atapuerca Mountains (Burgos), has been dated to about 850,000 years ago, exactly within the temporal limits of this bottleneck suggested by the results of the model by Chinese scientists.

The TD6 level of the Gran Dolina cave site in Atapuerca has been dated to approximately 850,000 years ago within the temporal boundaries of this bottleneck.

The Gran Dolina site and other European sites from the same period suggest that southern Europe was inhabited by a population towards the end of the Early Pleistocene human relatively numerous and viable. There is certainly increasing evidence for the existence of hominins from this period in East Africa or China. So what do the results of the team of Chinese scientists mean? Is it just a model that could be wrong? Not necessarily.

I think the summary was prepared by the editor of the magazine Science confused us all. Media outlets around the world have published eye-catching headlines consistent with this summary and inconsistent with the reality of what may have happened 900,000 years ago.

So far, no one has managed to positively identify this mysterious population that I believe lived in the Middle East.

At this time, one of the yet-to-be-determined hominin populations may be the origin of Neanderthals, Denisovans and modern humans. So far no one has succeeded Safely identify this mysterious population who I believe lived in the Middle East. Meanwhile, other populations of various species thrived in several regions of Africa and Eurasia: Homo antecessor, Homo erectus, homo ergaster, Homo floresiensis…

How could so few survive so long?

My interpretation of the Chinese scientists’ results is that the model FitCoal only leads to this mysterious population from which modern humanity eventually emerged, along with the Neanderthals and the Denisovans.

If what I think is correct, it would not be surprising if this mysterious population arose as a result of the bottleneck that the model suggests. FitCoal. Since this is such a small population, it is normal that archaeological and paleontological excavations have not yet found any sites of this population. But there would still be a question to answer: How is it possible that such a small population could survive for more than 100,000 years?

If the bottleneck had lasted this long, the population’s chances of survival would have been close to zero.

If the bottleneck had lasted this long, the population’s chances of survival would have been close to zero. The authors of the study are fully aware of this problem and ask the same question in the last paragraph of their article Science.

Models are just that: models that don’t necessarily have to adapt to reality. The hypothesis that Sapiens, Neanderthals And Denisovans share the same common ancestor, which may have originated somewhere in Africa or Eurasia around 900,000 years ago, is widely accepted by the scientific community. The FitCoal model was certainly capable of reaching this “mysterious” population in its estimates, but it would have ignored the other populations that were thriving across much of Africa and Eurasia at the end of the Early Pleistocene.

Other human species would have been wealthy. Can readers imagine a planet where the descendants of Homo erectus live?

If this interpretation is correct, this is the original population of the lineage that ultimately led to us was hanging by a thread. If this enigmatic population had failed due to a lack of human resources, other human species would have succeeded. Can readers imagine? a planet inhabited by the descendants of Homo erectus?