The history of mankind has mysteries that are still unsolved and of which there are no records. How did we get here when there are almost 7.9 billion of us? The answer lies in the hands of scientists and researchers who dive into the human genome to find answers. As in the case of a study recently published in the journal Science that assures that some 930,000 years ago, only 1280 individuals prevented the extinction of mankind.
900,000 years ago mankind was in danger of becoming extinct
From that study, the scientists concluded that only about 1280 individuals were the ones who saved humanity from total extinction. They were able to obtain this result by means of FitCoal.
FitCoal consists of studying the genomic sequences of individuals today to project them into an unknown past. To perform FitCoal or fast infinitesimal time coalescence process, they analyzed the DNA of 3154 modern humans, from African and non-African populations.
930,000 years ago, a population bottleneck drastically reduced the number of individuals to only 1,280. These individuals became responsible for preserving human history over a period of more than 117,000 years.
The cause that triggered this bottleneck may have roots in an extreme climatic phenomenon. Scientists suggest that the glaciation of that time triggered drastic climatic changes, including extremely cold temperatures and prolonged droughts.
The results of the study show that the human history of that time may have had a loss of genetic diversity of almost 65.85%. It further concludes that it was the perseverance of our ancestors that saved man from extinction as a species.
The evolution of chromosomes in humans could have been influenced by the ancestral struggle for survival, including the formation of chromosome 2. While modern humans have 23 pairs of chromosomes, in contrast to other primates that have 24 pairs, the process of chromosome 2 development could have played a crucial role in our evolution and in shaping humanity as we know it today.
Many questions that for the moment do not have an answer.
The result of this study raises a number of questions;
- How did primitive humans overcome catastrophic temperature extremes.
- Where did they live and what did they use for shelter?.
- Was it natural selection of the species that accelerated the evolution of our present brain?.
There is no fossil record from that time, so it is not easy to answer these questions. What is certain is that this mass culling coincides with the long glaciation and extremely low sea water temperatures, plus a possible prolonged period of drought in Africa and Eurasia.
The study, conducted by scientists from China, Italy and the United States, leaves open a large window for exploring human history. Perhaps in time we will be able to learn more about our ancestors.