All life on Earth shaped natural selection. Adaptable creatures have a higher chance of reproducing when the world around them changes. Humans are no exception, and while we know of a few recent examples of evolution, we do not know much about how natural selection shapes the human genome. The findings, which published in the journal Nature Human Behavior, represent a modest step towards a deeper understanding of human evolution.
The goal of the study’s authors was to figure out how natural selection of complicated features worked. The researchers examined 870 human features that are influenced many genes and discovered that 755 of them had transformed by natural selection in the previous 2,000 to 3,000 years.
Weichen Song, a Shanghai Jiao Tong University professor, headed the team. The researchers utilized data from the UK Biobank and the Psychiatric Genomics Consortium to study current human genetics.
They matched this information to ancient genetic DNA from Europe and the Near East, which revealed alterations in the human genome over the previous 45,000 years.
The team’s most surprising discovery was that skin pigmentation, body measurement, and nutritional features were “constantly under severe selection pressure” during the times studied.
The balancing task of preventing UV damage, vital vitamin D requirements, and heat control puts pressure on skin color. In reality, the Cheddar Man, one of the first Britons, had dark skin.
Genetic influences, as well as environmental forces such as ecology, climate, and migration, have influenced body measurements and nutritional characteristics. The researchers also discovered that some illnesses have not been faded out as well as one might assume. Although the hereditary variables linked to anorexia nervosa and inflammatory bowel diseases reduced, instances continued to arise.
While the findings are exciting, the team sees them as only a basic foundational step in the direction of future in-depth research. The use of genomes from the United Kingdom, which mostly contained persons of European descent, constrained the study. It further hampered by the use of ancient genomes.
The approach of genome-wide association studies, which does not discriminate between association and causation, further limits the effort. The Human Genome Project completed in 2003, therefore a thorough examination of the human genome is just 20 years old – there are still many mysteries to solve in it, as well as how evolutionary processes have influenced it.
