When Did the Genetic Variations That Make Us Human Emerge?
Published:22 Aug.2022 Source:University of Barcelona
A study led by the University of Barcelona has made an estimation of the time when some of the genetic variants that characterise our species emerged. The results showed two moments in which mutations accumulated: one around 40,000 years ago, associated with the growth of the Homo sapiens population and its departure from Africa, and an older one, more than 100,000 years ago, related to the time of the greatest diversity of types of Homo sapiens in Africa.
The results of the research study also show differences between evolutionary periods. Specifically, they highlight the predominance of genetic variants related to behaviour and facial structure -- key characteristics in the differentiation of our species from other human species -- more than 300,000 years ago, a date that coincides with the available fossil and archaeological evidence. The researchers also analysed variants related to the brain, the organ that can best help explain key features of the rich repertoire of behaviours associated with Homo sapiens. Specifically, they dated variants which medical studies conducted in present-day humans have linked to the volume of the cerebellum, corpus callosum and other structures, that is, certain genes related to neural development were more highly expressed at certain times.