Researchers have discovered a novel model of human evolution that challenges the notion that a single African population gave rise to all humans by analyzing the genetic makeup of present-day communities in Africa and comparing it to the fossil evidence of those populations’ earliest Homo sapiens most likely descended populations. Brenna Henn, a professor of anthropology at the Genome Center at UC Davis and the study’s corresponding author, notes that although it is well acknowledged that Homo sapiens began in Africa, it is unclear how human evolution branches split and how humans dispersed across the continent. This ambiguity, according to the author, is caused by the absence of genetic information from fossil and ancient organisms as well as the fact that the fossil record doesn’t always agree with predictions made by models built using current DNA. The origin of species is changed by this new research.
Henn and Simon Gravel, co-leaders of the study, used population genome data from southern, eastern, and western Africa to test a variety of opposing theories for how evolution and migration occurred across Africa that have been published in the paleoanthropological and genetics literature. 44 contemporary Nama people from southern Africa, a Native population noted for having very high levels of genetic variation in comparison to other modern groups, were included by the scientists. These genomes have recently been sequenced. In their communities, modern people went about their daily lives between 2012 and 2015, while researchers collected saliva samples from them. This process produced genetic data. According to the scenario, two or more weakly genetically distinct Homo populations mixed for hundreds of thousands of years before the earliest early human population split that can be seen in modern populations happened 120,000 to 135,000 years ago. Still migrating between the stem groups after the population split, the stem was only loosely organized. According to the scientists, this provides a more comprehensive account of genetic variation in both individual humans and human populations than earlier theories.
Henn described the study’s findings as “something that people have never even tested before.” This makes substantial advancements in the study of anthropology. Tim Weaver, a co-author and anthropology professor at UC Davis, remarked, “Older, more complex models suggested contributions from archaic hominins, but this model indicates otherwise.” His comparative research for the subject was based on his knowledge of what early human fossils looked like. The variance in the stem populations, according to the authors’ predictions, accounts for 1-4% of the genetic divergence between modern human populations. The interpretation of the fossil record may be significantly impacted by this model. Because of migration between the branches, these numerous lineages were likely morphologically similar, which means morphologically different hominid fossils (such Homo naledi) are unlikely to represent branches that helped to evolve Homo sapiens, according to the authors. Aaron Ragsdale of the University of Wisconsin-Madison, Elizabeth Atkinson of the Baylor College of Medicine, and Eileen Hoal and Marlo Möller of Stellenbosch University in South Africa are also co-authors.
