Experts of the Natural history museum, The Francis Crick Institute, and the Max Planck Institute for the Science of Human History Jena teamed up to figure out the different meanings of ancestry in our species’ evolutionary progress.
Humans are generally fascinated by their ancestries and, therefore, by the entire human species’ ancestry.
We often see news titles like “New human ancestor discovered” or “New fossil changes everything we thought about our ancestry.” Additionally, the meanings of words like ancestry and ancestor aren’t commonly discussed in detail.
In the new paper, posted in Nature, experts analyzed the current understanding of how modern human ancestry around the globe evolved into the distant past, and which ancestors it went through during the way back in time.
Prof Chris Stringer, a co-author researcher at the Natural History Museum, said:
“Some of our ancestors will have lived in groups or populations that can be identified in the fossil record, whereas very little will be known about others. Over the next decade, growing recognition of our complex origins should expand the geographic focus of paleoanthropological fieldwork to regions previously considered peripheral to our evolution, such as Central and West Africa, the Indian subcontinent, and Southeast Asia.”
The study found three main phases in our ancestry that are surrounded by significant question marks, which will be the starting point for future research. From the worldwide expansion of modern humans between 40-60 thousand years ago and the last known contacts with archaic groups like the Denisovans or Neanderthals to an African origin of modern human diversity approximately 60-300,00 years ago, and ultimately the complex rupture of modern human ancestors from archaic human groups between 300,000 to one million years ago.
The scientists are debating that no specific point in time can currently be identified when modern human ancestry was somehow fenced by a limited birthplace and that the known patterns of the first known appearance of anatomical or behavioural traits that are many times used to define Homo sapiens fit a wide range of evolutionary explanations.
Pontus Skoglund, a co-author from The Francis Crick Institute, said:
“Contrary to what many believe, neither the genetic or fossil record have so far revealed a defined time and place for the origin of our species. Such a point in time, when most of our ancestry was found in a small geographic region and the traits we associate with our species appeared, may not have existed. For now, it would be useful to move away from the idea of a single time and place of origin.”
Eleanor Scerri of the Pan-African Evolution Research Group at the Max Planck Institute for the Science of Human History and co-author added:
“Following from this, major emerging questions concern which mechanisms drove and sustained this human patchwork, with all its diverse ancestral threads, over time and space […] Understanding the relationship between fractured habitats and shifting human niches will undoubtedly play a key role in unravelling these questions, clarifying which demographic patterns provide a best fit with the genetic and palaeoanthropological record.”
The success of current genetic analyses suggests the importance of a more comprehensive, ancient genetic record.
That will require constant tech improvements in ancient DNA (referred to as aDNA) retrieval, biomolecular screening of fragmentary fossils to discover unrecognized human material, improved searches for sedimentary aDNA, and progress in the evolutionary information from ancient proteins.