TRENDING SCIENCE: Will we ever know exactly where humans originated?

Where we come from is a central question in figuring out what it means to be human. We all share ancestors who lived in Africa a few hundred thousand years ago. However, many gaps remain. One such major gap is the location of where Homo sapiens (modern humans) originated.According to new research published in the journal ‘Nature’, our evolutionary origins can’t be decisively traced to a single location at any single point in time. Experts from the Natural History Museum (NHM) and The Francis Crick Institute in London, together with Germany’s Max Planck Institute for the Science of Human History, carried out a review of our current understanding of human ancestry. They found that the genetic and fossil records will not reveal any one single point in time or space.

“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,” commented co-author and NHM researcher Prof. Chris Stringer in a news item. “Over the next decade, growing understanding of our complex origins should expand the geographic focus to regions previously considered peripheral to our evolution, such as Central and West Africa, the Indian subcontinent and southeast Asia.”

The research team identified 3 main phases in human history: worldwide expansion of modern humans about 40 000 to 60 000 years ago; origin of present-day human diversity in Africa between 60 000 to 300 000 years ago; and the separation of the ancestors of modern humans from archaic human groups around 300 000 to 1 million years ago.

“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,” co-author and geneticist Pontus Skoglund of The Francis Crick Institute stated in the same news item. “Such a point in time, when the majority 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.”“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,” co-author and archaeologist Eleanor Scerri from the Max Planck Institute explained in a press release. “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.”

During an interview, Skoglund was asked if we will ever trace where humans originated: “There are lots of interesting avenues of study to explore and new resources will become available to help us carry out this work. For example, more fossils will be unearthed which could shed new light. And advances in research tools, like in the field of ancient proteomics which is currently in its infancy, could help us collect genetic information from older or less well-preserved samples. There is also more to be done with statistical models, to better analyse the data we do have.”