Reading the history of indigenous South American peoples in ancient DNA

Ancient human DNA dating back almost 9,000 years has provided significant genetic insights for an international large-scale study in South America.

Our researchers, as part of an international team, analysed the ancient DNA from 89 humans who lived in South America between 500 and 9,000 years ago, and compared it with the genetic diversity of present day occupants, to shed light on the genetic changes over time.

Extracted from skeletons and mummies, ancient DNA provides a genetic snapshot of past individuals. Comparing the genetic makeup of populations across time and space, it can reveal the hidden stories of populations, including expansions and reductions, migrations, replacements, mixing, and more. 

Associate Professor Bastien Llamas, who has been studying ancient DNA within South America for more than 10 years, says that the recent study has expanded previous knowledge, providing evidence for an early and dynamic settlement of the Andean Highlands.

“In collaboration with many scientists from the Central Andes area and international institutions, our research showed that highland populations split from coastal populations as early as 9,000 years ago, before developing a north-south structure by 5,800 years ago—we can still observe these patterns in present days!”

“Archeological research shows that the central Andes region is extremely rich in cultural heritage, however up until now the genomic makeup of the region before arrival of Europeans has never been studied. Our research helped to uncover that great pre-Inca civilisations such as Moche, Wari and Nasca seemingly established their cultural domination without moving armies and replacing populations.” 

When Europeans arrived, they discovered a massive Incan empire that covered thousands of kilometres from Ecuador through to northern Chile. The results show close genetic relationships between individuals at the extreme edges of the empire, suggesting long-range mobility.

“Ancient DNA is fascinating because it literally connects past and present people,” said Associate Professor Llamas.

It is hoped this more detailed genetic picture of populations of the central Andean Highlands will allow archeologists to ask new questions about the history of the region and will lead to further cultural learnings and strengthen collaboration with local communities still living in the region.