Genetic analysis of 328 ancient individuals reveals a previously unrecognized Indigenous lineage in Argentina’s Pampas that goes back at least 8,500 years. First identified in remains from Jesús María, this ancestry remained remarkably stable for millennia despite cultural change and limited trade. The lineage contributes significantly to the ancestry of many modern Argentinians, and the findings caution against assuming that language diversity always reflects deep genetic differences.
Ancient DNA Reveals a Lost 8,500-Year-Old Lineage Dominant in Argentina’s Pampas
Genetic analysis of 328 ancient individuals reveals a previously unrecognized Indigenous lineage in Argentina’s Pampas that goes back at least 8,500 years. First identified in remains from Jesús María, this ancestry remained remarkably stable for millennia despite cultural change and limited trade. The lineage contributes significantly to the ancestry of many modern Argentinians, and the findings caution against assuming that language diversity always reflects deep genetic differences.
11:31 AM, 11/21/2025Science
Researchers analyzing ancient DNA have identified a previously unrecognized Indigenous lineage in Argentina’s Pampas that dates back at least 8,500 years and remained regionally dominant for millennia.
By sequencing DNA from the skeletal remains of 328 individuals spanning roughly 10,000 years, the team traced a continuous genetic signal first seen in remains excavated near Jesús María. Successive, younger samples show remarkably little change in this ancestry component despite repeated environmental stresses, cultural shifts and occasional contact with neighboring groups.
Key findings
Archaeological evidence indicates a rise in population density in the Pampas around 3,500 years ago, a change that may coincide with the spread of the bow and arrow. Still, material signs of exchange—carving stones and copper beads among them—are sparse, and the genomic data indicate limited gene flow into this central-Argentinian lineage.
When people in the Pampas began cultivating crops about 1,500 years ago, their genetic profile remained largely unchanged. That contrasts with many parts of Africa, Europe and Asia, where the spread of farming was often accompanied by large-scale migration and replacement of local genomes. The researchers interpret this as evidence that Pampas communities adopted new technologies and cultural practices while largely maintaining their ancestral gene pool.
“[Our findings suggest] that the ancestry component represented by [the Jesús María individual] is the main Native American lineage in the region up to the present day,” the authors write in the study published in Nature.
Modern genetic surveys show that many Argentinians retain ancestry derived from this Pampas lineage. Although intermarriage and admixture with neighboring Indigenous groups did occur, the lineage’s genetic continuity endured through pre-Columbian times, the arrival of Europeans and into the last millennium.
The study also highlights an important caveat: linguistic diversity recorded in the region by the sixteenth century does not necessarily map onto deep genetic divisions. Languages can change or spread through cultural contact independent of major shifts in ancestry, and the Pampas case provides a clear example of cultural and linguistic diversity coexisting with long-term genetic continuity.
Why it matters
This research reshapes our understanding of South American population history by documenting a long-lived, locally persistent lineage in a region once thought to have experienced substantial movement and replacement. It underscores the complexity of human prehistory: genetic stability, cultural change, and episodic contact can all shape regional identity in different ways.