A Paper (Kim-Louise Krettek et al., A 6000-year-long genomic transect from the Bogotá Altiplano reveals multiple genetic shifts in the demographic history of Colombia. Sci. Adv.11,eads6284(2025).DOI:10.1126/sciadv.ads6284) published last June, reports that they analyzed the genes of people who lived 6,000 years ago in the highlands of Colombia, close to what is now Bogotá, and found that they are unrelated to all the rest of Amerindians that live in South America and are not similar to ancient North American natives. They were completely replaced around 2,000 years ago by other groups crossing through Panama.
The authors write:
"Here, we report genome-wide data of 21 individuals from the Bogotá Altiplano in Colombia between 6000 and 500 years ago. We reveal that preceramic hunter-gatherers represent a previously unknown basal lineage that derives from the initial South American radiation. These hunter-gatherers do not carry differential affinity to ancient North American groups nor contribute genetically to ancient or present-day South American populations. By 2000 years ago, the local genetic ancestry is replaced by populations from Central America."
This is interesting: we have people living in Colombia that are not related to Ancestral North American natives. We'd expect them to be linked to North Americans if the flow of peope into South America was north-to-south across Central America via Panama. But they differ from the 12,700 year-old Anzic-1 people!
They are not related to any known ancient or modern South American natives. But, surely they would have been part of a migration that spread across South America. They were replaced by later arrivals. This shows how the lower genetic diversity in extant Native Americans reflects loss due to whole populations becoming extinct.
The study shows that we have limited knowledge about how many waves of people reached America, when the arrived and when they died out. We also lack data regarding in-depth genetic coverage of ancient and contemporary native people.
Their analysis lead the authors to state that "these results suggest the positioning of Colombia_Checua_6000BP as an outgroup to virtually most Indigenous South Americans." in fact "this group is not more closely related to subsequent ancient Colombians than to any other South American population in our dataset..." These ancient people were replaced by other groups that reached the Colombian highlands: "Overall, the performed analyses provide robust evidence for a major genetic replacement on the Altiplano between 6000 and 2000 years ago"
The paper concludes that they are quite unique and unrelated to other native groups:
"We show that the hunter-gatherer population from the Altiplano dated to around 6000 yr B.P. lack the genetic ancestry related to the Clovis-associated Anzick-1 genome and to ancient California Channel Island individuals, suggesting their affiliation to the southern Native American lineage that became the primary source of ancestry of South Americans by 9000 yr B.P. However, unlike ancient genomes from the Andes and the Southern Cone that are associated with the same wave of ancestry, the analyzed Preceramic individuals from Colombia do not share distinct affinity with any ancient or modern-day population from Central and South America studied to date. Colombia_Checua_6000BP can thus be modeled as a previously undescribed distinct lineage deriving from the radiation event that gave rise to multiple populations across South America during its initial settlement."
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