Mysterious Genetic Origins of Secluded Amazon Tribe of Brazil (Xavante)

A recent genetic study came to an unexpected conclusion about the origins of the Xavante people. Unlike other Native American peoples, the Surui, Karitiana, and Xavante share ancestry with indigenous Australasian populations from the Andaman Islands, New Guinea, and Australia. Scientists believe the relationship stems from an earlier people known as “Population Y“ in East Asia, from which both groups diverged 15,000 to 30,000 years ago, with future Australasians migrating south and the remote ancestors of the Xavante migrating northward, finding their way to the New World and the interior Amazon Basin. Suruí and Karitiana populations in the Amazon share 1–2% ancestry with indigenous populations in the Andaman Islands, New Guinea, and Australia. For the first time, scientists discovered the Y signal in groups living outside the Amazon, specifically the Xavánte, who live on the Brazilian plateau in the country’s center. Next, the researchers used software to run various scenarios that could have resulted in the current DNA dispersal. According to the researchers, the best fit scenario involves some of the earliest, if not the earliest, South American migrants carrying the Y signal. Those migrants most likely followed a coastal route before dispersing into the central plateau and Amazon around 15,000 to 8000 years ago. The data is exactly what you’d expect if that were the case. The Suru, Karitiana, and Xavante of the Amazon have a closer genetic ancestor with indigenous Australasians than any other modern population. This ancestor appears to have left no trace among other Native American groups in South, Central, or North America. This ancestor’s genetic markers do not match any known population that contributed to Native American ancestry, and the geographic pattern cannot be explained by post-Columbian European, African, or Polynesian mixing. SOURCES: CHAPTERS: 0:00 THE SETTLEMENT OF THE AMERICAS 4:00 THE XAVANTE INDIANS 8:00 ANCIENT MIGRATIONS