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Sections of the following text are taken from the official National Geographic press release.
Ancestry may date to Altiplano’s initial settlement
New genetic research led by the Genographic Project team shows a distinctive ancestry for the Uros populations of Peru and Bolivia that predates the arrival of the Spanish conquistadores and may date back to the earliest settlement of the Altiplano of the central Andes some 3,700 years ago.
Despite the fact that the Uros today share many lineages with the surrounding Andean populations, they have maintained their own divergent genetic ancestry.
“The timing of human settlement in the Andean Altiplano is one of the great mysteries of our species’ worldwide odyssey — a vast, high-altitude plain that seems utterly inhospitable, yet it has apparently nurtured a complex culture for millennia,” said Spencer Wells, Genographic Project director and National Geographic Explorer-in-Residence.
This significant new study reflects the importance of the Genographic team’s careful, patient work with the members of the indigenous communities living in this remote corner of the mountainous South American terrain, and sheds light on how our species has adapted to disparate ecosystems since its relatively recent exodus from an African homeland less than 70,000 years ago.”
Who are the Uros?
The Uros are a self-identified ethnic group, about 2,000 of whom live in Peru, many of them on artificial floating islands on Lake Titicaca. Another 2,600 individuals live beside lakes and rivers of Bolivia.
According to some anthropologists, the Uros are descendants of the first settlers of the Altiplano — the Andean plateau — yet their origin has been subjected to considerable academic debate. Those from Peru have long claimed to descend from the ancient Urus (Uruquilla speakers), using their differentiated ethnic identity to assert rights and prerogatives for their use of Titicaca’s natural resources.
The Uros have historically been the target of discrimination by the pre-Inca, Inca and the Spanish, and this continues today. Some people have alleged that the Uros disappeared a long time ago and that the new islanders have conjured up an ancient heritage in order to attract tourists and receive special recognition and rights.
Unveiling an ancient connection through DNA
Representatives of the Genographic Project, which uses advanced, multi-locus DNA analyses to help answer fundamental questions about human origins, collaborated with 388 indigenous people from Peru and Bolivia, including Peru’s Los Uros community and Bolivia’s Uru-Chipaya and Uru-Poopó communities, swabbing their cheeks to collect DNA samples.
Researchers then analyzed Y-chromosome and mitochondrial-DNA data to infer genetic relationships among the Uros and their neighboring populations. The project leaders compared the Uros’ haplotype (genetic lineages) profiles with those of eight Aymara-, nine Quechua- and two Arawak-speaking populations from the western region of South America.
To learn more about the Uros people and their genetic ancestry, check out The Genetic History of Indigenous Populations of the Peruvian and Bolivian Altiplano: The Legacy of the Uros