An archaeological team has found evidence of the highest altitude human occupied land in the southern Peruvian Andes dated 900 years earlier than previously documented.
Researchers at the University of Maine have documented the evidence nearly 4,500 meters above sea level (masl).
Despite cold temperatures, high solar radiation and low oxygen conditions at that altitude, hunter-gatherers colonized the remote, treeless landscapes about 12,000 years ago during the terminal Pleistocene - within 2,000 years after humans arrived in South America.
But the evidence implicated that there may have been more moderate late-glacial Andean environments and greater physiological capabilities for Pleistocene humans.
Kurt Rademaker, a University of Maine visiting assistant professor in anthropology has said that study of human adaptation to extreme environments was important in understanding our cultural and genetic capacity for survival.
The Pucuncho Basin sites has suggested that Pleistocene humans lived successfully at extreme high altitude, initiating organism selection, developmental functional adaptations and lasting biogeography expansion in the Andes.
The Pucuncho archaeological site, 4,355 masl, had included 260 formal tools, such as projectile points, nondiagnostic bifaces and unifacial scrapers up to 12,800 years old. Cuncaicha rock shelter, featured two alcoves at 4,480 masl, contained a "robust, well-preserved and well-dated occupation sequence" up to 12,400 years old. The rock shelter, with views of wetland and grassland habitats, featured sooted ceilings and rock art, and was likely a base camp.