Researchers recently went up to the Peruvian Andes mountains to explore one of the highest-altitude sites from the Pleistocene era during the Ice Age.
The main site explored, called Cuncaicha, was about 14698.2 feet above sea level. The researchers also looked at a nearby site where the inhabitants made tools out of stone. These sites are extremely high up and hard to live on, with harshly cold weather, low oxygen levels and high levels of radiation from the sun.
However, both sites seem to have been occupied for a long range of time, about 12,000 to 11,000 years ago.
"We don't know if people were living there year round, but we strongly suspect they were not just going there to hunt for a few days, then leaving. There were possibly even families living at these sites, because we've found evidence of a whole range of activities," said Sonia Zarrillo, one of the co-authors of the paper. Zarrillo is an archaeologist at the University of Calgary.
The researchers found signs of human inhabitance evidenced by pieces of human skulls, animal remains and stone tools, which seem to have been used for hunting and for treating animal hides and making things like blankets out of them. The types of animal remains found, which included the whole animal, not just the carcass, indicated that these people lived here for extended periods of time. Zarrillo said that if people just came up here to hunt, they would likely have only left behind the carcass, carrying the meat back to where they lived.
This site is an anomaly because scientists believe that people cannot live at such high altitudes unless they have a genetic adaptation that allows them to overcome things like the low oxygen levels. People living in the Andes today have genetically adapted to the elevated height, with higher lung capacities and higher concentrations of hemoglobin in their blood. It is not yet known whether the people living here had that genetic adaptation, or whether they were simply able to live despite the harsh conditions.
"What we're demonstrating is that these people either already developed that adaptation, or, it was possible for them to live in these altitudes for extended periods of time regardless. Finding this out is one of the goals of our future research," Zarrillo said.
The research study was published on Oct. 24 in the journal Science.
