In a sky-high archaeological dig, based near the peaks of the Peruvian Andes mountains, an international team of researchers unearthed the oldest-known evidence of human settlement high above sea level. In fact, the rock shelters and tool fragments found, date back roughly 12,000 years and lie 14,700 feet above coastal sea level at the base of the mountain range.
The discovery, which was documented and published in this week's issue of the journal Science, revealed that ancient human ancestors who had only arrived in South America 2,000 years before, were already scaling the rocky mountains and finding a home high off the sandy beaches. And researchers believe that this ability was thanks to some great genetic diversity within the travelling population, that allowed the group to adapt relatively quickly to mountainous living and harsh winter weather.
"Either they genetically adapted really, really fast within 2,000 years to be able to settle this area, or genetic adaptation isn't necessary at all" lead author of the study, Kurt Rademaker from the University of Maine says. "Our results demonstrated that despite cold temperatures and low-oxygen conditions, hunter-gatherers colonized extreme high-altitude Andean environments in the Terminal Pleistocene [era]."
Beginning his work in Peru in the 1990's, Rademaker and his colleagues were originally tipped off at the possibility of high-altitude living when ironically enough, studying 13,000 year old Paleoindian fishing camps on the coast of Peru called Quebrada Jaguay. Finding remnants of obsidian tools, Rademaker deduced that the tools had to have been fashioned roughly 100 miles away in the volcanically active Andes Mountains at the time. The distinct obsidian marker indicated to Rademaker that they should look higher as Paleoindians must have gone at some point to the highlands.
After years of searching a nearby plateau, Rademaker and his researcher colleagues discovered a rock shelter they believed was a temporary "base camp" of sorts where herders sheltered from the rain and cold winds. Decorated in rock art and filled with ancient tools, the shelter appeared to be an open-air workshop of sorts, and Rademaker says that it likely was an important hub in the trade-networks that supplied the coast.
While more contemporary stories of explorers and settlers who encountered tragic deaths when encountering mountain ranges have prevailed, altering the public perception of the safety of mountains, researchers say that in the ancient culture the mountains symbolized possibility. Filled with a myriad of resources, and unlike the beach they once inhabited below, the hunter-gatherers likely explored the high-peaks in search of large herd mammals and resources to trade with the communities of the coast.
"Study of human adaptation to extreme environments is important for understanding our cultural and genetic capacity for survival" Rademaker says.
