Two new papers published in Nature, document the findings from the Chiquihuite Cave site in central Mexico. Artifacts from the site ere first discovered in 2010, but there were difficulties traveling to and from the site. For that reason, archaeologists lived for 80 days between ’16 and ’17. They excavated over 1,900 stone tools. The artifacts were dated using both radiocarbon dating and optical stimulated luminescence, which was the premise of the first study.
Both dating techniques yielded two settlement eras. 88% of the stone tools came from the younger strata that dated between 16,000 to 12,200 years ago. Curiously, however there was an older layer that dated to 16,600 to 33,000 years old. That contained 12% of the stone tools.
These artifacts are clearly human made. You can see in the photos above and below, these tools show evidence of sculpting and napping to make flakes. Signs of butchering, like sulfur potassium and zinc is also found. Furthermore, the second study compares these artifacts to artifacts from 42 other sites, this style is unlike others, such as the Clovis, Western Stemmed and Berinngian cultures.
These two papers are highly impactful pair of studies. The peopling of the Americas occurred before the last glacial maximum, a time period between 26,500 to 19,000 years ago. In fact, that pushes back the dates of human occupancy of North America to as early as 33,000 years ago. That is over 10,00 years earlier than what we knew!