An article published in Science Advances on Wednesday, July 15, explores human fecal biomarkers in coprolites in the Paisley Caves and found that they were occupied by Pre-Clovis people.
For many decades many archeologists believed that the earliest people to arrive in North America were the Clovis culture, named after their designs of arrowheads and other tools, which was around 13,000 years ago. Over the past several years more evidence has begun to challenge the idea that the Clovis culture was the first people in North America. New evidence from the Paisley Caves now shows that people were living in the Paisley and Summer Lake area long before the Clovis culture began.
In a new study of droppings at the Paisley Caves by Professor Lisa-Marie Shillito, an archeologist at the University of Newcastle in England, looked for radiocarbon evidence of the earliest droppings in the caves along with her team.
In a statement Shillito said that evidence has become accepted that there were pre-Clovis populations in America and that Paisley Caves are one of the key case studies for these populations as it is one of only a few places that have archeological material that can be dated.
Some of that material is preserved dung called coprolites. Co-author Dennis Jenkins, research associate at the University of Oregon, started excavating the Paisley Caves in 2007. He recently found a new set of coprolites at the lowest levels of the dig and was able to date them to 14,000 years old.
Worried about contamination from other humans, and to make sure they were not left by animals, Shillito’s team analyzed droppings in 2017 using a technique that looks for organic compounds called lipids. Unlike looking at DNA in the preserved dung, it is difficult to accidentally contaminate dung using the method to look for lipids. Using information from the lipid study and DNA, it is all but certain that the dung belonged to people who visited the Paisley Caves 14,000 years ago.
Not only does the study show that people lived and stayed at the Caves, coprolites also show how people lived back then including diet and health.
The preserved dung, helped by the dry southeastern Oregon heat, shows that the people that called the caves home had a varied diet and did not just rely on hunting big game such as mammoths.
Included in the information was digested seed coatings, rodent bones and the outer castings of insects along with organic compounds from plants.
“What you largely find is that maybe they were hunting large animals sometimes, but on a day-to-day basis their diets were a lot more varied and diverse,” said Shillito.
Unlike other archeological sites the coprolites are not concentrated in latrines or other central rubbish pits that came when permanent settlements became more common. Instead the droppings have been left where they lay, something that Shillito says makes sense for a nomadic people who would have used the cave sporadically.
The team is working on studying the entire assemblage of coprolites laid down in the Paisley Caves, to see how diets changed as shifts happened in the climate and environment.
For the Science Advances article visit advances.sciencemag.org/content/6/29/eaba6404.