A landmark archaeological site in Chile that shaped scientific understanding of when humans first arrived in the Americas may be tens of thousands of years younger than once believed, according to a new study published in the journal Science.
For nearly half a century, Monte Verde in southern Chile stood as the cornerstone of pre-Clovis archaeology. Scientists dated the site to approximately 14,500 years ago, making it one of the oldest known records of human settlement in the Western Hemisphere.
A team led by Todd A. Surovell of the University of Wyoming has now produced the first independent examination of the site since original excavations began in the 1970s. Their conclusion sharply contradicts the established dating.
Monte Verde: The site that defined American prehistory
The research team collected and analyzed sediment samples from multiple locations along Chinchihuapi Creek, which runs beside the site. During that process, they identified a layer of volcanic ash buried beneath the Monte Verde archaeological material. That ash traced back to a volcanic eruption roughly 11,000 years ago.
Because the artifacts sit above that ash layer, they cannot predate it. Based on this, Surovell and his colleagues determined Monte Verde is no older than 8,200 years, placing it in the Middle Holocene period.
Claudio Latorre, a co-author based at the Pontifical Catholic University of Chile, said the team conducted a complete reinterpretation of the site’s geology and reached a very different conclusion from earlier researchers.
The team also argued that natural processes, particularly stream erosion that shifted and blended sediment layers over centuries, likely caused earlier researchers to mistakenly associate ancient materials with the wrong time period.
Buried ash layer points to a far younger site
The conclusions have drawn sharp criticism. Michael Waters of Texas A&M University, who played no role in either the original excavations or the new study, said the findings amount to an unproven hypothesis that the presented data simply does not support.
Tom Dillehay of Vanderbilt University, who directed the original Monte Verde excavations, was equally dismissive. He argued the study overlooks an extensive body of reliably dated cultural evidence, pointing to artifacts recovered directly from the site, including a sharpened mastodon tusk, a wooden spear, and a fire-charred digging tool.
Other outside researchers raised concerns that the new team examined the terrain surrounding Monte Verde rather than the site itself, where geological conditions differ considerably. They also questioned whether the volcanic ash deposit ever extended across the full landscape.
Rethinking when humans first arrived in the Americas
Surovell defended the approach, saying the team gathered samples from within the site and from points both upstream and downstream along the creek.
The implications stretch well beyond a single site. Monte Verde’s original dating helped overturn the long-held belief that the Clovis people, who lived roughly 13,000 years ago, were the first humans to reach the Americas.
Surovell said independent re-examination of other early archaeological sites will be critical going forward, and expressed confidence that science, given sufficient time, will reach accurate conclusions.
