A cave in a remote part of Mexico was visited by humans around 30,000 years ago - 15,000 years earlier than people were previously thought to have reached the Americas.
Painstaking excavations of Chiquihuite Cave, located in a mountainous area in northern Mexico controlled by drugs cartels, uncovered nearly 2000 stone tools from a small section of the high-altitude cave.
Archaeological analysis of the tools and DNA analysis of the sediment in the cave uncovered a new story of the colonisation of the Americas which now traces evidence of the first Americans back to 25,000-30,000 years ago.
The results, which have been published in Nature today (July 22 2020), challenge the commonly held theory that the Clovis people were the first human inhabitants of the Americas 15,000 years ago.
DNA scientist Professor Eske Willerslev, of St John's College, University of Cambridge, and director of The Lundbeck Foundation GeoGenetics Centre, University of Copenhagen, led the study with archaeologist Dr Ciprian Ardelean, of the University of Zacatecas in Mexico.
Professor Willerslev said: "For decades people have passionately debated when the first humans entered the Americas. Chiquihuite Cave will create a lot more debate as it is the first site that dates the arrival of people to the continent to around 30,000 years ago - 15,000 years earlier than previously thought. These early visitors didn't occupy the cave continuously, we think people spent part of the year there using it as a winter or summer shelter, or as a base to hunt during migration. This could be the Americas oldest ever hotel."
The 10-year long research project raises more questions about the early humans who lived in the Americas than it solves.