At https://anthropology.net/2020/07/22/new-archaeological-evidence-of-the-f… … the evidence comes from a cave in Mexico. New archaeological evidence of the first Amricans dated to 33,000 years ago. Two major papers in Nature concern the excavation of 1900 stone tools from sediments in a cave. They were dated in two ways. Firstly by carbon dating (and Bayesian methodology) and by optical stimulated luminescence. Two separate strata were found. The younger was dated between 16,000 and 12,200 years ago (basically end of Ice Age until late in Younger Dryas episode) – but the older and disputed layer has been dated from 33,000to 16,000 years ago. Already, critics are on their keyboards or making comments to the media. It seems the peopling of the Americas may even have begun prior to the Late Glacial Maximum.
See also https://cosmosmagazine.com/history/archaeology/evidence-for-early-arriva… … where one of the archaeologists is quoted as saying, 'human made flaked stone artefacts are there by the thousands, embedded in layered sedimentary deposits …'. The new date puts Clovis First to bed. Surprisingly, a lot of archaeologists are loathe to move much further back, in spite of growing evidence from a number of sites. They want to stick to the period between the end of the Ice Age and the beginning of the Younger Dryas for the arrival of humans in the Americas. They are reluctant to concede to dates earlier than that. It is a strong rearguard action. The first strata would have suited them perfectly. Unfortunately, there was another strata below that.