More on First Americans

At https://phys.org/news/2020-07-humans-americas-years-earlier-previously.html … humans in the Americas 15,000 years earlier than mainstream allowed. The findings are published in two Nature articles – see for example https://doi.org/10.1038/s41586-020-2491-6 … and here we have an interview, short, with Dr Becurra-Valdera of the University of New South Wales in Australia, and Tom Higham of Oxford University. The research papers included various others. The people that travelled to the Americas, we are told, must have used maritime technology because the northern parts of North America were impenetrable and glaciated, and impassable by a land route. Herein lies the problem in accepting the new dates. It is thought a land route was not possible until 14,000 years ago. It adds, the ice sheet in North America lasted until 13,000 years ago. Did it? The Late Glacial Maximum came to an end somewhat earlier (depending on how you date the Older Dryas event and the Oldest Dryas event) and there was at least 2000 years of warming prior to the Younger Dryas event. We have evidence the Late Glacial Maximum ice sheet was extensive in NE North America and in NW Eurasia. However, large parts of Siberia, and Alaska, were unglaciated. It is assumed they had a very cold climate but as the migrants into the Americas have a Siberian origin one would think the mainstream model may be wrong in detail. If people arrived in the Americas  and lived there at the height of the Late Glacial Maximum and then mainstream needs to think outside the box. Playing around with the extremities of a hypothesized frozen north is burying your head in the sand. A better idea might be to have a  relook at the ice margins. Has mainstream got it right. The problem is inherent with Ice Age theory as it is assumed the whole of the northern hemisphere was glaciated – and no doubt it was. At different times.