Radiometric dating paper
Modern humans probably did not expand out of Africa until 50,000 to 80,000 years ago, recent genetic studies have shown.If California’s first settlers weren’t modern, then they would have to have been Neanderthals or perhaps members of another extinct human lineage.“It poses all sorts of questions,” said Thomas A. ”Some experts were intrigued by the research, but many archaeologists strongly criticized it, saying the evidence didn’t come close to supporting such a profound conclusion.“I was astonished, not because it is so good but because it is so bad,” said Donald K.Pike, a geochronology expert at the University of Southampton who was not involved in the new study.If early humans really did smash those mastodon bones 130,000 years ago, scientists will have to rethink how humans came to the Americas.Other researchers agreed that the dating methods, at least, were sound.“These results look about as good as it can get,” said Alistair W.
But other kinds of humans might have made the journey to North America much earlier.
Genetic studies strongly support the idea that those people were the ancestors of living Native Americans, arriving in North America from Asia.
If humans actually were in North America over 100,000 years earlier, they may not be related to any living group of people.
For decades, archaeologists have searched North and South America for the oldest evidence of occupation.
Last year, Canadian researchers reported that bones of caribou and other mammals found in the Yukon with cut marks, which they argue were man-made, date back 24,000 years. Waters, an archaeologist at Texas A&M University, and his colleagues reported that a stone knife and mastodon bones with cut marks found in a Florida sinkhole are about 14,500 years old.
That test revealed, to their surprise, that the bones were 130,000 years old.