Originally posted by Kandinsky
reply to post by JohnnyCanuck
Sounds interesting about Monte Verde. 40 000 is still pretty good from our perspective. I recently read Charlie Hatchett pointing out how Valsequillo, Hueytlico is still coming up 400 000! Unless something has changed, it still seems to hinge on Sam Vanlangringham's (is that the right name?) diatom analysis...controversial.
From above link.
The estimated ages (18–24 ky) of the four pan-American haplogroups A2, B2, C1, and D1 are quite similar with an average value of 20 ky. Thus, if A2, B2, C1, and D1 entered the Americas without variation in the coding region – in other words, each with only a single (successful) founder sequence (the root haplotype), their entry into the Americas would have occurred right after the peak of the Last Glacial Maximum (LGM, centered at ~21.0 kya and extending from 19.0 to at least 23.0 kya ), or slightly earlier, so that a coastal (Pacific) route would have been the only option during such glacial periods. On the other hand, it is quite plausible that some intra-haplogroup variation – hardly noticeable at the level of HVS-I motifs – already existed in Beringia and was carried directly further south into the American double-continent.
From above link.
These data indicate that the initial migration of ancestral Amerindian originated in south-central Siberia and entered the New World between 20,000–14,000 calendar years before present (cal yr BP). These early immigrants probably followed a coastal route into the New World, where they expanded into all continental regions. A second migration that may have come from the same Siberian region entered the Americas somewhat later, possibly using an interior route, and genetically contributed to indigenous populations from North and Central America. In addition, Beringian populations moved into northern North America after the last glacial maximum (LGM) and gave rise to Aleuts, Eskimos, and Na-Dené Indians.