Anthropologists would prefer to use "Upper Paleolithic" for late ice-age cultures and "European Early Modern Humans" for the first Homo sapiens to arrive on the continent. If they had their druthers, they wouldn’t even refer to species, just to technologies and their relationship to the great glacial phases, or rather to their marine isotope stages.
Abri de Cro-Magnon was an archeological site in Aquitaine in southwestern France discovered in 1868 that contained remains of four skeletons that clearly weren’t Neanderthal. They probably were deliberately buried at the back of the cave. The bones were stained with red ochre and surrounded by perforated shell and animal tooth ornaments. Tools were made from flint and bone. Stone lined hearths and remains of reindeer and mammoths also were found in the limestone rock shelter.
The site, dated to between 30,000 and 32,000 years ago, was typical of those found later. It may be imprecise to make it an eponym for an era, but it’s much easier to remember than the alternatives.
Modern humans, Homo sapiens sapiens, emerged about 200,000 years ago as the Riss glacier was forming.
No species is static. Genetic mutations occur in every generation. In time, accumulations of significant changes are enough to form distinctive subgroups biologists call haplogroups.
DNA studies of the Y chromosome tell us Native Americans belong to the Q group and modern Europeans to the R. They also confirm the ancestor of both was L3, who evolved in Africa.
After L3 moved onto the Arabian peninsula, haplogroup N coalesced about 71,000 years ago. The expansion into Europe occurred about 50,000 years ago, or about 20,000 years before the Cro-Magnon burial.
The N population also diffused east. Haplogroup Q developed in northern Asia somewhere between 22,000 and 17,000 years ago, during the last glacial maximum of the Würm period from the M haplogroup via the intermediate P grouping. The M group is thought to have emerged 60,000 years ago, the P between 27,000-45,000 years ago.
Maulucioni’s reconstruction of the diffusion of Q shows most Native Americans, including local Tewa speakers are part of that stream. A team lead by Morten Rasmussen established the DNA of an infant buried in Montana around 10,000 years ago (8000 bc) was part of the dark purple on the map below.
Maulucioni also shows the areas where the Q marker on the Y chromosome has been diluted by other groups. The rosy purple corresponds roughly with the later influx of Athabascan and Algonquin speakers. Navajo and Apache are part of the first linguistic group, now called Na-Dené.
The medium purple represents the Inuit and Eskimoes.
More than 40,000 years may have passed between the time the first Homo sapiens moved into Europe and some migrated across the Bering Strait into North America. If it took women twenty years to reproduce, that was 2,000 generations of genetic change and cultural continuity.
Anthropologist working with Jean-Pierre Bocquet-Appel have tried to estimate the number of N-type individuals living in Europe using the known characteristics of food animals. They classified modern hunting groups by their prey and climate.
Next they used the modern groups’ demographic profiles as indicators of numbers of hungry beings each biome could support. That is, they recognized the diet of reindeer in Lappland today differs from that of reindeer in paleolithic Aquitaine.
From what was known about each site and the climate at the time, they then estimated populations for each. From there, they calculated the Cro-magnon total from number of sites.
They believed from the first entry of modern Homo sapiens to the last cold peak in the Würm glacial, the number averaged 4,400 to 5,900 inhabitants. Some 16,500 years ago, the climate began slowly warming and the population expanded to 28,800 inhabitants.
By way of comparison, San Juan pueblo counted 6,748 in the 2010 census. The combined total for our local zip codes that year was about 24,200 spread from Santa Clara to Valverde over 190 square miles.
Notes:
Advameg, Inc. Zip code data on City-Data website, run by Lech Mazur. The local zip codes are: Española and Santa Clara (87532), Santa Cruz (87533), Alcalde to Leyden (87511), and Chamita, San Juan and Velarde (87566).
Bocquet-Appel, Jean-Pierre, Pierre-Yves Demars, Lorette Noiret, and Dmitry Dobrowsky. "Estimates of Upper Palaeolithic Meta-Population Size in Europe from Archaeological Data," Journal of Archaeological Science 32:1656-1668:2005.
Rasmussen, M., et alia. "The Genome of a Late Pleistocene Human from a Clovis Burial Site in Western Montana," Nature 506:225-229:2014.
Stringer, Christopher B. and Alison S. Brooks. "Cro-Magnon," in Eric Delson, Ian Tattersall, John Van Couvering, and Alison S. Brooks, Encyclopedia of Human Evolution and Prehistory, 2004 edition.
Wikipedia entries on various haplogroups.
Maps:
1. Metspalu, M., et alia. "Suggested Migratory Route of the ‘Out of Africa’ Migration According to Mitochondrial DNA," BioMed Central Genetics 5:26:2004.
2. Maulucioni. "Haplogroup Q (Y-DNA) Distribution," Wikimedia Commons, 16 July 2010.
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