EVIDENCE IN THE BONES: THE LATE PLEISTOCENE/EARLY HOLOCENE HUMAN FOSSIL RECORD FROM THE WESTERN USA AND MEXICO

The timing, route and origin of the first colonization of the Americas remains a most contentious topic in human evolution. So far, in North America most early sites date to the latest Pleistocene reflecting the expansion of the Clovis tradition at around 11,500 years BP. But the picture is complicated by the fact that the earliest accepted occupation date is in South America, in Monte Verde, Chile with dates around 12,500 years BP(dates are quoted uncalibrated).

A review will be presented of the Late Pleistocene/Early Holocene human fossil evidence in the Western USA and Mexico, where very few human remains have been directly radiocarbon dated.

Examples of dated Paleoindians in Western USA include: the Anzick cranial fragments, Montana 11,500 years BP; the Santa Rosa Island femora 10,960 years BP; Buhl Woman, Idaho, 10,700 years BP; Spirit Cave Man, Nevada 9,410 years BP; Wizards Beach Man, Nevada 9,515 years BP and the controversial Kennewick Man, Washington 8,410 years BP.

More recently some Paleoindian remains have been directly radiocarbon dated in Mexico including: Peñon Woman III 10,755 years BP, Tlapacoya Man 10,100 years BP, Texcal Cave Man 7,480 years BP and San Vicente Chicoloapan Man 4,410 years BP.

Information derived from craniometric studies from these early populations, including preliminary results from the Mexican specimens, indicates that Paleoindian remains:

* Are diverse morphologically and in general lack characteristic Amerindian traits, with long an narrow skulls (dolicocephalic) and relatively short, narrow faces. * Appear more similar to southern Asians, Australians and populations of the South Pacific Rim than they do to northern Asians.

The evidence indicates that Late Pleistocene Paleoindians were different to Late Holocene and Modern Amerindian populations with Mongoloid affinities.

The small sample of directly dated Paleoindians currently available in North America and Mexico seems to indicate great levels of diversity for these early populations, with the possibility of several points of origin. However, there are no humans directly dated in the Americas older than 11,500 years BP.

Preliminary data will be presented showing the stable isotope composition from the few dated Mexican Paleoamericans and some megafauna (mainly Columbian mammoths) which indicate that the humans were probably consuming grazing herbivores, such as the mammoths.