Cranial morphology of early Americans from Lagoa Santa, Brazil: Implications for the settlement of the New World

Cranial morphology of early Americans from Lagoa Santa, Brazil: Implications for the settlement of the New World

Abstract
Comparative morphological studies of the earliest human skeletons of the New World have shown that, whereas late prehistoric, recent, and present Native Americans tend to exhibit a cranial morphology similar to late and modern Northern Asians (short and wide neurocrania; high, orthognatic and broad faces; and relatively high and narrow orbits and noses), the earliest South Americans tend to be more similar to present Australians, Melanesians, and Sub-Saharan Africans (narrow and long neurocrania; prognatic, low faces; and relatively low and broad orbits and noses). However, most of the previous studies of early American human remains were based on small cranial samples. Herein we compare the largest sample of early American skulls ever studied (81 skulls of the Lagoa Santa region) with worldwide data sets representing global morphological variation in humans, through three different multivariate analyses. The results obtained from all multivariate analyses confirm a close morphological affinity between South American Paleoindians and extant Australo-Melanesians groups, supporting the hypothesis that two distinct biological populations could have colonized the New World in the Pleistocene/Holocene transition.

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Discussion and Conclusions
The three different quantitative analyses undertaken in this study demonstrate that the first South Americans exhibit a cranial morphology that is very different from late and modern Northeastern Asians and Amerindians (short and wide neurocrania; high, orthognatic faces; and relatively high and narrow orbits and noses) but very similar to present Australians/Melanesians and Africans, especially with the former (narrow and long neurocrania; prognatic, low faces; and relatively low and broad orbits and noses). Taking into account the large number of early specimens used in this study, this trend is unlikely to be a result of sample bias. The phenomenon cannot, as well, be said to represent the result of microevolutionary processes restricted to Lagoa Santa because the same cranial pattern has already been described in places as distant and as ecologically different as Southern Chile [Magellan’s Strait (19)], Colombia [Sabana de Bogotá (20, 21)], Mexico [Mexico Basin (22) and Baja California (23)], United States [Florida (24)], and elsewhere in Brazil [Bahia (25) and São Paulo (26)] (Fig. 4)

This item seems to have been written before the mtDNA type M was found in an ancient West American site. And the complete obliteration of a pre-existing set of Y and Mt DNA now looks entirely possible, as this seems to have happened in North Africa during the Aterian. I’m for a multiple colonisation scenario involving Australoids, Jomon, Western Europe/North Africa and finally the Mongoloid Asians.

For anyone not familiar with very ancient American sites, some are now dating 40k to 5ok old in Brazil and South East America. The  Pedra Furada  site and the Topper site are the ones that spring to mind.

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