The first human settlement of the New World: a closer look at craniofacial variation and evolution of early and late Holocene Native American groups

DE AZEVEDO, SOLEDAD; QUINTO-SÁNCHEZ MIRSHA; PASCHETTA, CAROLINA ANDREA; GONZÁLEZ-JOSÉ, ROLANDO

QUATERNARY INTERNATIONAL

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2017 vol. 531 p. 152 - 167

1040-6182

During its expansion across the globe, Homo sapienssuccessfully survived to major adaptive challenges as species, invitingscientific research to plunge into the particularities of continentalsettlement dynamics. A recurrent paleoanthropological concern is aboutthe understanding of the great deal of craniofacial diversity thatevolved into the Americas, which includes a vector of continuum variationbetween a generalized morphology observed among humans groups leading theOut-of-Africa dispersion, and a derived set of craniofacial traitsclassically labeled as "mongoloid" and that would have arise in Asiaduring the Holocene. Here we use geometric morphometric techniques andmultivariate statistics along with quantitative genetic approaches tolook more closely into the human craniofacial evolutionary history duringthe Late Pleistocene-Early Holocene from Asia and the New World. Wedetected significant signals of deviation of the neutral evolutionaryexpectations, suggesting an important action of non-stochastic evolution(e.g. natural selection, phenotypic plasticity) in the Americas. We alsofound further support to the Recurrent Gene Flow model that refers to anancestral, founder population experiencing a standstill in Beringia, andexhibiting high within-group craniofacial variation. This original,internally variable stock would have been the ancestral source ofvariation that fuelled the subsequent local micro evolution of otherderived phenotypic patterns, giving origin to the craniofacial diversityobserved among Holocene Native American samples.