Nicolas Ray

TL;DR: It is shown that the initial peopling followed a southward expansion facilitated by the coast, with sequential population splits and little gene flow after divergence, especially in South America.

TL;DR: Using microbial populations, Hallatschek and colleagues have provided the first experimental evidence of surfing during spatial expansions and suggest that a single range expansion can create very complex patterns at neutral loci, mimicking adaptive processes and resembling postglacial segregation of clades from distinct refuge areas.

TL;DR: A simulation study examining the effect of a recent spatial expansion on the pattern of molecular diversity within a deme finds that the shape of the gene genealogies and the overall pattern of diversity within demes depend not only on the age of the expansion but also on the level of gene flow between neighboring demes, as measured by the product Nm.

TL;DR: Using DNA data from 50 nuclear loci sequenced in African, Asian and Native American samples, it is shown that a simple African replacement model with exponential growth has a higher probability as compared with alternative multiregional evolution or assimilation scenarios.

TL;DR: Evidence is observed of a higher level of diversity and lower level of population structure in western South America compared to eastern South America, a relative lack of differentiation between Mesoamerican and Andean populations, and a partial agreement on a local scale between genetic similarity and the linguistic classification of populations.