Integrating Different Biological Evidence Around Some Microevolutionary Processes: Bottlenecks and Asian-American Arctic Gene Flow in the New World Settlement

Abstract

Excepting some specific efforts, most of the mainstream debate around the Americas' settlement has been directed by specialists dealing with partial evidence. Thus, discussions have been confined to particular academic and scientific environments with limited interchange among archeologists, physical anthropologists, linguists, geneticists, geologists, paleontologists, and so on. As a consequence, integrative views about a process that is complex by definition have been scarce and driven by confrontation rather than by a search for common results. Still, an increasing number of specialists are attempting to integrate different types of data. In our view, a proper way to do this is to focus the discussion around evolutionary or cultural processes and the putative patterns that such processes could have generated in the different types of data, which in turn, depend on the nature of the data. In this way, the analyses and conclusions can be interpreted as "model-bound" rather than purely inferential. In this paper, we first provide a brief summary of main differences among the two main sources of biological information - genetics and craniofacial size and shape - along with the main conclusions that the patterns of genetic and craniofacial variation provide. Furthermore, we exemplify the above-mentioned notion by discussing two particular processes and their hypothetical impact on genetic and craniofacial data: the influence of bottlenecks during the early dispersal and a putative zone of gene flow among Asian and American Circum-Arctic populations.