AncientDNA and the Americas: current projects and challenges in anthropologicalresearch

Archaeologicaland genetic research about the timing and process of the colonization of theAmericas has revealed an early colonization 15,000-20,000 years ago followed bya “Beringian standstill”, and subsequent expansion from the North as well as alater expansion of Inuit-Aleut peoples. Ancient DNA analyses have contributed toour understanding of this process using first mitochondrial DNA and more recentlynuclear DNA data. While this larger picture is fairly well-resolved, researchabout the population history within different regions of the Americas bothpre-contact and during the contact period as well as at very local scales isstill uncommon. In this talk, I will discuss three projects in my laboratorythat focus on the regional and local scales. First, we are examining thepopulation history of the Caribbean using ancient DNA obtained from humanskeletal remains (dated 590 - 1280 cal AD) from three pre-contact Puerto Ricansites: Paso del Indio, Punta Candelero and Tibes. At the regional scale, recentarchaeological research suggests that indigenous groups in Puerto Rico stemmedfrom multiple and continuous migrations of continental indigenous populations,and we are testing hypotheses about these migrations. At the local level, weare investigating tomb and cemetery organization at two sites: the Maya Yaxunásite in the Yucatán peninsula (250-550 CE) and the MisiónSalesiana (AD 1893-1920) inTierra del Fuego. These different investigations also illuminate differences inpreservation as well as ethical concerns of descendant communities.