Role of Coastlines in Behavioral Development

With National Science Foundation support, a research team conducts archaeological and paleoenvironmental research to study the role of coastal habitats in the survival of early humans. Much understanding of human evolution and the environments that mediated it derive from a limited geographical range of fossil and archaeological sites. However, our lineage (Homo sapiens) is believed to have evolved from diverse regional metapopulations. Testing this idea remains hindered by a lack of research in a range of critical ecosystems that may hold vital fossil and behavioral records. This project generates new empirical data in the form of stone artifacts, and paleoenvironmental and geochronological (age) records. The study contributes to understanding of the range of habitats early humans exploited and the behavioral innovations they developed to survive in coastal ecosystems. The resulting datasets are useful for testing the role of coastal ecozones as refugia during extreme climate conditions. Given the growing threat of climate change, paleoenvironmental datasets can be utilized by scientists for modeling future extreme events and ensuing ecosystemic responses in coastal environments, which are vital habitats for human survival today and in the future. The scientific questions addressed by the project are- when and how frequently were coastal zones occupied? What kinds of climatic/environmental conditions made the coastal region appealing for human habitation, and do such settlements represent human responses to extreme climatic events? What adaptive behaviors sustained human survival in such a region? The research team utilizes cutting edge data recovery and analytic methods to answer these questions, namely, i) fieldwork- which involves survey and excavation to collect cultural remains (stone artifacts), geomorphic investigation to establish the sedimentary history of the artifact-bearing deposits and identify signatures of past climate change, and collection of sediments subject to radiometric dating and paleoenvironmental proxy data recovery (such as pollen, phytolith, and carbon and nitrogen isotopes records), and ii) laboratory analyses of the recovered artifacts and sediments. To establish the ages of the sites, the team uses optically stimulated luminescence (OSL) dating technique. Pollen, phytolith, and carbon and nitrogen isotopes datasets derived from the sampled sediments allow reconstruction of the vegetation history of the region, which are key to inferring the types of resources available. The stone artifacts enable characterizing human technological and land-use behaviors. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.