Late Pleistocene paleoenvironments and social dynamics in the southern Lower Mississippi River Valley

Archaeologists studying the Late Pleistocene and Early Holocene records in the Southeast have made significant methodological and theoretical contributions to our understanding of the earliest Native American record. In this paper, we briefly review these contributions. We then present a geographic case study of the southern Lower Mississippi River Valley. Relying on border, behavioral ecological, and cultural transmission theories, we show that due to terminal Pleistocene environmental conditions, this region was only sparsely inhabited until the post-Clovis unfluted period (∼12,100 years ago) and not fully settled until San Patrice populations established the region as their homeland at the end of the Younger Dryas. During this settlement and emplacement process, the Mississippi River became a permeable but clear social boundary marker.