Lithic networks reveal early regionalization in late Pleistocene North America

• Our study uses data from 84 Clovis lithic assemblages from across North America.
• Raw materials co-occurring in assemblages are used to construct lithic networks.
• Analyses reveal three large isolated, mostly spatially discrete, lithic networks.
• The lithic networks correspond with regional differences in Clovis point form.
• We suggest that the pattern of Holocene cultural regionalization begins with Clovis.

North America was colonized by hunter–gatherer populations during the late Pleistocene, and the Clovis culture is the earliest well-documented evidence of this event. Long-standing questions about the colonization process persist, including the extent to which low-density populations maintained contact across the continent and if foraging territories overlapped or were spatially-discrete. Here, we use a network approach to examine the spatial structure of land use associated with the earliest hunter–gatherer populations in North America. In particular, we examine the co-occurrence of raw materials used for stone tool manufacture at archaeological sites across the continent. Using a database of 84 Clovis assemblages we show that there are three large isolated, mostly spatially-discrete, lithic exploitation networks across the continent. These regions closely correspond to previously identified differences in Clovis point form, suggesting that Clovis populations were becoming regionally distinct. This process of cultural diversification that begins in the late Pleistocene, continues to develop into the Holocene.