Pinnacle Point Cave 13B (Western Cape Province, South Africa) in context: The Cape Floral kingdom, shellfish, and modern human origins.

Genetic and anatomical evidence suggests that Homo sapiens arose in Africa between 200 and 100ka, and recent evidence suggests that complex cognition may have appeared between ~164 and 75ka. This evidence directs our focus to Marine Isotope Stage (MIS) 6, when from 195-123ka the world was in a fluctuating but predominantly glacial stage, when much of Africa was cooler and drier, and when dated archaeological sites are rare. Previously we have shown that humans had expanded their diet to include marine resources by ~164ka (±12ka) at Pinnacle Point Cave 13B (PP13B) on the south coast of South Africa, perhaps as a response to these harsh environmental conditions. The associated material culture documents an early use and modification of pigment, likely for symbolic behavior, as well as the production of bladelet stone tool technology, and there is now intriguing evidence for heat treatment of lithics. PP13B also includes a later sequence of MIS 5 occupations that document an adaptation that increasingly focuses on coastal resources. A model is developed that suggests that the combined richness of the Cape Floral Region on the south coast of Africa, with its high diversity and density of geophyte plants and the rich coastal ecosystems of the associated Agulhas Current, combined to provide a stable set of carbohydrate and protein resources for early modern humans along the southern coast of South Africa during this crucial but environmentally harsh phase in the evolution of modern humans. Humans structured their mobility around the use of coastal resources and geophyte abundance and focused their occupation at the intersection of the geophyte rich Cape flora and coastline. The evidence for human occupation relative to the distance to the coastline over time at PP13B is consistent with this model.