Cornelia-Uitzoek, South Africa

Cornelia-Uitzoek (27.160° S, 28.878° E) is an Early Pleistocene fossil locality with Acheulean and Middle Stone Age (MSA) artifacts in the Schoonspruit Valley, a tributary of the Vaal River, in the northeastern Free State Province of South Africa (Fig. 1). It consists of fluvial gravel and clay beds that fill a channel cut into Permian Ecca Group mudstones (Karoo Supergroup). The fossil locality on the farm of Uitzoek was discovered by local schoolchildren and first investigated in the 1930s by Dr. E.C.N. van Hoepen, director of the National Museum in Bloemfontein. The fossil assemblage from Uitzoek is the type fossil (fossile directeur) of the Cornelian Land Mammal Age (LMA) of southern Africa (Hendey, 1974) and records a transitional stage in faunal evolution between the Makapanian LMA (c. 3.0 Ma–1.0 Ma) and the Florisian LMA (c. 0.773 Ma–0.011 Ma). The Cornelian LMA represents the initial phase in the evolution of unique open and wetland ecosystem habitats that resulted in the radiation and expansion of herbivore populations in the semi-arid interior during the Early and Middle Pleistocene. These species continued to evolve and proliferate during the Florisian LMA (Brink, 2005, 2016; Brink et al., 2012, 2022; Cooke, 1974; Klein, 1984). The main fossil-bearing bone bed and Acheulean artifacts at Cornelia-Uitzoek are contained within normal polarity basal clays assigned to the Jaramillo subchron between c. 1.07 and c. 1.00 Ma (Brink et al., 2012).