Expanded Explorations of the Dinaledi Subsystem, Rising Star Cave System, South Africa

Abstract

The Dinaledi Chamber of the Rising Star cave system has yielded a large assemblage of fossil hominin material, attributed to Homo naledi. The unusual taphonomic and geological situation of the assemblage suggested that the remains may have been deliberately deposited in the chamber. However, the route and mechanism of deposition of the remains within the Dinaledi Chamber are still uncertain. During the 2017—2018 field seasons, we expanded explorations of the passages surrounding the Dinaledi Chamber. These explorations improved our understanding of the cave’s spatial complexity, necessitating a revision of the way the spaces are named and described. The work supported the hypothesis that there is no alternate entrance into the system other than the Chute. The work also identified new fossil deposits in several remote passages, three of which contain material attributable to H. naledi. Here, we clarify the definition of the Dinaledi Subsystem and provide terminology for new fossil localities found in this portion of the Rising Star cave system. These results emphasize the complex depositional environment of the Dinaledi Subsystem and raise new questions about the process and timing of the fossil accumulations.