The broader geological setting of the cave is discussed in Dirks et al. (a) Simplified geological map showing the position of the Rising Star Cave (in grey); (b) close-up map of the Dinaledi Chamber showing the distribution of the dating samples, including: U-Th flowstone samples (yellow dots, black text); ESR samples (purple dots, orange text); and OSL samples (red dots, blue text).
Age estimates for the different samples are shown, with cross reference to Tables 1, 7 and 8.
naledi fossils are the largest collection of a single species of an ancient human-relative discovered in Africa.
After the discovery was reported, a number of questions still remained.
The fossils occur as a dense bone accumulation in mostly unconsolidated muddy sediment that largely originated from within the cave through weathering of the dolomite host rock (Dirks et al., 2015). In this paper we present results of uranium-thorium (U-Th) disequilibrium, electron spin resonance (ESR), radiocarbon, and optically stimulated luminescence (OSL) dating in combination with palaeomagnetic analyses, to provide ages for the fossils and surrounding deposits in the Dinaledi Chamber, and build upon the geological context described in Dirks et al. Dates acquired via U-Th and ESR techniques were obtained using a double blind approach for each technique to ensure robust, reproducible results, with each laboratory using their own analytical and computational approach.Species of ancient humans and the extinct relatives of our ancestors are typically described from a limited number of fossils. More than 1500 fossils representing at least 15 individuals of this species were unearthed from the Rising Star cave system in South Africa between 20.Found deep underground in the Dinaledi Chamber, the H.Approaches taken by each laboratory that contributed to this paper are described in detail in the methodology section. naledi and early Homo) and associated mammals, reptiles, and birds (e.g., Vrba, 1975, 1995; Brain, 1993; Tobias, 2000; Berger et al., 2010, 2015).The age of the hominins in the Dinaledi Chamber has implications for our understanding of the mode and tempo of the morphological evolution of hominins (Hawks and Berger, 2016), raising questions about evolutionary stasis and the role of refugia. For the past 3 million years, hominin-bearing deposits in caves formed in broadly similar settings, involving debris cone accumulations near cave openings (Partridge, 1973; Wilkinson, 1985; Brain, 1993; Pickering et al., 2007; de Ruiter et al., 2009; Dirks and Berger, 2013; Herries and Adams, 2013; Dirks et al., 2010, 2016b; Bruxelles et al., 2014; Stratford et al., 2014), with deposits cemented by carbonate-rich waters dripping from cave ceilings (e.g., Wilkinson, 1985; Pickering et al., 2011b).