Microtomographic archive of fossil hominin specimens from Kromdraai B, South Africa.

The Ditsong National Museum of Natural History (DNMNH) and the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) established a collaboration in 2010 to scan fossil hominin specimens housed at DNMNH using microtomography (microCT). The goal of this collaboration is to facilitate research and create a 'virtual copy' of the fossils for the DNMNH records. Within the context of this ongoing collaboration, the focus of this contribution is the fossil hominin material from the site of Kromdraai B, South Africa. The goals are to 1) formally publish the microCT scans of the Kromdraai material and facilitate their availability to the scientific research community, 2) address uncertainties regarding specimen accession numbers, 3) highlight internal aspects of anatomy revealed through the microCT scans, and 4) clarify the hominin status of a number of postcranial specimens. Finally, 2D images of surface models, a 3D PDF surface model, a movie of each microCT volume, and the original microCT volume of each specimen are made available via an open access online archive (http://paleo.eva.mpg.de).

The first hominin from the early Pleistocene paleocave of Haasgat, South Africa.

Haasgat is a primate-rich fossil locality in the northeastern part of the Fossil Hominid Sites of South Africa UNESCO World Heritage Site. Here we report the first hominin identified from Haasgat, a partial maxillary molar (HGT 500), that was recovered from an ex situ calcified sediment block sampled from the locality. The in situ fossil bearing deposits of the Haasgat paleokarstic deposits are estimated to date to slightly older than 1.95 Ma based on magnetobiostratigraphy. This places the hominin specimen at a critical time period in South Africa that marks the last occurrence of Australopithecus around 1.98 Ma and the first evidence of Paranthropus and Homo in the region between ∼2.0 and 1.8 Ma. A comprehensive morphological evaluation of the Haasgat hominin molar was conducted against the current South African catalogue of hominin dental remains and imaging analyses using micro-CT, electron and confocal microscopy. The preserved occlusal morphology is most similar to Australopithecus africanus or early Homo specimens but different from Paranthropus. Occlusal linear enamel thickness measured from micro-CT scans provides an average of ∼2.0 mm consistent with Australopithecus and early Homo. Analysis of the enamel microstructure suggests an estimated periodicity of 7-9 days. Hunter-Schreger bands appear long and straight as in some Paranthropus, but contrast with this genus in the short shape of the striae of Retzius. Taken together, these data suggests that the maxillary fragment recovered from Haasgat best fits within the Australopithecus-early Homo hypodigms to the exclusion of the genus Paranthropus. At ∼1.95 Ma this specimen would either represent another example of late occurring Australopithecus or one of the earliest examples of Homo in the region. While the identification of this first hominin specimen from Haasgat is not unexpected given the composition of other South African penecontemporaneous site deposits, it represents one of the few hominin localities in the topographically-distinct northern World Heritage Site. When coupled with the substantial differences in the mammalian faunal communities between the northern localities (e.g., Haasgat, Gondolin) and well-sampled Bloubank Valley sites (e.g., Sterkfontein, Swartkrans, Kromdraai), the recovery of the HGT 500 specimen highlights the potential for further research at the Haasgat locality for understanding the distribution and interactions of hominin populations across the landscape, ecosystems and fossil mammalian communities of early Pleistocene South Africa. Such contextual data from sites like Haasgat is critical for understanding the transition in hominin representation at ∼2 Ma sites in the region from Australopithecus to Paranthropus and early Homo.

Surface Model and Tomographic Archive of Fossil Primate and Other Mammal Holotype and Paratype Specimens of the Ditsong National Museum of Natural History, Pretoria, South Africa.

Nearly a century of paleontological excavation and analysis from the cave deposits of the Cradle of Humankind UNESCO World Heritage Site in northeastern South Africa underlies much of our understanding of the evolutionary history of hominins, other primates and other mammal lineages in the late Pliocene and early Pleistocene of Africa. As one of few designated fossil repositories, the Plio-Pleistocene Palaeontology Section of the Ditsong National Museum of Natural History (DNMNH; the former Transvaal Museum) curates much of the mammalian faunas recovered from the fossil-rich deposits of major South African hominin-bearing localities, including the holotype and paratype specimens of many primate, carnivore, and other mammal species (Orders Primates, Carnivora, Artiodactyla, Eulipotyphla, Hyracoidea, Lagomorpha, Perissodactyla, and Proboscidea). Here we describe an open-access digital archive of high-resolution, full-color three-dimensional (3D) surface meshes of all 89 non-hominin holotype, paratype and significant mammalian specimens curated in the Plio-Pleistocene Section vault. Surface meshes were generated using a commercial surface scanner (Artec Spider, Artec Group, Luxembourg), are provided in formats that can be opened in both open-source and commercial software, and can be readily downloaded either via an online data repository (MorphoSource) or via direct request from the DNMNH. In addition to providing surface meshes for each specimen, we also provide tomographic data (both computerized tomography [CT] and microfocus [microCT]) for a subset of these fossil specimens. This archive of the DNMNH Plio-Pleistocene collections represents the first research-quality 3D datasets of African mammal fossils to be made openly available. This simultaneously provides the paleontological community with essential baseline information (e.g., updated listing and 3D record of specimens in their current state of preservation) and serves as a single resource of high-resolution digital data that improves collections accessibility, reduces unnecessary duplication of efforts by researchers, and encourages ongoing imaging-based paleobiological research across a range of South African non-hominin fossil faunas. Because the types, paratypes, and key specimens include globally-distributed mammal taxa, this digital archive not only provides 3D morphological data on taxa fundamental to Neogene and Quaternary South African palaeontology, but also lineages critical to research on African, other Old World, and New World paleocommunities. With such a broader impact of the DNMNH 3D data, we hope that establishing open access to this digital archive will encourage other researchers and institutions to provide similar resources that increase accessibility to paleontological collections and support advanced paleobiological analyses.