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Authors requiring further information regarding Elsevier’s archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright Author's personal copy Journal of Human Evolution 59 (2010) 685e691 Contents lists available at ScienceDirect Journal of Human Evolution journal homepage: www.elsevier.com/locate/jhevol News and Views Initial fossil discoveries from Hoogland, a new Pliocene primate-bearing karstic system in Gauteng Province, South Africa J.W. Adams a,b,*, A.I.R. Herries c, J. Hemingway b, A.D.T. Kegley a,b, L. Kgasi d, P. Hopley e, H. Reade f, S. Potze d, J.F. Thackeray g a Biomedical Sciences Department, Grand Valley State University, 312 Padnos Hall, Allendale, MI 49401, USA b School of Anatomical Sciences, University of the Witwatersrand Medical School, 7 York Road, Parktown, Johannesburg 2193, Republic of South Africa c UNSW Archaeomagnetism Laboratory, Integrative Palaeoecological and Anthropological Studies, School of Medical Sciences, University of New South Wales, Kensington NSW 2052, Sydney, Australia d Department of Palaeontology and H.O.P.E., Ditsong National Museum of Natural History, Kruger Street, Pretoria 0001, Republic of South Africa e Department of Earth and Planetary Sciences, Birkbeck College, University of London, Malet Street, London WC1E 7HX, UK f Department of Archaeology, University of Cambridge, Cambridge CB2 3DZ, UK g Institute for Human Evolution, University of the Witwatersrand, Private Bag 3, Johannesburg 2050, Republic of South Africa article info palaeocave, located in the Schurveberg (Farm Vlakplaats 354 JR; Gauteng Province; 2548048.3000S, 280020.4000E). Given that Article history: Hoogland lies on the former Hausleitner property and Broom’s Received 11 March 2010 descriptions of the locality, Hoogland likely represents a source for Accepted 1 July 2010 at least some of the ‘Schurveberg collection’ fossils. Keywords: This announcement provides a primary description of the Pliocene geology and stratigraphy of the Hoogland cave system and prelim- Theropithecus inary data from paleomagnetic, isotopic and macromammalian Cave geology faunal analysis from ex situ sediments. The results of these analyses Paleomagnetism are then used to provide a provisional date for the deposits. Site geology and paleomagnetism Introduction The Hoogland site includes an active cave system and a series of In 1936, Robert Broom explored fossil-bearing breccias from paleokarstic fossil-bearing deposits exposed during opencast spe- a previously mined cave system on the Hausleitner property near leothem mining. Until recently, the only entrances into the active the Hennops River, 22.5 km west of Pretoria in the Schurveberg system would have been a series of deep circular shafts running mountain region (Broom, 1936; Fig. 1). Broom collected a series of across the hillside above the fossil site. However, opencast lime fossil specimens from this site and other paleocaves in the region, mining of the paleokarstic deposit in the early 20th century broke including the type specimen of Papio (Dinopithecus) ingens (SB 7), through into a large chamber at the far reaches of this modern and a ‘Felis whitei’ mandible (TM 856; now attributed to Mega- system. The lime miners then followed the open cavities removing ntereon cultridens; Turner, 1987), that comprise the ‘Schurveberg any large quantities of speleothem. collection’ at the Ditsong (formerly Transvaal) Museum, Pretoria. A remnant of a similar circular shaft can be seen against the However, discoveries at Sterkfontein and later involvement at the northern wall of the mined cavity and indicates the deep vertical other Blaauwbank River Valley sites (e.g., Swartkrans and Krom- morphology of the entrance to the paleocave. The formation of draai) appears to have permanently forestalled Broom’s return to speleothems at the base of the ancient shaft suggests it was deep, or the Schurveberg region. In 2008, our team began the first in situ that an upper cave existed and was not subject to exterior conditions excavation and processing of ex situ deposits from the Hoogland that form more tufa-like deposits (see Herries et al., 2006b). Exog- enous material that fell down this shaft accumulated as a large talus slope at its base. This material was then periodically winnowed into * Corresponding author. a lateral cavern, depositing a series of interstratified siltstones, E-mail addresses: [email protected] (J.W. Adams), [email protected] gravels and flowstones. As a result, and in contrast with many South (A.I.R. Herries), [email protected] (J. Hemingway), kegleya@gvsu. African Plio-Pleistocene cave systems (e.g. Sterkfontein), the Hoog- edu (A.D.T. Kegley), lkgasi@nfi.museum (L. Kgasi), [email protected] (P. Hopley), [email protected] (H. Reade), potze@nfi.museum (J.F. Potze), francis.thackeray@ land deposits formed with an inclined ‘layer cake-like’ stratigraphy. wits.ac.za (J.F. Thackeray). Bone-rich clastic deposits are interstratified with flowstone lenses 0047-2484/$ e see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.jhevol.2010.07.021 Author's personal copy 686 J.W. Adams et al. / Journal of Human Evolution 59 (2010) 685e691 Figure 1. Topographic map of the Hoogland locality in reference to nearby Plio-Pleistocene fossil sites. Contour lines equal 20 m. radiating from a series of superimposed, large stalagmite bosses formed at various periods on top of the talus cone. While some portions of the sequence have been partially obscured by mining rubble, there is continuity in exposed deposits between the upper layers at the base of the entrance shaft and the lower layers in the lateral chamber. The overall effect of this depositional history was to produce ‘flowstone bounded units’ (FBUs) as seen at Gladysvale (Pickering et al., 2007) and Buffalo Cave (Herries et al., 2006b). The stratigraphy is therefore described in terms of FBUs and sedimentologically distinct zones (siltstone, gravel, breccia, speleothem, etc.; Fig. 2). The deposits in the lower part of the sequence are horizontally bedded on the flat floor of what was a small chamber, and were deposited under alternating subaerial and subaqueous environments. The deposits of the upper part of the sequence are partly inclined to the south due to their deposition on the edge of the original talus cone running from the base of the entrance shaft in a subaerial environment. The base of the Hoogland paleocave sequence consists of 50 cm of exposed vuggy (inclusion-filled) speleothem, overlain by 60 cm of clean banded flowstone with interstratified layers rich in organic inclusions. This is termed the ‘southern basal speleothem’ (SBS). The top 25 cm of the SBS has occasional isolated clastic layers due to the formation and infill of small gour pools (pools of water surrounded by a rimstone dam) within the flowstone. Above the SBS is 30 cm of siltstone deposits with thin layers of subaqueous mammillary spe- leothem, suggesting formation in deeper pools. The lower half of this layer appears to represent a break in clastic deposition into the pools, Figure 2. Stratigraphy and magnetic polarity (Ogg and Smith, 2004) for the various ‘ ’ while the upper 15 cm represents dirty mammillary speleothem flowstone bounded units (FBUs) and sedimentological phases of deposition at the where clastic deposition had recommenced. This unit is termed the Hoogland fossil site. Author's personal copy J.W. Adams et al. / Journal of Human Evolution 59 (2010) 685e691 687 Table 1 Table 1 (continued) Hoogland faunal assemblage Taxon NISP MNI Taxon NISP MNI Class Reptilia Class Mammalia Family Boidae Order Primates Subfamily Pythoninae Family Cercopithecidae Indet. 2 1 Subtribe Papioninae Theropithecus oswaldi oswaldi 11Total 1005 76 Indeterminate 1 1 Order Artiodactyla Family Bovidae ‘siltstone and subaqueous speleothem’ (STSAS). The lateral extent of Tribe Antilopini these deposits is unknown due to the infill of rubble to the north of Antidorcas bondi 21the site, but it appears that this layer formed synchronously as Antidorcas recki 10 4 fl Antidorcas sp. 6 2 subaerial owstone was forming towards the top of the talus slope. Antilopini indet. 3 1 This is the end of the basal zone of stratigraphy that is dominated by subaerial and subaqueous speleothem deposition, which is collec- Tribe Alcelaphini ‘ ’ Indeterminate (Class II) 17 6 tively termed the Basal Speleothem (BSP; Fig. 2). Indeterminate (Class III) 15 6 The BSP deposits are overlain by over 5 m of banded siltstone, conglomerate and breccia deposits that represent alternating Tribe Cephalophini cf. Sylvicapra sp. 1 1 periods of erosion, collapse, and periodic flooding events where Cephalophini indet. 2 1 clastic material that had entered the system through the vertical Tribe Neotragini shaft were washed from the top of the talus cone towards the back Oreotragus oreotragus 63wall of the cave. This sequence can be subdivided into three major cf. Raphicerus sp. 2 2 depositional zones based on sedimentological characteristics of the Neotragini indet. 7 4 deposits, or five flowstone bounded units (FBUs) that represent Tribe Reduncini discrete periods of clastic deposition covered by capping flow- Kobus sp. 1 1 stones. The lowest zone, ‘Basal Siltstone’ (BST) consists of alter- Redunca sp. 33 11 nating sequences of fine-grained conglomerate overlain by Reduncini indet. 5 2 siltstone deposits that represent alternating flooding events. These Tribe Tragelaphini deposits are seemingly entirely sterile of fossils. BST consists of Tragelaphus strepsiceros 21FBU1 and the lower part of FBU2.