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Pickering TR, Cazenave M, Clarke RJ, Heile AJ, Caruana MV, Kuman K, Stratford D, Brain CK, Heaton JL. First articulating os coxae, femur, and tibia of a small adult Paranthropus robustus from Member 1 (Hanging Remnant) of the Swartkrans Formation, South Africa. J Hum Evol 2025; 201:103647. [PMID: 40043506 DOI: 10.1016/j.jhevol.2024.103647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 12/19/2024] [Accepted: 12/31/2024] [Indexed: 04/08/2025]
Abstract
Since paleontological work began there in 1948, Swartkrans (South Africa) has yielded hundreds of Early Pleistocene hominin fossils, currently attributed to (in ascending order of quantity) cf. Australopithecus africanus, Homo spp., and Paranthropus robustus. The bulk of that large sample comprises craniodental remains, with (mostly fragmentary) postcranial materials being much less abundant at the site. In that context, our announcement here of the first articulating partial os coxae, nearly complete femur, and complete tibia of a young adult hominin (SWT1/HR-2), excavated from the <2.3 to >1.7-million-year-old Hanging Remnant (Member 1) of the Swartkrans Formation, represents an important addition to the understanding of hominin postural and locomotor behavior in Early Pleistocene South Africa. We provide qualitative and quantitative descriptions and initial functional morphological interpretations of the fossils, based mostly on external bone morphology. Epiphyseal fusion data, element dimensions, the crural index, and live body stature and mass estimates that we provide all indicate that SWT1/HR-2 is one of the smallest known adult hominins in the fossil record. We discuss the paleobiological implications of these findings in relation to our taxonomic diagnosis of SWT1/HR-2 as representing P. robustus.
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Affiliation(s)
- Travis Rayne Pickering
- Department of Anthropology, University of Wisconsin-Madison, Madison, WI, 53706, USA; Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, WITS 2050, South Africa.
| | - Marine Cazenave
- Department of Human Origins, Max Planck Institute for Evolutionary Anthropology, Leipzig, 04103, Germany; Division of Anthropology, American Museum of Natural History, New York, 10024, USA; Department of Anatomy, Faculty of Health Sciences, University of Pretoria, 0084, Pretoria, South Africa
| | - R J Clarke
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, WITS 2050, South Africa
| | - A J Heile
- Department of Anthropology, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Matthew V Caruana
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, WITS 2050, South Africa; Palaeo-Research Institute, University of Johannesburg, Auckland Park, 2006, South Africa
| | - Kathleen Kuman
- School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, Johannesburg, WITS 2050, South Africa
| | - Dominic Stratford
- School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, Johannesburg, WITS 2050, South Africa; Department of Anthropology, Stony Brook University, Stony Brook, NY, 11794, USA
| | - C K Brain
- Department of Vertebrates, Ditsong National Museum of Natural History (Transvaal Museum), Pretoria, 0001, South Africa
| | - Jason L Heaton
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, WITS 2050, South Africa; Department of Biology, University of Alabama at Birmingham, Birmingham, AL, 35205, USA
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Malherbe M, Pickering R, Stynder D, Haeusler M. The large mammal fossil fauna of the Cradle of Humankind, South Africa: a review. PeerJ 2025; 13:e18946. [PMID: 40017660 PMCID: PMC11867040 DOI: 10.7717/peerj.18946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2024] [Accepted: 01/16/2025] [Indexed: 03/01/2025] Open
Abstract
South Africa's Cradle of Humankind UNESCO World Heritage Site has remained the single richest source of hominin fossils for over ninety years. While its hominin specimens have been the subject of extensive research, the same is not true for its abundant faunal assemblages, despite their value in Plio-Pleistocene palaeoenvironmental reconstructions. Moreover, precise ages and depositional histories have been historically difficult to assess, though advancements in both relative and absolute dating techniques are changing this. This review explores the history of non-hominin large mammal faunal reporting, palaeoenvironmental reconstructions based on these fauna, and dating histories (with a focus on biochronology) at the following eight fossil-bearing sites of the Cradle that have been radiometrically dated with uranium-lead: Bolt's Farm, Cooper's Cave, Drimolen, Haasgat, Hoogland, Malapa, Sterkfontein and Swartkrans. Continued efforts to provide more precise and direct ages for sites using a variety of methods indicate that the bulk of Cradle deposits date to between 3 and 1.4 Ma. We find that, across almost all eight sites, there is little discussion or debate surrounding faunal reports, with some sites described by a single publication. Many of the reports are decades old with little review or reanalysis in the years following, emphasising the need for reviews such as this one. Our analysis of the data indicates that faunal-based paleoenvironmental reconstructions across sites commonly show a trend of wooded landscapes giving way to grasslands. We find that these reconstructions are primarily based on faunal abundance data, despite the availability of many other informative analytical techniques. The findings of this review highlight a need for more extensive and robust faunal reporting, as this will aid in understanding the context of these Cradle sites.
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Affiliation(s)
- Megan Malherbe
- Institute of Evolutionary Medicine, University of Zürich, Zürich, Switzerland
- Human Evolution Research Institute, University of Cape Town, Cape Town, South Africa
| | - Robyn Pickering
- Human Evolution Research Institute, University of Cape Town, Cape Town, South Africa
- Department of Geological Sciences, University of Cape Town, Cape Town, South Africa
| | - Deano Stynder
- Department of Archaeology, University of Cape Town, Cape Town, South Africa
| | - Martin Haeusler
- Institute of Evolutionary Medicine, University of Zürich, Zürich, Switzerland
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Webb NM. The Functional and Allometric Implications of Hipbone Trabecular Microarchitecture in a Sample of Eutherian and Metatherian Mammals. Evol Biol 2021. [DOI: 10.1007/s11692-021-09543-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
AbstractThe pelvis plays an active role in weight bearing and countering the ground reaction forces incurred by the hindlimbs thus making it a critical component of the locomotor skeleton. Accordingly, this anatomical region is theoretically ideal for inferring locomotor behavior from both external skeletal morphology and trabecular microarchitecture, with the latter possibly offering nuanced insights into the mechanical loading environment given its increased plasticity and higher turnover rate. However, trabecular microarchitecture is also known to be influenced by a variety of factors including body size, sex, age, genetic regulation, diet and activity level, that collectively hinder the ability to generate consistent functional inferences. In this study, a comparative sample of mammals (42 species spanning four orders) of varying sizes, yet comparable locomotor repertoires, were evaluated to determine the effects of body size, phylogeny and locomotion on hipbone trabecular microarchitecture. This study found a weak functional signal detected in differences in bone volume fraction and the degree of anisotropy across certain pre-assigned locomotor categories, while confirming previously recognized allometric scaling trends reported for other mammalian samples based on the femur. Within primates, a more anisotropic pattern was observed for quadrupedal species attributed to their repetitive loading regimes and stereotypical limb excursions, while isotropic values were revealed for taxa utilizing more varied arboreal repertoires. Humans, despite a frequent and predictable loading environment associated with their use of bipedalism, showed relatively isotropic values. This study highlights the confounding factors that influence trabecular microarchitecture and consequently limit its utility as a method for investigating locomotor adaptation.
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Sacrum morphology supports taxonomic heterogeneity of "Australopithecus africanus" at Sterkfontein Member 4. Commun Biol 2021; 4:347. [PMID: 33731844 PMCID: PMC7969745 DOI: 10.1038/s42003-021-01850-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 02/12/2021] [Indexed: 12/14/2022] Open
Abstract
The presence of multiple Australopithecus species at Sterkfontein Member 4, South Africa (2.07–2.61 Ma), is highly contentious, and quantitative assessments of craniodental and postcranial variability remain inconclusive. Using geometric morphometrics, we compared the sacrum of the small-bodied, presumed female subadult Australopithecus africanus skeleton Sts 14 to the large, alleged male adult StW 431 against a geographically diverse sample of modern humans, and two species of Pan, Gorilla, and Pongo. The probabilities of sampling morphologies as distinct as Sts 14 and StW 431 from a single species ranged from 1.3 to 2.5% for the human sample, and from 0.0 to 4.5% for the great apes, depending on the species and the analysis. Sexual dimorphism and developmental or geologic age could not adequately explain the differences between StW 431 and Sts 14, suggesting that they are unlikely to be conspecific. This supports earlier claims of taxonomic heterogeneity at Sterkfontein Member 4. Fornai et al. present a geometric morphometric study of the sacrum in two alleged Australopithecus africanus specimens from Sterkfontein Member 4, South Africa. By comparing the two fossil hominins to a diverse sample of modern humans and great apes, the authors conclude that the observed morphological differences are unlikely to occur within a single species, supporting earlier claims of taxonomic heterogeneity within the Australopithecus africanus hypodigm.
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