TY - JOUR
T1 - The SKX 1084 hominin patella from Swartkrans Member 2, South Africa
T2 - An integrated analysis of its outer morphology and inner structure
AU - Cazenave, Marine
AU - Oettlé, Anna
AU - Thackeray, John Francis
AU - Nakatsukasa, Masato
AU - de Beer, Frikkie
AU - Hoffman, Jakobus
AU - Macchiarelli, Roberto
N1 - Funding Information:
For access to fossil and comparative materials, we are grateful to the curators of the Ditsong National Museum of Natural History, Pretoria; the Pretoria Bone Collection at the Department of Anatomy of the University of Pretoria; and the Evolutionary Studies Institute at the University of the Witwatersrand. For the realization at the ICTP Multidisciplinary Lab. of Trieste of scans of comparative human material stored at the National Museum “L. Pigorini” of Rome, we acknowledge F. Bernardini, L. Bondioli, C. Tuniz, and C. Zanolli; we also acknowledge M. Nakamura (Kyoto) and Y. Shintaku (Inuyama) for access to the Pan specimens used in this study. For their kind contribution during various analytical phases (including the intra- and inter-observer tests), we are especially grateful to A. Beaudet (Johannesburg) and C. Zanolli (Toulouse). For collaboration and discussion, we also thank L. Bam (Pelindaba), J. Braga (Toulouse & Johannesburg), L. Bruxelles (Toulouse and Johannesburg), R.J. Clarke (Johannesburg), J. Dumoncel (Toulouse), J. Heaton (Birmingham and Johannesburg), T. Jashashvili (Johannesburg), L. Kgasi (Pretoria), K. Kuman (Johannesburg), D. Marchi (Pisa), T. Pickering (Madison and Johannesburg), S. Potze (Pretoria), B. Zipfel (Johannesburg). The comments from two reviewers significantly enhanced the quality of the first version of this study. We acknowledge the DST-NRF for the financial support (Grant # UID23456) to establish the MIXRAD micro-focus X-ray tomography facility at Necsa. M.C. is funded by the European Commission (EACEA), Erasmus Mundus programme, AESOP and AESOP+ consortia coordinated by J. Braga (Toulouse).
Funding Information:
For access to fossil and comparative materials, we are grateful to the curators of the Ditsong National Museum of Natural History, Pretoria; the Pretoria Bone Collection at the Department of Anatomy of the University of Pretoria; and the Evolutionary Studies Institute at the University of the Witwatersrand. For the realization at the ICTP Multidisciplinary Lab. of Trieste of scans of comparative human material stored at the National Museum ?L. Pigorini? of Rome, we acknowledge F. Bernardini, L. Bondioli, C. Tuniz, and C. Zanolli; we also acknowledge M. Nakamura (Kyoto) and Y. Shintaku (Inuyama) for access to the Pan specimens used in this study. For their kind contribution during various analytical phases (including the intra- and inter-observer tests), we are especially grateful to A. Beaudet (Johannesburg) and C. Zanolli (Toulouse). For collaboration and discussion, we also thank L. Bam (Pelindaba), J. Braga (Toulouse & Johannesburg), L. Bruxelles (Toulouse and Johannesburg), R.J. Clarke (Johannesburg), J. Dumoncel (Toulouse), J. Heaton (Birmingham and Johannesburg), T. Jashashvili (Johannesburg), L. Kgasi (Pretoria), K. Kuman (Johannesburg), D. Marchi (Pisa), T. Pickering (Madison and Johannesburg), S. Potze (Pretoria), B. Zipfel (Johannesburg). The comments from two reviewers significantly enhanced the quality of the first version of this study. We acknowledge the DST-NRF for the financial support (Grant # UID23456) to establish the MIXRAD micro-focus X-ray tomography facility at Necsa. M.C. is funded by the European Commission (EACEA), Erasmus Mundus programme, AESOP and AESOP+ consortia coordinated by J. Braga (Toulouse).
Publisher Copyright:
© 2018
PY - 2019/3
Y1 - 2019/3
N2 - SKX 1084 is an isolated partial patella from Swartkrans Member 2, South Africa, attributed to a small-bodied Paranthropus robustus. This study provides complementary information on its outer conformation and, for the first time for a fossil hominin patella, documents its inner structure in the perspective of adding biomechanically-related evidence to clarify its identity. We used X-ray micro-tomography to investigate SKX 1084 and to extract homologous information from a sample of 12 recent human, one Neanderthal, and two adult Pan, patellae. We used geometric morphometrics to compare the outer equatorial contours. In SKX 1084, we identified two cancellous bony spots suitable for textural assessment (trabecular bone volume fraction, trabecular thickness, degree of anisotropy), and two related virtual slices for measuring the maximum cortico-trabecular thickness (CTT) of the articular surface. SKX 1084 shows a more complex articular shape than that for Pan, but still simpler than typical in Homo sapiens. At all sites, its CTT is thinner compared to Pan and approaches the condition in humans. This is also true for the expanded volume of the cancellous network. However, at both investigated spots, SKX 1084 is systematically intermediate between Homo and Pan for trabecular bone volume fraction and trabecular thickness, a pattern already shown in previous analyses on other Paranthropus postcranial remains. In the absence of any structural signal from patellae unambiguously sampling Paranthropus, as well as of comparable evidence extracted from specimens representing early Homo, our results do not allow rejection of the original taxonomic attribution of SKX 1084.
AB - SKX 1084 is an isolated partial patella from Swartkrans Member 2, South Africa, attributed to a small-bodied Paranthropus robustus. This study provides complementary information on its outer conformation and, for the first time for a fossil hominin patella, documents its inner structure in the perspective of adding biomechanically-related evidence to clarify its identity. We used X-ray micro-tomography to investigate SKX 1084 and to extract homologous information from a sample of 12 recent human, one Neanderthal, and two adult Pan, patellae. We used geometric morphometrics to compare the outer equatorial contours. In SKX 1084, we identified two cancellous bony spots suitable for textural assessment (trabecular bone volume fraction, trabecular thickness, degree of anisotropy), and two related virtual slices for measuring the maximum cortico-trabecular thickness (CTT) of the articular surface. SKX 1084 shows a more complex articular shape than that for Pan, but still simpler than typical in Homo sapiens. At all sites, its CTT is thinner compared to Pan and approaches the condition in humans. This is also true for the expanded volume of the cancellous network. However, at both investigated spots, SKX 1084 is systematically intermediate between Homo and Pan for trabecular bone volume fraction and trabecular thickness, a pattern already shown in previous analyses on other Paranthropus postcranial remains. In the absence of any structural signal from patellae unambiguously sampling Paranthropus, as well as of comparable evidence extracted from specimens representing early Homo, our results do not allow rejection of the original taxonomic attribution of SKX 1084.
KW - Cancellous network
KW - Cortical bone
KW - Fossil hominins
KW - Knee joint
KW - X-ray micro-tomography
UR - http://www.scopus.com/inward/record.url?scp=85057001477&partnerID=8YFLogxK
U2 - 10.1016/j.crpv.2018.06.002
DO - 10.1016/j.crpv.2018.06.002
M3 - Article
AN - SCOPUS:85057001477
SN - 1631-0683
VL - 18
SP - 223
EP - 235
JO - Comptes Rendus - Palevol
JF - Comptes Rendus - Palevol
IS - 2
ER -