1
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Villamil CI, Middleton ER. Conserved patterns and locomotor-related evolutionary constraints in the hominoid vertebral column. J Hum Evol 2024; 190:103528. [PMID: 38579429 DOI: 10.1016/j.jhevol.2024.103528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 03/13/2024] [Accepted: 03/14/2024] [Indexed: 04/07/2024]
Abstract
The evolution of the hominoid lineage is characterized by pervasive homoplasy, notably in regions such as the vertebral column, which plays a central role in body support and locomotion. Few isolated and fewer associated vertebrae are known for most fossil hominoid taxa, but identified specimens indicate potentially high levels of convergence in terms of both form and number. Homoplasy thus complicates attempts to identify the anatomy of the last common ancestor of hominins and other taxa and stymies reconstructions of evolutionary scenarios. One way to clarify the role of homoplasy is by investigating constraints via phenotypic integration, which assesses covariation among traits, shapes evolutionary pathways, and itself evolves in response to selection. We assessed phenotypic integration and evolvability across the subaxial (cervical, thoracic, lumbar, sacral) vertebral column of macaques (n = 96), gibbons (n = 77), chimpanzees (n = 92), and modern humans (n = 151). We found a mid-cervical cluster that may have shifted cranially in hominoids, a persistent thoracic cluster that is most marked in chimpanzees, and an expanded lumbosacral cluster in hominoids that is most expanded in gibbons. Our results highlight the highly conserved nature of the vertebral column. Taxa appear to exploit existing patterns of integration and ontogenetic processes to shift, expand, or reduce cluster boundaries. Gibbons appear to be the most highly derived taxon in our sample, possibly in response to their highly specialized locomotion.
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Affiliation(s)
- Catalina I Villamil
- School of Chiropractic, Universidad Central del Caribe, Puerto Rico, PO Box 60327, Bayamón, USA.
| | - Emily R Middleton
- Department of Anthropology, University of Wisconsin-Milwaukee, 3413 N. Downer Ave., Sabin Hall 390, Milwaukee, WI, USA
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2
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Vanhoof MJM, Croquet B, De Groote I, Vereecke EE. Principal component and linear discriminant analyses for the classification of hominoid primate specimens based on bone shape data. ROYAL SOCIETY OPEN SCIENCE 2023; 10:230950. [PMID: 37736524 PMCID: PMC10509576 DOI: 10.1098/rsos.230950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 09/01/2023] [Indexed: 09/23/2023]
Abstract
In this study, we tested the hypothesis that machine learning methods can accurately classify extant primates based on triquetrum shape data. We then used this classification tool to observe the affinities between extant primates and fossil hominoids. We assessed the discrimination accuracy for an unsupervised and supervised learning pipeline, i.e. with principal component analysis (PCA) and linear discriminant analysis (LDA) feature extraction, when tasked with the classification of extant primates. The trained algorithm is used to classify a sample of known fossil hominoids. For the visualization, PCA and uniform manifold approximation and projection (UMAP) are used. The results show that the discriminant function correctly classified the extant specimens with an F1-score of 0.90 for both PCA and LDA. In addition, the classification of fossil hominoids reflects taxonomy and locomotor behaviour reported in literature. This classification based on shape data using PCA and LDA is a powerful tool that can discriminate between the triquetrum shape of extant primates with high accuracy and quantitatively compare fossil and extant morphology. It can be used to support taxonomic differentiation and aid the further interpretation of fossil remains. Further testing is necessary by including other bones and more species and specimens per species extinct primates.
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Affiliation(s)
- Marie J. M. Vanhoof
- Department of Development & Regeneration, Biomedical Sciences Group, KU Leuven Campus Kulak, Kortrijk, Belgium
| | - Balder Croquet
- Medical Imaging Research Center, UZ Leuven, Leuven, Belgium
- Department of Electrical Engineering, ESAT/PSI, KU Leuven, Leuven, Belgium
| | - Isabelle De Groote
- Department of Archaeology, Ghent University, Ghent, Belgium
- Research Centre in Evolutionary Anthropology and Paleoecology, Liverpool John Moores University, Liverpool L3 3AF, UK
| | - Evie E. Vereecke
- Department of Development & Regeneration, Biomedical Sciences Group, KU Leuven Campus Kulak, Kortrijk, Belgium
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3
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Spear JK, Grabowski M, Sekhavati Y, Costa CE, Goldstein DM, Petrullo LA, Peterson AL, Lee AB, Shattuck MR, Gómez-Olivencia A, Williams SA. Evolution of vertebral numbers in primates, with a focus on hominoids and the last common ancestor of hominins and panins. J Hum Evol 2023; 179:103359. [PMID: 37099927 DOI: 10.1016/j.jhevol.2023.103359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 03/14/2023] [Accepted: 03/14/2023] [Indexed: 04/28/2023]
Abstract
The primate vertebral column has been extensively studied, with a particular focus on hominoid primates and the last common ancestor of humans and chimpanzees. The number of vertebrae in hominoids-up to and including the last common ancestor of humans and chimpanzees-is subject to considerable debate. However, few formal ancestral state reconstructions exist, and none include a broad sample of primates or account for the correlated evolution of the vertebral column. Here, we conduct an ancestral state reconstruction using a model of evolution that accounts for both homeotic (changes of one type of vertebra to another) and meristic (addition or loss of a vertebra) changes. Our results suggest that ancestral primates were characterized by 29 precaudal vertebrae, with the most common formula being seven cervical, 13 thoracic, six lumbar, and three sacral vertebrae. Extant hominoids evolved tail loss and a reduced lumbar column via sacralization (homeotic transition at the last lumbar vertebra). Our results also indicate that the ancestral hylobatid had seven cervical, 13 thoracic, five lumbar, and four sacral vertebrae, and the ancestral hominid had seven cervical, 13 thoracic, four lumbar, and five sacral vertebrae. The last common ancestor of humans and chimpanzees likely either retained this ancestral hominid formula or was characterized by an additional sacral vertebra, possibly acquired through a homeotic shift at the sacrococcygeal border. Our results support the 'short-back' model of hominin vertebral evolution, which postulates that hominins evolved from an ancestor with an African ape-like numerical composition of the vertebral column.
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Affiliation(s)
- Jeffrey K Spear
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA; New York Consortium in Evolutionary Primatology, New York, NY, USA.
| | - Mark Grabowski
- Research Centre in Evolutionary Anthropology and Paleoecology, Liverpool John Moores University, Liverpool, UK; Department of Biosciences, Centre for Ecological and Evolutionary Synthesis, University of Oslo, Oslo, Norway
| | - Yeganeh Sekhavati
- Department of Anthropology, Washington University in St. Louis, St. Louis, MO, USA
| | - Christina E Costa
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA; New York Consortium in Evolutionary Primatology, New York, NY, USA
| | - Deanna M Goldstein
- Department of Anatomical Sciences, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY, USA
| | - Lauren A Petrullo
- Department of Psychology, University of Michigan, Ann Arbor, MI, USA
| | - Amy L Peterson
- Smithsonian Institution, National Museum of Natural History, Washington DC, USA
| | - Amanda B Lee
- Data Scientist, Jellyfish, Suite 3033, 220 N Green St, Chicago, IL, USA
| | | | - Asier Gómez-Olivencia
- Departamento de Geología, Facultad de Ciencia y Tecnología, Universidad Del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), Barrio Sarriena S/n, 48940 Bilbao, Spain; Sociedad de Ciencias Aranzadi, Zorroagagaina 11, 20014 Donostia-San Sebastián, Spain; Centro UCM-ISCIII de Investigación Sobre Evolución y Comportamiento Humanos, Avda. Monforte de Lemos 5 (Pabellón 14), 28029 Madrid, Spain
| | - Scott A Williams
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, NY, USA; New York Consortium in Evolutionary Primatology, New York, NY, USA
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4
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Mongle CS, Strait DS, Grine FE. An updated analysis of hominin phylogeny with an emphasis on re-evaluating the phylogenetic relationships of Australopithecus sediba. J Hum Evol 2023; 175:103311. [PMID: 36706599 DOI: 10.1016/j.jhevol.2022.103311] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 12/16/2022] [Accepted: 12/16/2022] [Indexed: 01/26/2023]
Abstract
The discovery and description of Australopithecus sediba has reignited the debate over the evolutionary history of the australopiths and the genus Homo. It has been suggested that A. sediba may be an ancestor of Homo because it possesses a mosaic of derived Homo-like and primitive australopith-like traits. However, an alternative hypothesis proposes that the majority of the purported Homo-like craniodental characters can be attributed to the juvenile status of the type specimen, MH1. We conducted an independent character assessment of the craniodental morphology of A. sediba, with particular emphasis on evaluating whether the ontogenetic status of MH1 may have affected its purported Homo-like characteristics. In doing so, we have also expanded fossil hypodigms to incorporate the new Australopithecus anamensis cranium from Woranso-Mille (MRD-VP-1/1), as well as recently described Paranthropus robustus cranial remains from Drimolen (DNH 7, DNH 155). Morphological character data were analyzed using both standard parsimony and Bayesian techniques. In addition, we conducted a series of Bayesian analyses constrained to evaluate the hypothesis that Australopithecus africanus and A. sediba are sister taxa. Based on the results of the parsimony and Bayesian analyses, we could not reject the hypothesis that A. sediba shares its closest phylogenetic affinities with the genus Homo. Therefore, based on currently available craniodental evidence, we conclude that A. sediba is plausibly the terminal end of a lineage that shared a common ancestor with the earliest representatives of Homo. We caution, however, that the discovery of new A. sediba fossils preserving adult cranial morphology or the inclusion of postcranial characters may ultimately necessitate a re-evaluation of this hypothesis.
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Affiliation(s)
- Carrie S Mongle
- Department of Anthropology, Stony Brook University, Stony Brook, NY 11794-4364, USA; Division of Anthropology, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024-5192, USA; Turkana Basin Institute, Stony Brook University, Stony Brook, NY 11794-4364, USA.
| | - David S Strait
- Department of Anthropology, Washington University in St. Louis, 1 Brookings Dr, St. Louis, MO 63130, USA; Palaeo-Research Institute, University of Johannesburg, Cottesloe, Johannesburg, 2092, South Africa
| | - Frederick E Grine
- Department of Anthropology, Stony Brook University, Stony Brook, NY 11794-4364, USA; Department of Anatomical Sciences, Stony Brook University, Stony Brook, NY 11794-4364, USA
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5
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Cazenave M, Kivell TL. Challenges and perspectives on functional interpretations of australopith postcrania and the reconstruction of hominin locomotion. J Hum Evol 2023; 175:103304. [PMID: 36563461 DOI: 10.1016/j.jhevol.2022.103304] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 11/15/2022] [Accepted: 11/16/2022] [Indexed: 12/24/2022]
Abstract
In 1994, Hunt published the 'postural feeding hypothesis'-a seminal paper on the origins of hominin bipedalism-founded on the detailed study of chimpanzee positional behavior and the functional inferences derived from the upper and lower limb morphology of the Australopithecus afarensis A.L. 288-1 partial skeleton. Hunt proposed a model for understanding the potential selective pressures on hominins, made robust, testable predictions based on Au. afarensis functional morphology, and presented a hypothesis that aimed to explain the dual functional signals of the Au. afarensis and, more generally, early hominin postcranium. Here we synthesize what we have learned about Au. afarensis functional morphology and the dual functional signals of two new australopith discoveries with relatively complete skeletons (Australopithecus sediba and StW 573 'Australopithecus prometheus'). We follow this with a discussion of three research approaches that have been developed for the purpose of drawing behavioral inferences in early hominins: (1) developments in the study of extant apes as models for understanding hominin origins; (2) novel and continued developments to quantify bipedal gait and locomotor economy in extant primates to infer the locomotor costs from the anatomy of fossil taxa; and (3) novel developments in the study of internal bone structure to extract functional signals from fossil remains. In conclusion of this review, we discuss some of the inherent challenges of the approaches and methodologies adopted to reconstruct the locomotor modes and behavioral repertoires in extinct primate taxa, and notably the assessment of habitual terrestrial bipedalism in early hominins.
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Affiliation(s)
- Marine Cazenave
- Division of Anthropology, American Museum of Natural History, New York, USA; Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK; Department of Anatomy, Faculty of Health Sciences, University of Pretoria, South Africa.
| | - Tracy L Kivell
- Skeletal Biology Research Centre, School of Anthropology and Conservation, University of Kent, Canterbury, UK; Centre for the Exploration of the Deep Human Journey, University of the Witwatersrand, Johannesburg, South Africa
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6
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Williams SA, Prang TC, Meyer MR, Nalley TK, Van Der Merwe R, Yelverton C, García-Martínez D, Russo GA, Ostrofsky KR, Spear J, Eyre J, Grabowski M, Nalla S, Bastir M, Schmid P, Churchill SE, Berger LR. New fossils of Australopithecus sediba reveal a nearly complete lower back. eLife 2021; 10:70447. [PMID: 34812141 PMCID: PMC8610421 DOI: 10.7554/elife.70447] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 10/19/2021] [Indexed: 01/16/2023] Open
Abstract
Adaptations of the lower back to bipedalism are frequently discussed but infrequently demonstrated in early fossil hominins. Newly discovered lumbar vertebrae contribute to a near-complete lower back of Malapa Hominin 2 (MH2), offering additional insights into posture and locomotion in Australopithecus sediba. We show that MH2 possessed a lower back consistent with lumbar lordosis and other adaptations to bipedalism, including an increase in the width of intervertebral articular facets from the upper to lower lumbar column (‘pyramidal configuration’). These results contrast with some recent work on lordosis in fossil hominins, where MH2 was argued to demonstrate no appreciable lordosis (‘hypolordosis’) similar to Neandertals. Our three-dimensional geometric morphometric (3D GM) analyses show that MH2’s nearly complete middle lumbar vertebra is human-like in overall shape but its vertebral body is somewhat intermediate in shape between modern humans and great apes. Additionally, it bears long, cranially and ventrally oriented costal (transverse) processes, implying powerful trunk musculature. We interpret this combination of features to indicate that A. sediba used its lower back in both bipedal and arboreal positional behaviors, as previously suggested based on multiple lines of evidence from other parts of the skeleton and reconstructed paleobiology of A. sediba. One of the defining features of humans is our ability to walk comfortably on two legs. To achieve this, our skeletons have evolved certain physical characteristics. For example, the lower part of the human spine has a forward curve that supports an upright posture; whereas the lower backs of chimpanzees and other apes – which walk around on four limbs and spend much of their time in trees – lack this curvature. Studying the fossilized back bones of ancient human remains can help us to understand how we evolved these features, and whether our ancestors moved in a similar way. Australopithecus sediba was a close-relative of modern humans that lived about two million years ago. In 2008, fossils from an adult female were discovered at a cave site in South Africa called Malapa. However, the fossils of the lower back region were incomplete, so it was unclear whether the female – referred to as Malapa Hominin 2 (MH2) – had a forward-curving spine and other adaptations needed to walk on two legs. Here, Williams et al. report the discovery of new A. sediba fossils from Malapa. The new fossils are mainly bones from the lower back, and they fit together with the previously discovered MH2 fossils, providing a nearly complete lower spine. Analysis of the fossils suggested that MH2 would have had an upright posture and comfortably walked on two legs, and the curvature of their lower back was similar to modern females. However, other aspects of the bones’ shape suggest that as well as walking, A. sediba probably spent a significant amount of time climbing in trees. The findings of Williams et al. provide new insights in to our evolutionary history, and ultimately, our place in the natural world around us. Our lower back is prone to injury and pain associated with posture, pregnancy and exercise (or lack thereof). Therefore, understanding how the lower back evolved may help us to learn how to prevent injuries and maintain a healthy back.
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Affiliation(s)
- Scott A Williams
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, United States.,New York Consortium in Evolutionary Primatology, New York, United States.,Centre for the Exploration of the Deep Human Journey, University of the Witwatersrand, Johannesburg, South Africa.,Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
| | - Thomas Cody Prang
- Department of Anthropology, Texas A&M University, College Station, United States
| | - Marc R Meyer
- Department of Anthropology, Chaffey College, Rancho Cucamonga, United States
| | - Thierra K Nalley
- Western University of Health Sciences, College of Osteopathic Medicine of the Pacific, Department of Medical Anatomical Sciences, Pomona, United States
| | - Renier Van Der Merwe
- Centre for the Exploration of the Deep Human Journey, University of the Witwatersrand, Johannesburg, South Africa
| | - Christopher Yelverton
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa.,Department of Chiropractic, Faculty of Health Sciences, University of Johannesburg, Johannesburg, South Africa
| | - Daniel García-Martínez
- Centre for the Exploration of the Deep Human Journey, University of the Witwatersrand, Johannesburg, South Africa.,Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), Burgos, Spain.,Departamento de Biodiversidad, Ecología y Evolución, Universidad Complutense de Madrid (UCM), Madrid, Spain
| | - Gabrielle A Russo
- Department of Anthropology, Stony Brook University, Stony Brook, United States
| | - Kelly R Ostrofsky
- Department of Anatomy, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, United States
| | - Jeffrey Spear
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, United States.,New York Consortium in Evolutionary Primatology, New York, United States
| | - Jennifer Eyre
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, United States.,Department of Anthropology, Bryn Mawr College, Bryn Mawr, United States
| | - Mark Grabowski
- Research Centre in Evolutionary Anthropology and Palaeoecology, Liverpool John Moores University, Liverpool, United Kingdom
| | - Shahed Nalla
- Centre for the Exploration of the Deep Human Journey, University of the Witwatersrand, Johannesburg, South Africa.,Department of Human Anatomy and Physiology, Faculty of Health Sciences, University of Johannesburg, Johannesburg, South Africa
| | - Markus Bastir
- Centre for the Exploration of the Deep Human Journey, University of the Witwatersrand, Johannesburg, South Africa.,Departamento de Paleobiología, Museo Nacional de Ciencias Naturales (CSIC), Madrid, Spain
| | - Peter Schmid
- Centre for the Exploration of the Deep Human Journey, University of the Witwatersrand, Johannesburg, South Africa.,Anthropological Institute and Museum, University of Zurich, Zurich, Switzerland
| | - Steven E Churchill
- Centre for the Exploration of the Deep Human Journey, University of the Witwatersrand, Johannesburg, South Africa.,Department of Evolutionary Anthropology, Duke University, Durham, United States
| | - Lee R Berger
- Centre for the Exploration of the Deep Human Journey, University of the Witwatersrand, Johannesburg, South Africa
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7
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Williams SA, Pilbeam D. Homeotic change in segment identity derives the human vertebral formula from a chimpanzee-like one. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2021; 176:283-294. [PMID: 34227681 DOI: 10.1002/ajpa.24356] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 02/12/2021] [Accepted: 06/07/2021] [Indexed: 01/10/2023]
Abstract
OBJECTIVES One of the most contentious issues in paleoanthropology is the nature of the last common ancestor of humans and our closest living relatives, chimpanzees and bonobos (panins). The numerical composition of the vertebral column has featured prominently, with multiple models predicting distinct patterns of evolution and contexts from which bipedalism evolved. Here, we study total numbers of vertebrae from a large sample of hominoids to quantify variation in and patterns of regional and total numbers of vertebrae in hominoids. MATERIALS AND METHODS We compile and study a large sample (N = 893) of hominoid vertebral formulae (numbers of cervical, thoracic, lumbar, sacral, caudal segments in each specimen) and analyze full vertebral formulae, total numbers of vertebrae, and super-regional numbers of vertebrae: presacral (cervical, thoracic, lumbar) vertebrae and sacrococcygeal vertebrae. We quantify within- and between-taxon variation using heterogeneity and similarity measures derived from population genetics. RESULTS We find that humans are most similar to African apes in total and super-regional numbers of vertebrae. Additionally, our analyses demonstrate that selection for bipedalism reduced variation in numbers of vertebrae relative to other hominoids. DISCUSSION The only proposed ancestral vertebral configuration for the last common ancestor of hominins and panins that is consistent with our results is the modal formula demonstrated by chimpanzees and bonobos (7 cervical-13 thoracic-4 lumbar-6 sacral-3 coccygeal). Hox gene expression boundaries suggest that a rostral shift in Hox10/Hox11-mediated complexes could produce the human modal formula from the proposal ancestral and panin modal formula.
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Affiliation(s)
- Scott A Williams
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, USA.,New York Consortium in Evolutionary Primatology, New York, USA
| | - David Pilbeam
- Department of Human Evolutionary Biology, Harvard University, Cambridge, USA
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8
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Machnicki AL, Reno PL. Great apes and humans evolved from a long-backed ancestor. J Hum Evol 2020; 144:102791. [DOI: 10.1016/j.jhevol.2020.102791] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 03/20/2020] [Accepted: 03/23/2020] [Indexed: 12/20/2022]
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Plomp KA, Dobney K, Weston DA, Strand Viðarsdóttir U, Collard M. 3D shape analyses of extant primate and fossil hominin vertebrae support the ancestral shape hypothesis for intervertebral disc herniation. BMC Evol Biol 2019; 19:226. [PMID: 31842740 PMCID: PMC6916256 DOI: 10.1186/s12862-019-1550-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 11/29/2019] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Recently we proposed an evolutionary explanation for a spinal pathology that afflicts many people, intervertebral disc herniation (Plomp et al. [2015] BMC Evolutionary Biology 15, 68). Using 2D data, we found that the bodies and pedicles of lower vertebrae of pathological humans were more similar in shape to those of chimpanzees than were those of healthy humans. Based on this, we hypothesized that some individuals are more prone to intervertebral disc herniation because their vertebrae exhibit ancestral traits and therefore are less well adapted for the stresses associated with bipedalism. Here, we report a study in which we tested this "Ancestral Shape Hypothesis" with 3D data from the last two thoracic and first lumbar vertebrae of pathological Homo sapiens, healthy H. sapiens, Pan troglodytes, and several extinct hominins. RESULTS We found that the pathological and healthy H. sapiens vertebrae differed significantly in shape, and that the pathological H. sapiens vertebrae were closer in shape to the P. troglodytes vertebrae than were the healthy H. sapiens vertebrae. Additionally, we found that the pathological human vertebrae were generally more similar in shape to the vertebrae of the extinct hominins than were the healthy H. sapiens vertebrae. These results are consistent with the predictions of the Ancestral Shape Hypothesis. Several vertebral traits were associated with disc herniation, including a vertebral body that is both more circular and more ventrally wedged, relatively short pedicles and laminae, relatively long, more cranio-laterally projecting transverse processes, and relatively long, cranially-oriented spinous processes. We found that there are biomechanical and comparative anatomical reasons for suspecting that all of these traits are capable of predisposing individuals to intervertebral disc herniation. CONCLUSIONS The results of the present study add weight to the hypothesis that intervertebral disc herniation in H. sapiens is connected with vertebral shape. Specifically, they suggest that individuals whose vertebrae are towards the ancestral end of the range of shape variation within H. sapiens have a greater propensity to develop the condition than other individuals. More generally, the study shows that evolutionary thinking has the potential to shed new light on human skeletal pathologies.
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Affiliation(s)
- Kimberly A Plomp
- Department of Archaeology, Classics and Egyptology, University of Liverpool, 14 Abercromby Square, Liverpool, L69 7WZ, UK.,Department of Archaeology, Simon Fraser University, 8888 University Dr, Burnaby, BC, V5A 1S6, Canada
| | - Keith Dobney
- Department of Archaeology, Classics and Egyptology, University of Liverpool, 14 Abercromby Square, Liverpool, L69 7WZ, UK.,Department of Archaeology, Simon Fraser University, 8888 University Dr, Burnaby, BC, V5A 1S6, Canada.,Department of Archaeology, School of Geosciences, University of Aberdeen, St Mary's, Elphinstone Road, Scotland, UK, AB24 3UF, Aberdeen
| | - Darlene A Weston
- Department of Anthropology, University of British Columbia, 6303 NW Marine Drive, Vancouver, BC, V6T 1Z1, Canada
| | - Una Strand Viðarsdóttir
- Biomedical Center, University of Iceland, Læknagarður, Vatnsmýrarvegi 16, 101, Reykjavík, Iceland
| | - Mark Collard
- Department of Archaeology, Simon Fraser University, 8888 University Dr, Burnaby, BC, V5A 1S6, Canada.
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10
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Plomp K, Viðarsdóttir US, Dobney K, Weston D, Collard M. Potential adaptations for bipedalism in the thoracic and lumbar vertebrae of Homo sapiens: A 3D comparative analysis. J Hum Evol 2019; 137:102693. [PMID: 31711026 DOI: 10.1016/j.jhevol.2019.102693] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 10/12/2019] [Accepted: 10/12/2019] [Indexed: 10/25/2022]
Abstract
A number of putative adaptations for bipedalism have been identified in the hominin spine. However, it is possible that some have been overlooked because only a few studies have used 3D and these studies have focused on cervical vertebrae. With this in mind, we used geometric morphometric techniques to compare the 3D shapes of three thoracic and two lumbar vertebrae of Homo sapiens, Pan troglodytes, Gorilla gorilla, and Pongo pygmaeus. The study had two goals. One was to confirm the existence of traits previously reported to distinguish the thoracic and lumbar vertebrae of H. sapiens from those of the great apes. The other was to, if possible, identify hitherto undescribed traits that differentiate H. sapiens thoracic and lumbar vertebrae from those of the great apes. Both goals were accomplished. Our analyses not only substantiated a number of traits that have previously been discussed in the literature but also identified four traits that have not been described before: (1) dorsoventrally shorter pedicles in the upper thoracic vertebrae; (2) dorsoventrally longer laminae in all five of the vertebrae examined; (3) longer transverse processes in the upper thoracic vertebrae; and (4) craniocaudally 'pinched' spinous process tips in all of the vertebrae examined. A review of the biomechanical literature suggests that most of the traits highlighted in our analyses can be plausibly linked to bipedalism, including three of the four new ones. As such, the present study not only sheds further light on the differences between the spines of H. sapiens and great apes but also enhances our understanding of how the shift to bipedalism affected the hominin vertebral column.
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Affiliation(s)
- Kimberly Plomp
- Department of Archaeology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada; Department of Archaeology, Classics and Egyptology, University of Liverpool, 14 Abercromby Square, Liverpool, L69 7WZ, UK.
| | - Una Strand Viðarsdóttir
- Biomedical Center, University of Iceland, Læknagarður, Vatnsmýrarvegi 16, 101 Reykjavík, Iceland
| | - Keith Dobney
- Department of Archaeology, Classics and Egyptology, University of Liverpool, 14 Abercromby Square, Liverpool, L69 7WZ, UK
| | - Darlene Weston
- Department of Anthropology, University of British Columbia, 6303 NW Marine Drive, Vancouver, BC V6T 1Z1, Canada
| | - Mark Collard
- Department of Archaeology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
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11
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Selby MS, Gillette A, Raval Y, Taufiq M, Sampson MJ. Modern Medical Consequences of the Ancient Evolution of a Long, Flexible Lumbar Spine. J Osteopath Med 2019; 119:622-630. [PMID: 31449308 DOI: 10.7556/jaoa.2019.105] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Modern human bipedality is unique and requires lumbar lordosis, whereas chimpanzees, our closest relatives, have short lumbar spines rendering them incapable of lordosis. To facilitate lordosis, humans have longer lumbar spines, greater lumbosacral angle, dorsally wedged lumbar vertebral bodies, and lumbar zygapophyseal joints with both increasingly coronal orientation and further caudal interfacet distances. These features limit modern lower lumbar spine and lumbosacral joint ailments, albeit imperfectly. The more coronal zygapophyseal orientation limits spondylolisthesis, while increasing interfacet distance may limit spondylolysis. Common back pain, particularly in people who are obese or pregnant, may result from increased lumbar lordosis, causing additional mass transfer through the zygapophyseal joints rather than vertebral bodies. Reduction in lumbar lordosis, such as in flatback syndrome from decreased lumbosacral angle, can also cause back pain. Human lumbar lordosis is necessary for placing the trunk atop the pelvis and presents a balancing act not required of our closest primate relatives.
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12
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Meyer MR, Williams SA. Earliest axial fossils from the genus Australopithecus. J Hum Evol 2019; 132:189-214. [PMID: 31203847 DOI: 10.1016/j.jhevol.2019.05.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 05/05/2019] [Accepted: 05/06/2019] [Indexed: 11/19/2022]
Abstract
Australopitheus anamensis fossils demonstrate that craniodentally and postcranially the taxon was more primitive than its evolutionary successor Australopithecus afarensis. Postcranial evidence suggests habitual bipedality combined with primitive upper limbs and an inferred significant arboreal adaptation. Here we report on A. anamensis fossils from the Assa Issie locality in Ethiopia's Middle Awash area dated to ∼4.2 Ma, constituting the oldest known Australopithecus axial remains. Because the spine is the interface between major body segments, these fossils can be informative on the adaptation, behavior and our evolutionary understanding of A. anamensis. The atlas, or first cervical vertebra (C1), is similar in size to Homo sapiens, with synapomorphies in the articular facets and transverse processes. Absence of a retroglenoid tubercle suggests that, like humans, A. anamensis lacked the atlantoclavicularis muscle, resulting in reduced capacity for climbing relative to the great apes. The retroflexed C2 odontoid process and long C6 spinous process are reciprocates of facial prognathism, a long clivus and retroflexed foramen magnum, rather than indications of locomotor or postural behaviors. The T1 is derived in shape and size as in Homo with an enlarged vertebral body epiphyseal surfaces for mitigating the high-magnitude compressive loads of full-time bipedality. The full costal facet is unlike the extant great ape demifacet pattern and represents the oldest evidence for the derived univertebral pattern in hominins. These fossils augment other lines of evidence in A. anamensis indicating habitual bipedality despite some plesiomorphic vertebral traits related to craniofacial morphology independent of locomotor or postural behaviors (i.e., a long clivus and a retroflexed foramen magnum). Yet in contrast to craniodental lines of evidence, some aspects of vertebral morphology in A. anamensis appear more derived than its descendant A. afarensis.
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Affiliation(s)
- Marc R Meyer
- Department of Anthropology, Chaffey College, Rancho Cucamonga, CA, 91737, USA.
| | - Scott A Williams
- Center for the Study of Human Origins, Department of Anthropology, New York University, 25 Waverly Place, New York, NY, 10003, USA; New York Consortium in Evolutionary Primatology, New York, NY, 10024, USA
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13
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Williams SA, Spear JK, Petrullo L, Goldstein DM, Lee AB, Peterson AL, Miano DA, Kaczmarek EB, Shattuck MR. Increased variation in numbers of presacral vertebrae in suspensory mammals. Nat Ecol Evol 2019; 3:949-956. [DOI: 10.1038/s41559-019-0894-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 04/08/2019] [Indexed: 11/09/2022]
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14
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Pickering TR, Heaton JL, Clarke RJ, Stratford D. Hominin vertebrae and upper limb bone fossils from Sterkfontein Caves, South Africa (1998-2003 excavations). AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 168:459-480. [DOI: 10.1002/ajpa.23758] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 09/08/2018] [Accepted: 11/05/2018] [Indexed: 12/19/2022]
Affiliation(s)
- Travis Rayne Pickering
- Department of Anthropology; University of Wisconsin-Madison; Madison Wisconsin
- Evolutionary Studies Institute; University of the Witwatersand; Johannesburg South Africa
- Plio-Pleistocene Palaeontology Section, Department of Vertebrates; Ditsong National Museum of Natural History (Transvaal Museum); Pretoria South Africa
| | - Jason L. Heaton
- Evolutionary Studies Institute; University of the Witwatersand; Johannesburg South Africa
- Plio-Pleistocene Palaeontology Section, Department of Vertebrates; Ditsong National Museum of Natural History (Transvaal Museum); Pretoria South Africa
- Department of Biology; Birmingham-Southern College; Birmingham Alabama
| | - R. J. Clarke
- Evolutionary Studies Institute; University of the Witwatersand; Johannesburg South Africa
| | - Dominic Stratford
- School of Geography, Archaeology and Environmental Studies; University of the Witwatersrand; Johannesburg South Africa
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15
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Boyle EK, McNutt EJ, Sasaki T, Suwa G, Zipfel B, DeSilva JM. A quantification of calcaneal lateral plantar process position with implications for bipedal locomotion in Australopithecus. J Hum Evol 2018; 123:24-34. [PMID: 30075872 DOI: 10.1016/j.jhevol.2018.05.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 05/23/2018] [Accepted: 05/24/2018] [Indexed: 11/25/2022]
Abstract
The evolution of bipedalism in the hominin lineage has shaped the posterior human calcaneus into a large, robust structure considered to be adaptive for dissipating peak compressive forces and energy during heel-strike. A unique anatomy thought to contribute to the human calcaneus and its function is the lateral plantar process (LPP). While it has long been known that humans possess a plantarly positioned LPP and apes possess a more dorsally positioned homologous structure, the relative position of the LPP and intraspecific variation of this structure have never been quantified. Here, we present a method for quantifying relative LPP position and find that, while variable, humans have a significantly more plantar position of the LPP than that found in the apes. Among extinct hominins, while the position of the LPP in Australopithecus afarensis falls within the human distribution, the LPP is more dorsally positioned in Australopithecus sediba and barely within the modern human range of variation. Results from a resampling procedure suggest that these differences can reflect either individual variation of a foot structure/function largely shared among Australopithecus species, or functionally distinct morphologies that reflect locomotor diversity in Plio-Pleistocene hominins. An implication of the latter possibility is that calcaneal changes adaptive for heel-striking bipedalism may have evolved independently in two different hominin lineages.
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Affiliation(s)
- Eve K Boyle
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, 800 22nd St. NW, Suite 6000, Washington, DC 20052, USA.
| | - Ellison J McNutt
- Department of Anthropology, Dartmouth College, Hanover, NH 03755, USA; Ecology, Evolution, Ecosystems, and Society, Dartmouth College, Hanover, NH 03755, USA
| | - Tomohiko Sasaki
- The University Museum, The University of Tokyo, Tokyo, Japan
| | - Gen Suwa
- The University Museum, The University of Tokyo, Tokyo, Japan
| | - Bernhard Zipfel
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa; School of Geosciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Jeremy M DeSilva
- Department of Anthropology, Dartmouth College, Hanover, NH 03755, USA; Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
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16
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Meyer MR, Woodward C, Tims A, Bastir M. Neck function in early hominins and suspensory primates: Insights from the uncinate process. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 166:613-637. [PMID: 29492962 DOI: 10.1002/ajpa.23448] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 02/02/2018] [Accepted: 02/06/2018] [Indexed: 11/11/2022]
Abstract
OBJECTIVES Uncinate processes are protuberances on the cranial surface of subaxial cervical vertebrae that assist in stabilizing and guiding spinal motion. Shallow uncinate processes reduce cervical stability but confer an increased range of motion in clinical studies. Here we assess uncinate processes among extant primates and model cervical kinematics in early fossil hominins. MATERIALS AND METHODS We compare six fossil hominin vertebrae with 48 Homo sapiens and 99 nonhuman primates across 20 genera. We quantify uncinate morphology via geometric morphometric methods to understand how uncinate process shape relates to allometry, taxonomy, and mode of locomotion. RESULTS Across primates, allometry explains roughly 50% of shape variation, as small, narrow vertebrae feature the relatively tallest, most pronounced uncinate processes, whereas larger, wider vertebrae typically feature reduced uncinates. Taxonomy only weakly explains the residual variation, however, the association between Uncinate Shape and mode of locomotion is robust, as bipeds and suspensory primates occupy opposite extremes of the morphological continuum and are distinguished from arboreal generalists. Like humans, Australopithecus afarensis and Homo erectus exhibit shallow uncinate processes, whereas A. sediba resembles more arboreal taxa, but not fully suspensory primates. DISCUSSION Suspensory primates exhibit the most pronounced uncinates, likely to maintain visual field stabilization. East African hominins exhibit reduced uncinate processes compared with African apes and A. sediba, likely signaling different degrees of neck motility and modes of locomotion. Although soft tissues constrain neck flexibility beyond limits suggested by osteology alone, this study may assist in modeling cervical kinematics and positional behaviors in extinct taxa.
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Affiliation(s)
- Marc R Meyer
- Department of Anthropology, Chaffey College, Rancho Cucamonga, California 91737
| | - Charles Woodward
- Department of Anthropology, University of California, Berkeley, California 94720
| | - Amy Tims
- Department of Wildlife, Fish, & Conservation Biology, University of California, Davis, California 95616
| | - Markus Bastir
- Paleoanthropology Group, Museo Nacional de Ciencias Naturales (MNCN-CSIC), Madrid 28006, Spain
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17
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Arlegi M, Gómez‐Robles A, Gómez‐Olivencia A. Morphological integration in the gorilla, chimpanzee, and human neck. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 166:408-416. [DOI: 10.1002/ajpa.23441] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 01/31/2018] [Accepted: 02/01/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Mikel Arlegi
- Department of Estratigrafía y Paleontología, Facultad de Ciencia y TecnologíaEuskal Herriko Unibertsitatea (UPV/EHU), Barrio Sarriena s/nLeioa, 48940 Spain
- Université de Bordeaux, PACEA UMR 5199, Bâtiment B8, Allée Geoffroy Saint‐HilairePessac 33615 France
| | - Aida Gómez‐Robles
- Department of Genetics, Evolution, and EnvironmentUniversity College LondonLondon WC1E 6BT United Kingdom
- Department of Life SciencesNatural History MuseumLondon SW7 5BD United Kingdom
| | - Asier Gómez‐Olivencia
- Department of Estratigrafía y Paleontología, Facultad de Ciencia y TecnologíaEuskal Herriko Unibertsitatea (UPV/EHU), Barrio Sarriena s/nLeioa, 48940 Spain
- IKERBASQUE. Basque Foundation for Science Spain
- Centro UCM‐ISCIII de Investigación sobre Evolución y Comportamiento Humanos, Avda. Monforte de Lemos 5 (Pabellón 14)Madrid 28029 Spain
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18
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Brassey CA, O'Mahoney TG, Chamberlain AT, Sellers WI. A volumetric technique for fossil body mass estimation applied to Australopithecus afarensis. J Hum Evol 2018; 115:47-64. [DOI: 10.1016/j.jhevol.2017.07.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 07/26/2017] [Accepted: 07/26/2017] [Indexed: 12/27/2022]
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19
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de Ruiter DJ, Churchill S, Hawks J, Berger L. Late Australopiths and the Emergence of Homo. ANNUAL REVIEW OF ANTHROPOLOGY 2017. [DOI: 10.1146/annurev-anthro-102116-041734] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
New fossil discoveries and new analyses increasingly blur the lines between Australopithecus and Homo, changing scientific ideas about the transition between the two genera. The concept of the genus itself remains an unsettled issue, though recent fossil discoveries and theoretical advances, alongside developments in phylogenetic reconstruction and hypothesis testing, are helping us approach a resolution. A review of the latest discoveries and research reveals that (a) despite the recent recovery of key fossil specimens, the antiquity of the genus Homo remains uncertain; (b) although there exist several australopith candidate ancestors for the genus Homo, there is little consensus about which of these, if any, represents the actual ancestor; and (c) potential convergent evolution (homoplasy) in adaptively significant features in late australopiths and basal members of the Homo clade, combined with probable reticulate evolution, makes it currently impossible to identify the direct ancestor of Homo erectus.
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Affiliation(s)
- Darryl J. de Ruiter
- Department of Anthropology, Texas A&M University, College Station, Texas 77843
- Evolutionary Studies Institute and Centre for Excellence in PalaeoSciences, University of the Witwatersrand, Wits 2050, South Africa
| | - S.E. Churchill
- Evolutionary Studies Institute and Centre for Excellence in PalaeoSciences, University of the Witwatersrand, Wits 2050, South Africa
- Department of Evolutionary Anthropology, Duke University, Durham, North Carolina 27708
| | - J. Hawks
- Evolutionary Studies Institute and Centre for Excellence in PalaeoSciences, University of the Witwatersrand, Wits 2050, South Africa
- Department of Anthropology, University of Wisconsin, Madison, Wisconsin 53706
| | - L.R. Berger
- Evolutionary Studies Institute and Centre for Excellence in PalaeoSciences, University of the Witwatersrand, Wits 2050, South Africa
- School of Geosciences, University of the Witwatersrand, Wits 2050, South Africa
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20
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Thompson NE, Almécija S. The evolution of vertebral formulae in Hominoidea. J Hum Evol 2017; 110:18-36. [DOI: 10.1016/j.jhevol.2017.05.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 05/24/2017] [Accepted: 05/27/2017] [Indexed: 01/06/2023]
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21
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Thoracic vertebral count and thoracolumbar transition in Australopithecus afarensis. Proc Natl Acad Sci U S A 2017; 114:6000-6004. [PMID: 28533391 DOI: 10.1073/pnas.1702229114] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The evolution of the human pattern of axial segmentation has been the focus of considerable discussion in paleoanthropology. Although several complete lumbar vertebral columns are known for early hominins, to date, no complete cervical or thoracic series has been recovered. Several partial skeletons have revealed that the thoracolumbar transition in early hominins differed from that of most extant apes and humans. Australopithecus africanus, Australopithecus sediba, and Homo erectus all had zygapophyseal facets that shift from thoracic-like to lumbar-like at the penultimate rib-bearing level, rather than the ultimate rib-bearing level, as in most humans and extant African apes. What has not been clear is whether Australopithecus had 12 thoracic vertebrae as in most humans, or 13 as in most African apes, and where the position of the thoracolumbar transitional element was. The discovery, preparation, and synchrotron scanning of the Australopithecus afarensis partial skeleton DIK-1-1, from Dikika, Ethiopia, provides the only known complete hominin cervical and thoracic vertebral column before 60,000 years ago. DIK-1-1 is the only known Australopithecus skeleton to preserve all seven cervical vertebrae and provides evidence for 12 thoracic vertebrae with a transition in facet morphology at the 11th thoracic level. The location of this transition, one segment cranial to the ultimate rib-bearing vertebra, also occurs in all other early hominins and is higher than in most humans or extant apes. At 3.3 million years ago, the DIK-1-1 skeleton is the earliest example of this distinctive and unusual pattern of axial segmentation.
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22
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Hawks J, Elliott M, Schmid P, Churchill SE, Ruiter DJD, Roberts EM, Hilbert-Wolf H, Garvin HM, Williams SA, Delezene LK, Feuerriegel EM, Randolph-Quinney P, Kivell TL, Laird MF, Tawane G, DeSilva JM, Bailey SE, Brophy JK, Meyer MR, Skinner MM, Tocheri MW, VanSickle C, Walker CS, Campbell TL, Kuhn B, Kruger A, Tucker S, Gurtov A, Hlophe N, Hunter R, Morris H, Peixotto B, Ramalepa M, Rooyen DV, Tsikoane M, Boshoff P, Dirks PH, Berger LR. New fossil remains of Homo naledi from the Lesedi Chamber, South Africa. eLife 2017; 6. [PMID: 28483039 PMCID: PMC5423776 DOI: 10.7554/elife.24232] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 04/18/2017] [Indexed: 01/06/2023] Open
Abstract
The Rising Star cave system has produced abundant fossil hominin remains within the Dinaledi Chamber, representing a minimum of 15 individuals attributed to Homo naledi. Further exploration led to the discovery of hominin material, now comprising 131 hominin specimens, within a second chamber, the Lesedi Chamber. The Lesedi Chamber is far separated from the Dinaledi Chamber within the Rising Star cave system, and represents a second depositional context for hominin remains. In each of three collection areas within the Lesedi Chamber, diagnostic skeletal material allows a clear attribution to H. naledi. Both adult and immature material is present. The hominin remains represent at least three individuals based upon duplication of elements, but more individuals are likely present based upon the spatial context. The most significant specimen is the near-complete cranium of a large individual, designated LES1, with an endocranial volume of approximately 610 ml and associated postcranial remains. The Lesedi Chamber skeletal sample extends our knowledge of the morphology and variation of H. naledi, and evidence of H. naledi from both recovery localities shows a consistent pattern of differentiation from other hominin species.
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Affiliation(s)
- John Hawks
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, University of Wisconsin, Madison, United States
| | - Marina Elliott
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Peter Schmid
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Anthropological Institute and Museum, University of Zürich, Winterthurerstr, Zürich, Switzerland
| | - Steven E Churchill
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Evolutionary Anthropology, Duke University, Durham, United States
| | - Darryl J de Ruiter
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, Texas A&M University, College Station, United States
| | - Eric M Roberts
- Geosciences, College of Science and Engineering, James Cook University, Townsville, Australia
| | - Hannah Hilbert-Wolf
- Geosciences, College of Science and Engineering, James Cook University, Townsville, Australia
| | - Heather M Garvin
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology/Archaeology, Mercyhurst University, Erie, United States.,Department of Applied Forensic Sciences, Mercyhurst University, Erie, United States
| | - Scott A Williams
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Center for the Study of Human Origins, Department of Anthropology, New York University, New York, United States.,New York Consortium in Evolutionary Primatology, New York, United States
| | - Lucas K Delezene
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, University of Arkansas, Fayetteville, United States
| | - Elen M Feuerriegel
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, University of Washington, Seattle, United States
| | - Patrick Randolph-Quinney
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,School of Anatomical Sciences, University of the Witwatersrand Medical School, Johannesburg, South Africa.,School of Forensic and Applied Sciences, University of Central Lancashire, Preston, United Kingdom
| | - Tracy L Kivell
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,School of Anthropology and Conservation, University of Kent, Canterbury, United Kingdom.,Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Myra F Laird
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Organismal Biology and Anatomy, University of Chicago, Chicago, United States
| | - Gaokgatlhe Tawane
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Jeremy M DeSilva
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, Dartmouth College, Hanover, United States
| | - Shara E Bailey
- Center for the Study of Human Origins, Department of Anthropology, New York University, New York, United States.,New York Consortium in Evolutionary Primatology, New York, United States
| | - Juliet K Brophy
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Geography and Anthropology, Louisiana State University, Baton Rouge, United States
| | - Marc R Meyer
- Department of Anthropology, Chaffey College, Rancho Cucamonga, United States
| | - Matthew M Skinner
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,School of Anthropology and Conservation, University of Kent, Canterbury, United Kingdom.,Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Matthew W Tocheri
- Department of Anthropology, Lakehead University, Thunder Bay, Canada.,Human Origins Program, Department of Anthropology, National Museum of Natural History, Smithsonian Institution, Washington, United States
| | - Caroline VanSickle
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, University of Wisconsin, Madison, United States.,Department of Anthropology, Bryn Mawr College, Bryn Mawr, United States
| | - Christopher S Walker
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Evolutionary Anthropology, Duke University, Durham, United States.,Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, United States
| | - Timothy L Campbell
- Department of Anthropology, Texas A&M University, College Station, United States
| | - Brian Kuhn
- Department of Geology, University of Johannesburg, Johannesburg, South Africa
| | - Ashley Kruger
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,School of Geosciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Steven Tucker
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Alia Gurtov
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, University of Wisconsin, Madison, United States
| | - Nompumelelo Hlophe
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Rick Hunter
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Hannah Morris
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Forestry and Natural Resources, University of Georgia, Athens, United States
| | - Becca Peixotto
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa.,Department of Anthropology, American University, Washington, United States
| | - Maropeng Ramalepa
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Dirk van Rooyen
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Mathabela Tsikoane
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Pedro Boshoff
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
| | - Paul Hgm Dirks
- Geosciences, College of Science and Engineering, James Cook University, Townsville, Australia
| | - Lee R Berger
- Evolutionary Studies Institute, University of the Witwatersrand, Wits, South Africa
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23
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Berger LR, Hawks J, Dirks PHGM, Elliott M, Roberts EM. Homo naledi and Pleistocene hominin evolution in subequatorial Africa. eLife 2017; 6:e24234. [PMID: 28483041 PMCID: PMC5423770 DOI: 10.7554/elife.24234] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 04/19/2017] [Indexed: 01/22/2023] Open
Abstract
New discoveries and dating of fossil remains from the Rising Star cave system, Cradle of Humankind, South Africa, have strong implications for our understanding of Pleistocene human evolution in Africa. Direct dating of Homo naledi fossils from the Dinaledi Chamber (Berger et al., 2015) shows that they were deposited between about 236 ka and 335 ka (Dirks et al., 2017), placing H. naledi in the later Middle Pleistocene. Hawks and colleagues (Hawks et al., 2017) report the discovery of a second chamber within the Rising Star system (Dirks et al., 2015) that contains H. naledi remains. Previously, only large-brained modern humans or their close relatives had been demonstrated to exist at this late time in Africa, but the fossil evidence for any hominins in subequatorial Africa was very sparse. It is now evident that a diversity of hominin lineages existed in this region, with some divergent lineages contributing DNA to living humans and at least H. naledi representing a survivor from the earliest stages of diversification within Homo. The existence of a diverse array of hominins in subequatorial comports with our present knowledge of diversity across other savanna-adapted species, as well as with palaeoclimate and paleoenvironmental data. H. naledi casts the fossil and archaeological records into a new light, as we cannot exclude that this lineage was responsible for the production of Acheulean or Middle Stone Age tool industries.
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Affiliation(s)
- Lee R Berger
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
| | - John Hawks
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
- Department of Anthropology, University of Wisconsin, Madison, United States
| | - Paul HGM Dirks
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
- Department of Geosciences, James Cook University, Townsville, Australia
| | - Marina Elliott
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
| | - Eric M Roberts
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
- Department of Geosciences, James Cook University, Townsville, Australia
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Tardieu C, Hasegawa K, Haeusler M. How Did the Pelvis and Vertebral Column Become a Functional Unit during the Transition from Occasional to Permanent Bipedalism? Anat Rec (Hoboken) 2017; 300:912-931. [DOI: 10.1002/ar.23577] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 01/17/2017] [Accepted: 01/27/2017] [Indexed: 01/31/2023]
Affiliation(s)
- Christine Tardieu
- UMR 7179 “Mécanismes adaptatifs: des organismes aux communautés”, USM 301-Département E.G.B; Muséum National d'Histoire Naturelle; Paris France
| | | | - Martin Haeusler
- Institute of Evolutionary Medicine, University of Zürich; Zürich Switzerland
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Arlegi M, Gómez-Olivencia A, Albessard L, Martínez I, Balzeau A, Arsuaga JL, Been E. The role of allometry and posture in the evolution of the hominin subaxial cervical spine. J Hum Evol 2017; 104:80-99. [PMID: 28317557 DOI: 10.1016/j.jhevol.2017.01.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 01/02/2017] [Accepted: 01/04/2017] [Indexed: 12/01/2022]
Abstract
Cervical vertebrae not only protect the spinal cord but also are the insertion and origin points for muscles related to the movement of the head, upper limb, and trunk, among others, and are thus important elements in primate evolution. While previous work has been undertaken on the first two cervical vertebrae, there is a dearth of studies on the subaxial cervical spine in hominines. In this paper, we provide detailed morphological information on two important aspects of the subaxial cervical vertebrae (C3 - C7): mid-sagittal morphology and superior facet orientation. We studied large samples of African apes including modern humans and the most complete fossil hominin subaxial cervical vertebrae using both traditional and geometric morphometrics. There are significant differences between extant hominoids related to the relative length and orientation of the spinous process as well as to the orientation of the articular facets, which are related to size, locomotion, and neck posture. In fact, fossil hominins do not completely conform to any of the extant groups. Our assessment of mid-sagittal morphology and superior articular facet orientation shows that australopiths have more Homo-like upper subaxial cervical vertebrae coupled with more "primitive" lower cervical vertebrae. Based on these results, we hypothesize that those changes, maybe related to postural changes derived from bipedalism, did not affect the entire subaxial cervical spine at once. From a methodological point of view, the combination of traditional and geometric morphometric data provides a more integrative perspective of morphological change and evolution, which is certainly useful in human evolutionary studies.
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Affiliation(s)
- Mikel Arlegi
- Dept. Estratigrafía y Paleontología, Facultad de Ciencia y Tecnología, Euskal Herriko Unibertsitatea, UPV-EHU. Apdo. 644, 48080 Bilbao, Spain.
| | - Asier Gómez-Olivencia
- Dept. Estratigrafía y Paleontología, Facultad de Ciencia y Tecnología, Euskal Herriko Unibertsitatea, UPV-EHU. Apdo. 644, 48080 Bilbao, Spain; IKERBASQUE, Basque Foundation for Science, Spain; Équipe de Paléontologie Humaine, UMR 7194, CNRS, Département de Préhistoire, Muséum national d'Histoire naturelle, Musée de l'Homme, 17, Place du Trocadéro, 75016 Paris, France; Centro UCM-ISCIII de Investigación sobre Evolución y Comportamiento Humanos, Avda. Monforte de Lemos 5 (Pabellón 14), 28029 Madrid, Spain.
| | - Lou Albessard
- Équipe de Paléontologie Humaine, UMR 7194, CNRS, Département de Préhistoire, Muséum national d'Histoire naturelle, Musée de l'Homme, 17, Place du Trocadéro, 75016 Paris, France
| | - Ignacio Martínez
- Área de Antropología Física, Depto. de Ciencias de la Vida, Universidad de Alcalá, Alcalá de Henares 28871, Spain; Centro UCM-ISCIII de Investigación sobre Evolución y Comportamiento Humanos, Avda. Monforte de Lemos 5 (Pabellón 14), 28029 Madrid, Spain
| | - Antoine Balzeau
- Équipe de Paléontologie Humaine, UMR 7194, CNRS, Département de Préhistoire, Muséum national d'Histoire naturelle, Musée de l'Homme, 17, Place du Trocadéro, 75016 Paris, France; Department of African Zoology, Royal Museum for Central Africa, Tervuren, Belgium
| | - Juan Luis Arsuaga
- Dpto. de Paleontología, Fac. Ciencias Geológicas, Universidad Complutense de Madrid, Avda. Complutense s/n, Madrid 28040, Spain; Équipe de Paléontologie Humaine, UMR 7194, CNRS, Département de Préhistoire, Muséum national d'Histoire naturelle, Musée de l'Homme, 17, Place du Trocadéro, 75016 Paris, France
| | - Ella Been
- Physical Therapy Department, Faculty of Health Professions, Ono Academic College, Kiryat Ono 5545173, Israel; Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel Aviv University, 39040 Tel Aviv, Israel
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Gómez-Olivencia A, Arlegi M, Barash A, Stock JT, Been E. The Neandertal vertebral column 2: The lumbar spine. J Hum Evol 2017; 106:84-101. [PMID: 28434542 DOI: 10.1016/j.jhevol.2017.01.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 12/26/2016] [Accepted: 01/20/2017] [Indexed: 12/26/2022]
Abstract
Here we provide the most extensive metric and morphological analysis performed to date on the Neandertal lumbar spine. Neandertal lumbar vertebrae show differences from modern humans in both the vertebral body and in the neural arch, although not all Neandertal lumbar vertebrae differ from modern humans in the same way. Differences in the vertebral foramen are restricted to the lowermost lumbar vertebrae (L4 and L5), differences in the orientation of the upper articular facets appear in the uppermost lumbar vertebrae (probably in L1 and L2-L3), and differences in the horizontal angle of the transverse process appear in L2-L4. Neandertals, when compared to modern humans, show a smaller degree of lumbar lordosis. Based on a still limited fossil sample, early hominins (australopiths and Homo erectus) had a lumbar lordosis that was similar to but below the mean of modern humans. Here, we hypothesize that from this ancestral degree of lumbar lordosis, the Neandertal lineage decreased their lumbar lordosis and Homo sapiens slightly increased theirs. From a postural point of view, the lower degree of lordosis is related to a more vertical position of the sacrum, which is also positioned more ventrally with respect to the dorsal end of the pelvis. This results in a spino-pelvic alignment that, though different from modern humans, maintained an economic postural equilibrium. Some features, such as a lower degree of lumbar lordosis, were already present in the middle Pleistocene populations ancestral to Neandertals. However, these middle Pleistocene populations do not show the full suite of Neandertal lumbar morphologies, which probably means that the characteristic features of the Neandertal lumbar spine did not arise all at once.
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Affiliation(s)
- Asier Gómez-Olivencia
- Dept. Estratigrafía y Paleontología, Facultad de Ciencia y Tecnología, Euskal Herriko Unibertsitatea, UPV-EHU. Apdo. 644, 48080 Bilbao, Spain; IKERBASQUE, Basque Foundation for Science, Spain; Équipe de Paléontologie Humaine, UMR 7194, CNRS, Département de Préhistoire, Muséum national d'Histoire naturelle, Musée de l'Homme, 17, Place du Trocadéro, 75016 Paris, France; Centro UCM-ISCIII de Investigación sobre Evolución y Comportamiento Humanos, Avda. Monforte de Lemos 5 (Pabellón 14), 28029 Madrid, Spain.
| | - Mikel Arlegi
- Dept. Estratigrafía y Paleontología, Facultad de Ciencia y Tecnología, Euskal Herriko Unibertsitatea, UPV-EHU. Apdo. 644, 48080 Bilbao, Spain
| | - Alon Barash
- Faculty of Medicine in the Galilee, Bar Ilan University, Zefat 1311502, Israel
| | - Jay T Stock
- PAVE Research Group, Department of Archaeology and Anthropology, University of Cambridge, Pembroke Street, Cambridge CB2 3DZ, UK
| | - Ella Been
- Physical Therapy Department, Faculty of Health Professions, Ono Academic College, Kiryat Ono 5545173, Israel; Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel Aviv University, 39040 Tel Aviv, Israel
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27
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The cervical spine of Australopithecus sediba. J Hum Evol 2017; 104:32-49. [DOI: 10.1016/j.jhevol.2017.01.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 12/31/2016] [Accepted: 01/04/2017] [Indexed: 11/22/2022]
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Williams SA, García-Martínez D, Bastir M, Meyer MR, Nalla S, Hawks J, Schmid P, Churchill SE, Berger LR. The vertebrae and ribs of Homo naledi. J Hum Evol 2017; 104:136-154. [DOI: 10.1016/j.jhevol.2016.11.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 11/16/2016] [Accepted: 11/17/2016] [Indexed: 10/20/2022]
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Mandibular ramus shape of Australopithecus sediba suggests a single variable species. J Hum Evol 2016; 100:54-64. [DOI: 10.1016/j.jhevol.2016.09.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 08/30/2016] [Accepted: 09/01/2016] [Indexed: 11/19/2022]
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Ohlsson M, Nieto JH, Christe KL, Villablanca JP, Havton LA. Radiographic and Magnetic Resonance Imaging Identification of Thoracolumbar Spine Variants with Implications for the Positioning of the Conus Medullaris in Rhesus Macaques. Anat Rec (Hoboken) 2016; 300:300-308. [PMID: 27731939 DOI: 10.1002/ar.23495] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Accepted: 12/23/2015] [Indexed: 02/03/2023]
Abstract
The anatomy of the vertebral column in mammals may differ between species and between subjects of the same species, especially with regards to the composition of the thoracolumbar spine. We investigated, using several noninvasive imaging techniques, the thoracolumbar spine of a total of 44 adult rhesus macaques of both genders. Radiographic examination of the vertebral column showed a predominant spine phenotype with 12 rib-bearing thoracic vertebrae and 7 lumbar vertebrae without ribs in 82% of subjects, whereas a subset of subjects demonstrated 13 rib-bearing thoracic vertebrae and 6 lumbar vertebrae without ribs. Computer tomography studies of the thoraco-lumbar spine in two cases with a pair of supernumerary ribs showed facet joints between the most caudal pair of ribs and the associated vertebra, supporting a thoracic phenotype. Magnetic resonance imaging (MRI) studies were used to determine the relationship between the lumbosacral spinal cord and the vertebral column. The length of the conus medullaris portion of the spinal cord was 1.5 ± 0.3 vertebral units, and its rostral and caudal positions in the spinal canal were at 2.0 ± 0.3 and 3.6 ± 0.4 vertebral units below the thoracolumbar junction, respectively (n = 44). The presence of a set of supernumerary ribs did not affect the length or craniocaudal position of the conus medullaris, and subjects with13 rib-bearing vertebrae may from a functional or spine surgical perspective be considered as exhibiting12 thoracic vertebrae and an L1 vertebra with ribs. Anat Rec, 300:300-308, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Marcus Ohlsson
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California.,Department of Clinical Neuroscience, Divisions of Neurosurgery and Neuroradiology, Karolinska Institute, Stockholm, Sweden
| | - Jaime H Nieto
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Kari L Christe
- California National Primate Research Center, UC Davis, Davis, California
| | - J Pablo Villablanca
- Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Leif A Havton
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California
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31
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Randolph-Quinney PS, Williams SA, Steyn M, Meyer MR, Smilg JS, Churchill SE, Odes EJ, Augustine T, Tafforeau P, Berger LR. Osteogenic tumour in Australopithecus sediba: Earliest hominin evidence for neoplastic disease. S AFR J SCI 2016. [DOI: 10.17159/sajs.2016/20150470] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Abstract We describe the earliest evidence for neoplastic disease in the hominin lineage. This is reported from the type specimen of the extinct hominin Australopithecus sediba from Malapa, South Africa, dated to 1.98 million years ago. The affected individual was male and developmentally equivalent to a human child of 12 to 13 years of age. A penetrating lytic lesion affected the sixth thoracic vertebra. The lesion was macroscopically evaluated and internally imaged through phase-contrast X-ray synchrotron microtomography. A comprehensive differential diagnosis was undertaken based on gross- and micro-morphology of the lesion, leading to a probable diagnosis of osteoid osteoma. These neoplasms are solitary, benign, osteoid and bone-forming tumours, formed from well-vascularised connective tissue within which there is active production of osteoid and woven bone. Tumours of any kind are rare in archaeological populations, and are all but unknown in the hominin record, highlighting the importance of this discovery. The presence of this disease at Malapa predates the earliest evidence of malignant neoplasia in the hominin fossil record by perhaps 200 000 years.
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Irish JD, Hemphill BE, de Ruiter DJ, Berger LR. The apportionment of tooth size and its implications in
Australopithecus sediba
versus other Plio‐pleistocene and recent African hominins. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2016; 161:398-413. [DOI: 10.1002/ajpa.23039] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2015] [Revised: 06/08/2016] [Accepted: 06/09/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Joel D. Irish
- Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences and PsychologyLiverpool John Moores UniversityLiverpoolL3 3AF UK
- Evolutionary Studies Institute and Centre for Excellence in PaleoSciencesUniversity of the WitwatersrandPrivate Bag 3, WITS 2050Johannesburg South Africa
| | | | - Darryl J. de Ruiter
- Department of AnthropologyTexas A&M UniversityCollege Station TX77843
- Evolutionary Studies Institute and Centre for Excellence in PaleoSciencesUniversity of the WitwatersrandPrivate Bag 3, WITS 2050Johannesburg South Africa
| | - Lee R. Berger
- Evolutionary Studies Institute and Centre for Excellence in PaleoSciencesUniversity of the WitwatersrandPrivate Bag 3, WITS 2050Johannesburg South Africa
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Williams SA, Russo GA. The fifth element (of Lucy's sacrum): Reply to Machnicki, Lovejoy, and Reno. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2016; 161:374-8. [DOI: 10.1002/ajpa.23035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Machnicki AL, Lovejoy CO, Reno PL. Developmental identity versus typology: Lucy has only four sacral segments. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2016; 160:729-39. [DOI: 10.1002/ajpa.22997] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 02/25/2016] [Accepted: 03/31/2016] [Indexed: 12/28/2022]
Affiliation(s)
| | - C. Owen Lovejoy
- Department of Anthropology and School of Biomedical SciencesKent State UniversityKent OH
| | - Philip L. Reno
- Department of AnthropologyPennsylvania State UniversityUniversity Park PA
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Williams SA, Middleton ER, Villamil CI, Shattuck MR. Vertebral numbers and human evolution. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2016; 159:S19-36. [DOI: 10.1002/ajpa.22901] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Scott A. Williams
- Department of Anthropology; Center for the Study of Human Origins, New York University; New York NY 10003
- New York Consortium in Evolutionary Primatology; New York NY
| | - Emily R. Middleton
- Department of Anthropology; Center for the Study of Human Origins, New York University; New York NY 10003
- New York Consortium in Evolutionary Primatology; New York NY
| | - Catalina I. Villamil
- Department of Anthropology; Center for the Study of Human Origins, New York University; New York NY 10003
- New York Consortium in Evolutionary Primatology; New York NY
| | - Milena R. Shattuck
- Department of Anthropology; Center for the Study of Human Origins, New York University; New York NY 10003
- New York Consortium in Evolutionary Primatology; New York NY
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36
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Meyer MR, Haeusler M. Spinal cord evolution in early Homo. J Hum Evol 2015; 88:43-53. [DOI: 10.1016/j.jhevol.2015.09.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Revised: 08/31/2015] [Accepted: 09/01/2015] [Indexed: 10/22/2022]
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Gilbert CC, Steininger CM, Kibii JM, Berger LR. Papio Cranium from the Hominin-Bearing Site of Malapa: Implications for the Evolution of Modern Baboon Cranial Morphology and South African Plio-Pleistocene Biochronology. PLoS One 2015; 10:e0133361. [PMID: 26287673 PMCID: PMC4545885 DOI: 10.1371/journal.pone.0133361] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Accepted: 06/25/2015] [Indexed: 11/24/2022] Open
Abstract
A new partial cranium (UW 88-886) of the Plio-Pleistocene baboon Papio angusticeps from Malapa is identified, described and discussed. UW 88-886 represents the only non-hominin primate yet recovered from Malapa and is important both in the context of baboon evolution as well as South African hominin site biochronology. The new specimen may represent the first appearance of modern baboon anatomy and coincides almost perfectly with molecular divergence date estimates for the origin of the modern P. hamadryas radiation. The fact that the Malapa specimen is dated between ~2.026–2.36 million years ago (Ma) also has implications for the biochronology of other South African Plio-Pleistocene sites where P. angusticeps is found.
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Affiliation(s)
- Christopher C. Gilbert
- Department of Anthropology, Hunter College of the City University of New York, 695 Park Avenue, New York, NY, 10065, United States of America
- PhD Programs in Anthropology and Biology, Graduate Center of the City University of New York, 365 Fifth Avenue, New York, NY, 10016, United States of America
- New York Consortium in Evolutionary Primatology, New York, NY, United States of America
- * E-mail:
| | - Christine M. Steininger
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, Johannesburg, Republic of South Africa
| | - Job M. Kibii
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, Johannesburg, Republic of South Africa
| | - Lee R. Berger
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, Johannesburg, Republic of South Africa
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Meyer MR, Williams SA, Smith MP, Sawyer GJ. Lucy's back: Reassessment of fossils associated with the A.L. 288-1 vertebral column. J Hum Evol 2015; 85:174-80. [DOI: 10.1016/j.jhevol.2015.05.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 05/10/2015] [Accepted: 05/13/2015] [Indexed: 10/23/2022]
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Reno PL. Genetic and developmental basis for parallel evolution and its significance for hominoid evolution. Evol Anthropol 2015; 23:188-200. [PMID: 25347977 DOI: 10.1002/evan.21417] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Greater understanding of ape comparative anatomy and evolutionary history has brought a general appreciation that the hominoid radiation is characterized by substantial homoplasy.(1-4) However, little consensus has been reached regarding which features result from repeated evolution. This has important implications for reconstructing ancestral states throughout hominoid evolution, including the nature of the Pan-Homo last common ancestor (LCA). Advances from evolutionary developmental biology (evo-devo) have expanded the diversity of model organisms available for uncovering the morphogenetic mechanisms underlying instances of repeated phenotypic change. Of particular relevance to hominoids are data from adaptive radiations of birds, fish, and even flies demonstrating that parallel phenotypic changes often use similar genetic and developmental mechanisms. The frequent reuse of a limited set of genes and pathways underlying phenotypic homoplasy suggests that the conserved nature of the genetic and developmental architecture of animals can influence evolutionary outcomes. Such biases are particularly likely to be shared by closely related taxa that reside in similar ecological niches and face common selective pressures. Consideration of these developmental and ecological factors provides a strong theoretical justification for the substantial homoplasy observed in the evolution of complex characters and the remarkable parallel similarities that can occur in closely related taxa. Thus, as in other branches of the hominoid radiation, repeated phenotypic evolution within African apes is also a distinct possibility. If so, the availability of complete genomes for each of the hominoid genera makes them another model to explore the genetic basis of repeated evolution.
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Affiliation(s)
- Philip L Reno
- Department of Anthropology, The Pennsylvania State University, University Park, PA, 16802
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40
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Williams SA, Russo GA. Evolution of the hominoid vertebral column: The long and the short of it. Evol Anthropol 2015; 24:15-32. [DOI: 10.1002/evan.21437] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Russo GA, Williams SA. “Lucy” (A.L. 288-1) had five sacral vertebrae. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2014; 156:295-303. [DOI: 10.1002/ajpa.22642] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 09/10/2014] [Accepted: 10/08/2014] [Indexed: 12/13/2022]
Affiliation(s)
- Gabrielle A. Russo
- Department of Anthropology and IDPAS; Stony Brook University; Stony Brook NY 11794
| | - Scott A. Williams
- Center for the Study of Human Origins, Department of Anthropology; New York University; New York NY 10003
- New York Consortium in Evolutionary Primatology; New York NY 10024
- Evolutionary Studies Institute and Centre for Excellence in PalaeoSciences, University of the Witwatersrand; Wits 2050 South Africa
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42
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MacKinnon KC. Contemporary Biological Anthropology in 2013: Integrative, Connected, and Relevant. AMERICAN ANTHROPOLOGIST 2014. [DOI: 10.1111/aman.12102] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Been E, Gómez-Olivencia A, Kramer PA. Brief communication: Lumbar lordosis in extinct hominins: implications of the pelvic incidence. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2014; 154:307-14. [PMID: 24615397 DOI: 10.1002/ajpa.22507] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 02/21/2014] [Accepted: 02/26/2014] [Indexed: 12/29/2022]
Abstract
Recently, interest has peaked regarding the posture of extinct hominins. Here, we present a new method of reconstructing lordosis angles of extinct hominin specimens based on pelvic morphology, more specifically the orientation of the sacrum in relation to the acetabulum (pelvic incidence). Two regression models based on the correlation between pelvic incidence and lordosis angle in living hominoids have been developed. The mean values of the calculated lordosis angles based on these models are 36°-45° for australopithecines, 45°-47° for Homo erectus, 27°-34° for the Neandertals and the Sima de los Huesos hominins, and 49°-51° for fossil H. sapiens. The newly calculated lordosis values are consistent with previously published values of extinct hominins (Been et al.: Am J Phys Anthropol 147 (2012) 64-77). If the mean values of the present nonhuman hominoids are representative of the pelvic and lumbar morphology of the last common ancestor between humans and nonhuman hominoids, then both pelvic incidence and lordosis angle dramatically increased during hominin evolution from 27° ± 5 to 22° ± 3 (respectively) in nonhuman hominoids to 54° ± 10 and 51° ± 11 in modern humans. This change to a more human-like configuration appeared early in the hominin evolution as the pelvis and spines of both australopithecines and H. erectus show a higher pelvic incidence and lordosis angle than nonhuman hominoids. The Sima de los Huesos hominins and Neandertals show a derived configuration with a low pelvic incidence and lordosis angle.
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Affiliation(s)
- Ella Been
- Department of Anatomy and Anthropology Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel; Department of Physical Therapy Faculty of Health Professions, Ono Academic College, Kiryat Ono, 55000, Israel
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Mohammadparast S, Bayat H, Biglarian A, Ohadi M. Exceptional expansion and conservation of a CT-repeat complex in the core promoter of PAXBP1 in primates. Am J Primatol 2014; 76:747-56. [PMID: 24573656 DOI: 10.1002/ajp.22266] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 12/28/2013] [Accepted: 01/28/2014] [Indexed: 11/11/2022]
Abstract
Adaptive evolution may be linked with the genomic distribution and function of short tandem repeats (STRs). Proximity of the core promoter STRs to the +1 transcription start site (TSS), and their mutable nature are characteristics that highlight those STRs as a novel source of interspecies variation. The PAXBP1 gene (alternatively known as GCFC1) core promoter contains the longest STR identified in a Homo sapiens gene core promoter. Indeed, this core promoter is a stretch of four consecutive CT-STRs. In the current study, we used the Ensembl, NCBI, and UCSC databases to analyze the evolutionary trend and functional implication of this CT-STR complex in six major lineages across vertebrates, including primates, non-primate mammals, birds, reptiles, amphibians, and fish. We observed exceptional expansion (≥4-repeats) and conservation of this CT-STR complex across primates, except prosimians, Microcebus murinus and Otolemur garnettii (Fisher exact P<4.1×10(-7)). H. sapiens has the most complex STR formula, and longest repeats. Macaca mulatta and Callithrix jacchus monkeys have the simplest STR formulas, and shortest repeat numbers. CT≥4-repeats were not detected in non-primate lineages. Different length alleles across the PAXBP1 core promoter CT-STRs significantly altered gene expression in vitro (P<0.001, t-test). PAXBP1 has a crucial role in craniofacial development, myogenesis, and spine morphogenesis, properties that have been diverged between primates and non-primates. To our knowledge, this is the first instance of expansion and conservation of a STR complex co-occurring specifically with the primate lineage.
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Affiliation(s)
- Saeid Mohammadparast
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
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Schiess R, Boeni T, Rühli F, Haeusler M. Revisiting scoliosis in the KNM-WT 15000 Homo erectus skeleton. J Hum Evol 2014; 67:48-59. [PMID: 24491377 DOI: 10.1016/j.jhevol.2013.12.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Revised: 10/25/2013] [Accepted: 12/10/2013] [Indexed: 12/12/2022]
Abstract
Owing to its completeness, the 1.5 million year old Nariokotome boy skeleton KNM-WT 15000 is central for understanding the skeletal biology of Homo erectus. Nevertheless, since the reported asymmetries and distortions of Nariokotome boy's axial skeleton suggest adolescent idiopathic scoliosis, possibly associated with congenital skeletal dysplasia, it is questionable whether it still can be used as a reference for H. erectus. Recently, however, the presence of skeletal dysplasia has been refuted. Here, we present a morphological and morphometric reanalysis of the assertion of idiopathic scoliosis. We demonstrate that unarticulated vertebral columns of non-scoliotic and scoliotic individuals can be distinguished based on the lateral deviation of the spinous process, lateral and sagittal wedging, vertebral body torsion, pedicle thickness asymmetry, and asymmetry of superior and inferior articular facet areas. A principal component analysis of the overall asymmetry of all seven vertebral shape variables groups KNM-WT 15000 within non-scoliotic modern humans. There is, however, an anomaly of vertebrae T1-T2 that is compatible with a short left convex curve at the uppermost thoracic region, possibly due to injury or local growth dysbalance. Asymmetries of the facet joints L3-L5 suggest a local right convex curve in the lower lumbar region that probably resulted from juvenile traumatic disc herniation. This pattern is incompatible with adolescent idiopathic scoliosis or other types of scoliosis, including congenital, neuromuscular or syndromic scoliosis. It is, however, consistent with a recent reanalysis of the rib cage that did not reveal any asymmetry. Except for these possibly trauma-related anomalies, the Nariokotome boy fossil therefore seems to belong to a normal H. erectus youth without evidence for adolescent idiopathic scoliosis or other severe pathologies of the axial skeleton.
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Affiliation(s)
- Regula Schiess
- Anthropological Institute and Museum, University of Zuerich, Winterthurerstrasse 190, 8057 Zuerich, Switzerland
| | - Thomas Boeni
- Orthopaedische Universitaetsklinik Balgrist, Forchstrasse 340, 8008 Zuerich, Switzerland; Centre for Evolutionary Medicine, Institute of Anatomy, University of Zuerich, Winterthurerstrasse 190, 8057 Zuerich, Switzerland
| | - Frank Rühli
- Centre for Evolutionary Medicine, Institute of Anatomy, University of Zuerich, Winterthurerstrasse 190, 8057 Zuerich, Switzerland
| | - Martin Haeusler
- Anthropological Institute and Museum, University of Zuerich, Winterthurerstrasse 190, 8057 Zuerich, Switzerland; Centre for Evolutionary Medicine, Institute of Anatomy, University of Zuerich, Winterthurerstrasse 190, 8057 Zuerich, Switzerland.
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Tardieu C, Bonneau N, Hecquet J, Boulay C, Marty C, Legaye J, Duval-Beaupère G. How is sagittal balance acquired during bipedal gait acquisition? Comparison of neonatal and adult pelves in three dimensions. Evolutionary implications. J Hum Evol 2013; 65:209-22. [PMID: 23838060 DOI: 10.1016/j.jhevol.2013.06.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 05/21/2013] [Accepted: 06/03/2013] [Indexed: 12/13/2022]
Abstract
We compare adult and intact neonatal pelves, using a pelvic sagittal variable, the angle of sacral incidence, which presents significant correlations with vertebral curvature in adults and plays an important role in sagittal balance of the trunk on the lower limbs. Since the lumbar curvature develops in the child in association with gait acquisition, we expect a change in this angle during growth which could contribute to the acquisition of sagittal balance. To understand the mechanisms underlying the sagittal balance in the evolution of human bipedalism, we also measure the angle of incidence of hominid fossils. Fourty-seven landmarks were digitized on 50 adult and 19 intact neonatal pelves. We used a three-dimensional model of the pelvis (DE-VISU program) which calculates the angle of sacral incidence and related functional variables. Cross-sectional data from newborns and adults show that the angle of sacral incidence increases and becomes negatively correlated with the sacro-acetabular distance. During ontogeny the sacrum becomes curved, tends to sink down between the iliac blades as a wedge and moves backward in the sagittal plane relative to the acetabula, thus contributing to the backwards displacement of the center of gravity of the trunk. A chain of correlations links the degree of the sacral slope and of the angle of incidence, which is tightly linked with the lumbar lordosis. We sketch a model showing the coordinated changes occurring in the pelvis and vertebral column during the acquisition of bipedalism in infancy. In the australopithecine pelves, Sts 14 and AL 288-1, and in the Homo erectus Gona pelvis the angle of sacral incidence reaches the mean values of humans. Discussing the incomplete pelves of Ardipithecus ramidus, Australopithecus sediba and the Nariokotome Boy, we suggest how the functional linkage between pelvis and spine, observed in humans, could have emerged during hominid evolution.
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Affiliation(s)
- Christine Tardieu
- U.M.R. 7179 CNRS, Mécanismes adaptatifs: des organismes aux communautés, Pavillon d'Anatomie Comparée, M.N.H.N., 55 rue Buffon, 75 005 Paris, France.
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48
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Irish JD, Guatelli-Steinberg D, Legge SS, de Ruiter DJ, Berger LR. Dental Morphology and the Phylogenetic “Place” of
Australopithecus sediba. Science 2013; 340:1233062. [DOI: 10.1126/science.1233062] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Joel D. Irish
- Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool L3 3AF, UK
| | - Debbie Guatelli-Steinberg
- Department of Anthropology, and Department of Evolution, Ecology, and Organismal Biology, Ohio State University, Columbus, OH 43210, USA
| | - Scott S. Legge
- Department of Anthropology, Macalester College, St. Paul, MN 55105, USA
| | - Darryl J. de Ruiter
- Department of Anthropology, Texas A&M University, College Station, TX 77843, USA
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
| | - Lee R. Berger
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
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de Ruiter DJ, DeWitt TJ, Carlson KB, Brophy JK, Schroeder L, Ackermann RR, Churchill SE, Berger LR. Mandibular Remains Support Taxonomic Validity of
Australopithecus sediba. Science 2013; 340:1232997. [DOI: 10.1126/science.1232997] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Darryl J. de Ruiter
- Department of Anthropology, Texas A&M University, College Station, TX 77843, USA
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
| | - Thomas J. DeWitt
- Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX 77843, USA
| | - Keely B. Carlson
- Department of Anthropology, Texas A&M University, College Station, TX 77843, USA
| | - Juliet K. Brophy
- Department of Anthropology, Texas A&M University, College Station, TX 77843, USA
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
- Department of Anthropology, Loyola University, Chicago, IL 60660, USA
| | - Lauren Schroeder
- Department of Archaeology, University of Cape Town, Rondebosch 7701, South Africa
| | - Rebecca R. Ackermann
- Department of Archaeology, University of Cape Town, Rondebosch 7701, South Africa
| | - Steven E. Churchill
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
- Department of Evolutionary Anthropology, Box 90383, Duke University, Durham, NC 27708, USA
| | - Lee R. Berger
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
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50
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Schmid P, Churchill SE, Nalla S, Weissen E, Carlson KJ, de Ruiter DJ, Berger LR. Mosaic Morphology in the Thorax of
Australopithecus sediba. Science 2013; 340:1234598. [DOI: 10.1126/science.1234598] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Peter Schmid
- Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
| | - Steven E. Churchill
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
- Department of Evolutionary Anthropology, Box 90383, Duke University, Durham, NC 27708, USA
| | - Shahed Nalla
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
- Department of Human Anatomy and Physiology, Faculty of Health Sciences, University of Johannesburg, Johannesburg, South Africa
| | - Eveline Weissen
- Anthropological Institute and Museum, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland
| | - Kristian J. Carlson
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
- Department of Anthropology, Indiana University, Bloomington, IN 47405, USA
| | - Darryl J. de Ruiter
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
- Department of Anthropology, Texas A&M University, College Station, TX 77843, USA
| | - Lee R. Berger
- Evolutionary Studies Institute, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa
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