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Abstract
Here, we review the modern interface of three-dimensional (3D) empirical (e.g. motion capture) and theoretical (e.g. modelling and simulation) approaches to the study of terrestrial locomotion using appendages in tetrapod vertebrates. These tools span a spectrum from more empirical approaches such as XROMM, to potentially more intermediate approaches such as finite element analysis, to more theoretical approaches such as dynamic musculoskeletal simulations or conceptual models. These methods have much in common beyond the importance of 3D digital technologies, and are powerfully synergistic when integrated, opening a wide range of hypotheses that can be tested. We discuss the pitfalls and challenges of these 3D methods, leading to consideration of the problems and potential in their current and future usage. The tools (hardware and software) and approaches (e.g. methods for using hardware and software) in the 3D analysis of tetrapod locomotion have matured to the point where now we can use this integration to answer questions we could never have tackled 20 years ago, and apply insights gleaned from them to other fields.
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Affiliation(s)
- Oliver E. Demuth
- Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, UK
| | - Eva Herbst
- Palaeontological Institute and Museum, University of Zurich, 8006 Zürich, Switzerland
| | - Delyle T. Polet
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, North Mymms, AL9 7TA, UK
| | - Ashleigh L. A. Wiseman
- McDonald Institute for Archaeological Research, University of Cambridge, Cambridge, CB2 3ER, UK
| | - John R. Hutchinson
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, North Mymms, AL9 7TA, UK
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Lowi-Merri TM, Demuth OE, Benito J, Field DJ, Benson RBJ, Claramunt S, Evans DC. Reconstructing locomotor ecology of extinct avialans: a case study of Ichthyornis comparing sternum morphology and skeletal proportions. Proc Biol Sci 2023; 290:20222020. [PMID: 36883281 PMCID: PMC9993061 DOI: 10.1098/rspb.2022.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 02/08/2023] [Indexed: 03/09/2023] Open
Abstract
Avian skeletal morphology is associated with locomotor function, including flight style, swimming and terrestrial locomotion, and permits informed inferences on locomotion in extinct taxa. The fossil taxon Ichthyornis (Avialae: Ornithurae) has long been regarded as highly aerial, with flight similar to terns or gulls (Laridae), and skeletal features resembling foot-propelled diving adaptations. However, rigorous testing of locomotor hypotheses has yet to be performed on Ichthyornis, despite its notable phylogenetic position as one of the most crownward stem birds. We analysed separate datasets of three-dimensional sternal shape (geometric morphometrics) and skeletal proportions (linear measurements across the skeleton), to examine how well these data types predict locomotor traits in Neornithes. We then used this information to infer locomotor capabilities of Ichthyornis. We find strong support for both soaring and foot-propelled swimming capabilities in Ichthyornis. Further, sternal shape and skeletal proportions provide complementary information on avian locomotion: skeletal proportions allow better predictions of the capacity for flight, whereas sternal shape predicts variation in more specific locomotor abilities such as soaring, foot-propelled swimming and escape burst flight. These results have important implications for future studies of extinct avialan ecology and underscore the importance of closely considering sternum morphology in investigations of fossil bird locomotion.
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Affiliation(s)
- Talia M. Lowi-Merri
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, Canada M5S 3B2
- Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario, Canada M5S 2C6
| | - Oliver E. Demuth
- Department of Earth Sciences, University of Cambridge, Cambridge, UK
- Structure and Motion Laboratory, Royal Veterinary College, Hatfield, UK
| | - Juan Benito
- Department of Earth Sciences, University of Cambridge, Cambridge, UK
- Department of Biology and Biochemistry, Milner Centre for Evolution, University of Bath, Bath, UK
| | - Daniel J. Field
- Department of Earth Sciences, University of Cambridge, Cambridge, UK
- Museum of Zoology, University of Cambridge, Cambridge, UK
| | - Roger B. J. Benson
- Division of Paleontology, American Museum of Natural History, 200 Central Park West, New York, NY 12004, USA
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN, UK
| | - Santiago Claramunt
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, Canada M5S 3B2
- Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario, Canada M5S 2C6
| | - David C. Evans
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, Canada M5S 3B2
- Department of Natural History, Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario, Canada M5S 2C6
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Demuth OE, Wiseman ALA, Hutchinson JR. Quantitative biomechanical assessment of locomotor capabilities of the stem archosaur Euparkeria capensis. R Soc Open Sci 2023; 10:221195. [PMID: 36704253 PMCID: PMC9874271 DOI: 10.1098/rsos.221195] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 01/10/2023] [Indexed: 06/18/2023]
Abstract
Birds and crocodylians are the only remaining members of Archosauria (ruling reptiles) and they exhibit major differences in posture and gait, which are polar opposites in terms of locomotor strategies. Their broader lineages (Avemetatarsalia and Pseudosuchia) evolved a multitude of locomotor modes in the Triassic and Jurassic periods, including several occurrences of bipedalism. The exact timings and frequencies of bipedal origins within archosaurs, and thus their ancestral capabilities, are contentious. It is often suggested that archosaurs ancestrally exhibited some form of bipedalism. Euparkeria capensis is a central taxon for the investigation of locomotion in archosaurs due to its phylogenetic position and intermediate skeletal morphology, and is argued to be representative of facultative bipedalism in this group. However, no studies to date have biomechanically tested if bipedality was feasible in Eupakeria. Here, we use musculoskeletal models and static simulations in its hindlimb to test the influences of body posture and muscle parameter estimation methods on locomotor potential. Our analyses show that the resulting negative pitching moments around the centre of mass were prohibitive to sustainable bipedality. We conclude that it is unlikely that Euparkeria was facultatively bipedal, and was probably quadrupedal, rendering the inference of ancestral bipedal abilities in Archosauria unlikely.
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Affiliation(s)
- Oliver E. Demuth
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, The Royal Veterinary College, Hatfield, UK
- Department of Earth Sciences, University of Cambridge, Cambridge, UK
| | - Ashleigh L. A. Wiseman
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, The Royal Veterinary College, Hatfield, UK
- McDonald Institute for Archaeological Research, University of Cambridge, Cambridge, UK
| | - John R. Hutchinson
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, The Royal Veterinary College, Hatfield, UK
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Wiseman ALA, Demuth OE, Pomeroy E, De Groote I. Reconstructing Articular Cartilage in the Australopithecus afarensis Hip Joint and the Need for Modeling Six Degrees of Freedom. Integr Org Biol 2022; 4:obac031. [PMID: 36060864 PMCID: PMC9428927 DOI: 10.1093/iob/obac031] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 07/08/2022] [Accepted: 07/26/2022] [Indexed: 11/13/2022] Open
Abstract
Synopsis
The postcranial skeleton of Australopithecus afarensis (AL 288–1) exhibits clear adaptations for bipedality, although there is some debate as to the efficiency and frequency of such upright movement. Some researchers argue that AL 288–1 walked with an erect limb like modern humans do, whilst others advocate for a “bent-hip bent-knee” (BHBK) gait, although in recent years the general consensus favors erect bipedalism. To date, no quantitative method has addressed the articulation of the AL 288–1 hip joint, nor its range of motion (ROM) with consideration for joint spacing, used as a proxy for the thickness of the articular cartilage present within the joint spacing which can affect how a joint moves. Here, we employed ROM mapping methods to estimate the joint spacing of AL 288–1’s hip joint in comparison to a modern human and chimpanzee. Nine simulations assessed different joint spacing and tested the range of joint congruency (i.e., ranging from a closely packed socket to loosely packed). We further evaluated the sphericity of the femoral head and whether three rotational degrees of freedom (DOFs) sufficiently captures the full ROM or if translational DOFs must be included. With both setups, we found that the AL 288–1 hip was unlikely to be highly congruent (as it is in modern humans) because this would severely restrict hip rotational movement and would severely limit the capability for both bipedality and even arboreal locomotion. Rather, the hip was more cartilaginous than it is in the modern humans, permitting the hip to rotate into positions necessitated by both terrestrial and arboreal movements. Rotational-only simulations found that AL 288–1 was unable to extend the hip like modern humans, forcing the specimen to employ a BHBK style of walking, thus contradicting 40+ years of previous research into the locomotory capabilities of AL 288–1. Therefore, we advocate that differences in the sphericity of the AL 288–1 femoral head with that of a modern human necessitates all six DOFs to be included in which AL 288–1 could osteologically extend the hip to facilitate a human-like gait.
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Affiliation(s)
- Ashleigh L A Wiseman
- McDonald Institute for Archaeological Research, University of Cambridge , Cambridge CB2 1TN
- Research Centre in Evolutionary Anthropology and Paleoecology, Liverpool John Moores University , Liverpool, Merseyside L3 5UX
| | - Oliver E Demuth
- Department of Earth Sciences, University of Cambridge , Cambridge CB2 1TN
- Structure and Motion Laboratory , Royal Veterinary College, London NW1 0TU
| | - Emma Pomeroy
- Department of Archaeology, University of Cambridge , Cambridge CB2 1TN
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Cuff AR, Demuth OE, Michel K, Otero A, Pintore R, Polet DT, Wiseman ALA, Hutchinson JR. Walking-and Running and Jumping-with Dinosaurs and Their Cousins, Viewed Through the Lens of Evolutionary Biomechanics. Integr Comp Biol 2022; 62:icac049. [PMID: 35595475 DOI: 10.1093/icb/icac049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Archosauria diversified throughout the Triassic Period before experiencing two mass extinctions near its end ∼201 Mya, leaving only the crocodile-lineage (Crocodylomorpha) and bird-lineage (Dinosauria) as survivors; along with the pterosaurian flying reptiles. About 50 years ago, the "locomotor superiority hypothesis" (LSH) proposed that dinosaurs ultimately dominated by the Early Jurassic Period because their locomotion was superior to other archosaurs'. This idea has been debated continuously since, with taxonomic and morphological analyses suggesting dinosaurs were "lucky" rather than surviving due to being biologically superior. However, the LSH has never been tested biomechanically. Here we present integration of experimental data from locomotion in extant archosaurs with inverse and predictive simulations of the same behaviours using musculoskeletal models, showing that we can reliably predict how extant archosaurs walk, run and jump. These simulations have been guiding predictive simulations of extinct archosaurs to estimate how they moved, and we show our progress in that endeavour. The musculoskeletal models used in these simulations can also be used for simpler analyses of form and function such as muscle moment arms, which inform us about more basic biomechanical similarities and differences between archosaurs. Placing all these data into an evolutionary and biomechanical context, we take a fresh look at the LSH as part of a critical review of competing hypotheses for why dinosaurs (and a few other archosaur clades) survived the Late Triassic extinctions. Early dinosaurs had some quantifiable differences in locomotor function and performance vs. some other archosaurs, but other derived dinosaurian features (e.g., metabolic or growth rates, ventilatory abilities) are not necessarily mutually exclusive from the LSH; or maybe even an opportunistic replacement hypothesis; in explaining dinosaurs' success.
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Affiliation(s)
- A R Cuff
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, United Kingdom
- Human Anatomy Resource Centre, University of Liverpool, Liverpool, United Kingdom
| | - O E Demuth
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, United Kingdom
- Department of Earth Sciences, University of Cambridge, United Kingdom
| | - K Michel
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, United Kingdom
| | - A Otero
- CONICET - División Paleontología de Vertebrados, Facultad de Ciencias Naturales y Museo, Anexo Laboratorios, La Plata, Argentina
| | - R Pintore
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, United Kingdom
- Mécanismes adaptatifs et évolution (MECADEV) / UMR 7179, CNRS / Muséum National d'Histoire Naturelle, France
| | - D T Polet
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, United Kingdom
| | - A L A Wiseman
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, United Kingdom
- McDonald Institute for Archaeological Research, University of Cambridge, United Kingdom
| | - J R Hutchinson
- Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, Royal Veterinary College, United Kingdom
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Demuth OE, Benito J, Tschopp E, Lautenschlager S, Mallison H, Heeb N, Field DJ. Topology-Based Three-Dimensional Reconstruction of Delicate Skeletal Fossil Remains and the Quantification of Their Taphonomic Deformation. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.828006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Taphonomic and diagenetic processes inevitably distort the original skeletal morphology of fossil vertebrate remains. Key aspects of palaeobiological datasets may be directly impacted by such morphological deformation, such as taxonomic diagnoses and phylogenetic hypotheses, interpretations of the shape and orientation of anatomical structures, and assessments of interspecific and intraspecific variation. In order to overcome these ubiquitous challenges we present a novel reconstruction workflow combining retopology and retrodeformation, allowing the original morphology of both symmetrically and asymmetrically damaged areas of fossils to be reconstructed. As case studies, we present idealised three-dimensional reconstructions of the sternum of the crownward stem-bird Ichthyornis dispar, and cervical vertebrae of the diplodocid sauropod Galeamopus pabsti. Multiple Ichthyornis sterna were combined into a single, idealised composite representation through superimposition and alignment of retopologised models, and this composite was subsequently retrodeformed. The Galeamopus vertebrae were individually retrodeformed and symmetrised. Our workflow enabled us to quantify deformation of individual specimens with respect to our reconstructions, and to characterise global and local taphonomic deformation. Our workflow can be integrated with geometric morphometric approaches to enable quantitative morphological comparisons among multiple specimens, as well as quantitative interpolation of “mediotypes” of serially homologous elements such as missing vertebrae, haemal arches, or ribs.
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Wiseman ALA, Demuth OE, Hutchinson JR. A Guide to Inverse Kinematic Marker-Guided Rotoscoping using IK Solvers. Integr Org Biol 2022; 4:obac002. [PMID: 35261964 PMCID: PMC8896983 DOI: 10.1093/iob/obac002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
X-ray Reconstruction of Moving Morphology (XROMM) permits researchers to see beneath the skin, usually to see musculoskeletal movements. These movements can be tracked and later used to provide information regarding the mechanics of movement. Here, we discuss “IK marker-guided rotoscoping”—a method that combines inverse kinematic solvers with that of traditional scientific rotoscoping methods to quickly and efficiently overlay 3D bone geometries with the X-ray shadows from XROMM data. We use a case study of three Nile crocodiles’ (Crocodylus niloticus) forelimbs and hindlimbs to evaluate this method. Within these limbs, different marker configurations were used: some configurations had six markers, others had five markers, and all forelimb data only had three markers. To evaluate IK marker-guided rotoscoping, we systematically remove markers in the six-marker configuration and then test the magnitudes of deviation in translations and rotations of the rigged setup with fewer markers versus those of the six-marker configuration. We establish that IK marker-guided rotoscoping is a suitable method for “salvaging” data that may have too few markers.
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Affiliation(s)
- Ashleigh L A Wiseman
- Structure and Motion Laboratory, Comparative Biomedical Sciences, Royal Veterinary College, Hatfield, UK
- McDonald Institute for Archaeological Research, University of Cambridge, Cambridge, UK
| | - Oliver E Demuth
- Structure and Motion Laboratory, Comparative Biomedical Sciences, Royal Veterinary College, Hatfield, UK
- Department of Earth Sciences, University of Cambridge, Cambridge, UK
| | - John R Hutchinson
- Structure and Motion Laboratory, Comparative Biomedical Sciences, Royal Veterinary College, Hatfield, UK
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Zwafing M, Lautenschlager S, Demuth OE, Nyakatura JA. Modeling Sprawling Locomotion of the Stem Amniote Orobates: An Examination of Hindlimb Muscle Strains and Validation Using Extant Caiman. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.659039] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The stem amniote Orobates pabsti has been reconstructed to be capable of relatively erect, balanced, and mechanically power-saving terrestrial locomotion. This suggested that the evolution of such advanced locomotor capabilities preceded the origin of crown-group amniotes. We here further investigate plausible body postures and locomotion of Orobates by taking soft tissues into account. Freely available animation software BLENDER is used to first reconstruct the lines of action of hindlimb adductors and retractors for Orobates and then estimate the muscle strain of these muscles. We experimentally varied different body heights in modeled hindlimb stride cycles of Orobates to find the posture that maximizes optimal strains over the course of a stride cycle. To validate our method, we used Caiman crocodilus. We replicated the identical workflow used for the analysis of Orobates and compared the locomotor posture predicted for Caiman based on muscle strain analysis with this species’ actual postural data known from a previously published X-ray motion analysis. Since this validation experiment demonstrated a close match between the modeled posture that maximizes optimal adductor and retractor muscle strain and the in vivo posture employed by Caiman, using the same method for Orobates was justified. Generally, the use of muscle strain analysis for the reconstruction of posture in quadrupedal vertebrate fossils thus appears a promising approach. Nevertheless, results for Orobates remained inconclusive as several postures resulted in similar muscle strains and none of the postures could be entirely excluded. These results are not in conflict with the previously inferred moderately erect locomotor posture of Orobates and suggest considerable variability of posture during locomotion.
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Wiseman ALA, Bishop PJ, Demuth OE, Cuff AR, Michel KB, Hutchinson JR. Musculoskeletal modelling of the Nile crocodile (Crocodylus niloticus) hindlimb: Effects of limb posture on leverage during terrestrial locomotion. J Anat 2021; 239:424-444. [PMID: 33754362 PMCID: PMC8273584 DOI: 10.1111/joa.13431] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 03/02/2021] [Accepted: 03/04/2021] [Indexed: 12/11/2022] Open
Abstract
We developed a three-dimensional, computational biomechanical model of a juvenile Nile crocodile (Crocodylus niloticus) pelvis and hindlimb, composed of 47 pelvic limb muscles, to investigate muscle function. We tested whether crocodiles, which are known to use a variety of limb postures during movement, use limb orientations (joint angles) that optimise the moment arms (leverages) or moment-generating capacities of their muscles during different limb postures ranging from a high walk to a sprawling motion. We also describe the three-dimensional (3D) kinematics of the crocodylian hindlimb during terrestrial locomotion across an instrumented walkway and a treadmill captured via X-ray Reconstruction of Moving Morphology (biplanar fluoroscopy; 'XROMM'). We reconstructed the 3D positions and orientations of each of the hindlimb bones and used dissection data for muscle lines of action to reconstruct a focal, subject-specific 3D musculoskeletal model. Motion data for different styles of walking (a high, crouched, bended and two types of sprawling motion) were fed into the 3D model to identify whether any joints adopted near-optimal poses for leverage across each of the behaviours. We found that (1) the hip adductors and knee extensors had their largest leverages during sprawling postures and (2) more erect postures typically involved greater peak moment arms about the hip (flexion-extension), knee (flexion) and metatarsophalangeal (flexion) joints. The results did not fully support the hypothesis that optimal poses are present during different locomotory behaviours because the peak capacities were not always reached around mid-stance phase. Furthermore, we obtained few clear trends for isometric moment-generating capacities. Therefore, perhaps peak muscular leverage in Nile crocodiles is instead reached either in early/late stance or possibly during swing phase or other locomotory behaviours that were not studied here, such as non-terrestrial movement. Alternatively, our findings could reflect a trade-off between having to execute different postures, meaning that hindlimb muscle leverage is not optimised for any singular posture or behaviour. Our model, however, provides a comprehensive set of 3D estimates of muscle actions in extant crocodiles which can form a basis for investigating muscle function in extinct archosaurs.
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Affiliation(s)
- Ashleigh L A Wiseman
- Structure and Motion Laboratory, Comparative Biomedical Sciences, Royal Veterinary College, Hatfield, UK
| | - Peter J Bishop
- Structure and Motion Laboratory, Comparative Biomedical Sciences, Royal Veterinary College, Hatfield, UK.,Geosciences Program, Queensland Museum, Brisbane, Qld, Australia.,Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, USA
| | - Oliver E Demuth
- Structure and Motion Laboratory, Comparative Biomedical Sciences, Royal Veterinary College, Hatfield, UK.,Department of Earth Sciences, University of Cambridge, Cambridge, UK
| | - Andrew R Cuff
- Structure and Motion Laboratory, Comparative Biomedical Sciences, Royal Veterinary College, Hatfield, UK.,Hull York Medical School, University of York, York, UK
| | - Krijn B Michel
- Structure and Motion Laboratory, Comparative Biomedical Sciences, Royal Veterinary College, Hatfield, UK
| | - John R Hutchinson
- Structure and Motion Laboratory, Comparative Biomedical Sciences, Royal Veterinary College, Hatfield, UK
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