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Bertozzo F, Stein K, Varotto E, Galassi FM, Ruffell A, Murphy E. Histological analysis and etiology of a pathological iguanodontian femur from England. J Anat 2024; 245:490-500. [PMID: 38726991 PMCID: PMC11306762 DOI: 10.1111/joa.14053] [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: 01/12/2023] [Revised: 04/15/2024] [Accepted: 04/15/2024] [Indexed: 08/09/2024] Open
Abstract
Derived ornithopods, such as hadrosaurids, show a high occurrence of fossilized lesions and diseases. However, paleopathologies in iguanodontians seem to be less common, considering the rich fossil record of these taxa in Europe, in particular in Belgium, Britain and Spain. Here, we describe an iguanodontian femur discovered in England that exhibits a large overgrowth of its lateral aspect, not previously recognized in any other similar remains. The specimen was scanned with micro-computed tomography (microCT) and later sectioned in three sites of the overgrowth for histological analysis. The femur belongs to an early adult Iguanodontia indet., based on the presence of a woven parallel fibered complex in the outer cortex and three to four lines of arrested growth. Internal analysis of the dome-like overgrowth suggests it can be diagnosed as a fracture callus. The injury might have negatively impacted upon the animal's locomotion as the trauma had occurred in the region above the knee, a crucial spot for hindlimb musculature. Finally, a cancellous medullary bone-like tissue was recognized in the medullary cavity next to the pathological overgrowth. An attempt was made to determine the precise nature of this tissue, as medullary bone is linked with the ovulation period in (avian) dinosaurs, whereas other types of endosteal, medullary bone-like tissue have previously been recognized in pathological bones.
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Affiliation(s)
- Filippo Bertozzo
- Operational Directorate Earth and History of Life, Royal Belgian Institute of Natural Sciences, Brussels, Belgium
- Sociedade de Historia Natural, Torres Vedras, Portugal
| | - Koen Stein
- Vrije Universiteit Brussel, Brussels, Belgium
| | - Elena Varotto
- Archaeology, College of Humanities, Arts and Social Sciences, Flinders University, Adelaide, South Australia, Australia
- FAPAB Research Center, Avola (SR), Sicily, Italy
| | - Francesco M Galassi
- Department of Anthropology, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland
| | - Alastair Ruffell
- School of Natural and Built Environment, Queen's University Belfast, Belfast, Northern Ireland, UK
| | - Eileen Murphy
- School of Natural and Built Environment, Queen's University Belfast, Belfast, Northern Ireland, UK
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2
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Griffin BW, Martin-Silverstone E, Pêgas RV, Meilak EA, Costa FR, Palmer C, Rayfield EJ. Modelling take-off moment arms in an ornithocheiraean pterosaur. PeerJ 2024; 12:e17678. [PMID: 39119105 PMCID: PMC11308997 DOI: 10.7717/peerj.17678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 06/12/2024] [Indexed: 08/10/2024] Open
Abstract
Take-off is a vital part of powered flight which likely constrains the size of birds, yet extinct pterosaurs are known to have reached far larger sizes. Three different hypothesised take-off motions (bipedal burst launching, bipedal countermotion launching, and quadrupedal launching) have been proposed as explanations for how pterosaurs became airborne and circumvented this proposed morphological limit. We have constructed a computational musculoskeletal model of a 5 m wingspan ornithocheiraean pterosaur, reconstructing thirty-four key muscles to estimate the muscle moment arms throughout the three hypothesised take-off motions. Range of motion constrained hypothetical kinematic sequences for bipedal and quadrupedal take-off motions were modelled after extant flying vertebrates. Across our simulations we did not find higher hindlimb moment arms for bipedal take-off motions or noticeably higher forelimb moment arms in the forelimb for quadrupedal take-off motions. Despite this, in all our models we found the muscles utilised in the quadrupedal take-off have the largest total launch applicable moment arms throughout the entire take-off sequences and for the take-off pose. This indicates the potential availability of higher leverage for a quadrupedal take-off than hypothesised bipedal motions in pterosaurs pending further examination of muscle forces.
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Affiliation(s)
- Benjamin W. Griffin
- Palaeobiology Group, School of Earth Sciences, University of Bristol, Bristol, United Kingdom
- School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | | | - Rodrigo V. Pêgas
- Laboratory of Vertebrate Paleontology and Animal Behavior. Federal University of ABC, Alameda da Universidade, São Bernardo do Campo, SP, Brazil
| | - Erik Anthony Meilak
- School of Pharmacy and Bioengineering, University of Keele, Keele, United Kingdom
| | - Fabiana R. Costa
- Laboratory of Vertebrate Paleontology and Animal Behavior. Federal University of ABC, Alameda da Universidade, São Bernardo do Campo, SP, Brazil
| | - Colin Palmer
- Palaeobiology Group, School of Earth Sciences, University of Bristol, Bristol, United Kingdom
| | - Emily J. Rayfield
- Palaeobiology Group, School of Earth Sciences, University of Bristol, Bristol, United Kingdom
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3
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Cerroni MA, Otero A, Novas FE. Appendicular myology of Skorpiovenator bustingorryi: A first attempt to reconstruct pelvic and hindlimb musculature in an abelisaurid theropod. Anat Rec (Hoboken) 2024. [PMID: 38989612 DOI: 10.1002/ar.25532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 06/05/2024] [Accepted: 06/20/2024] [Indexed: 07/12/2024]
Abstract
We present the pelvic and hindlimb musculature of the abelisaurid Skorpiovenator bustingorryi, constituting the most comprehensive muscle reconstruction to date in ceratosaur theropods. Using extant phylogenetic bracket method, we reconstructed 39 muscles that can commonly found in extant archosaurs. Through the identification of bone correlates, we recognized thigh and hindlimb muscles including knee extensors, m. iliofibularis, m. flexor tibialis externus, mm. caudofemorales, mm. puboischiofemorales, and crus muscles important in foot extension and flexion (e.g., m. tibialis anterior, mm. gastrocnemii). Also, autopodial intrinsic muscles were reconstructed whose function involve extension (m. extensor digiti 2-4), flexion (mm. flexor digitorum brevis superficialis), interdigital adduction (m. interosseus dorsalis) and abduction (m. interosseous plantaris, m. abductor 4). Abelisaurids like Skorpiovenator show a deep pre- and postacetabular blade of the ilia and enlarged cnemial crests, which would have helped increasing the moment arm of muscles related to hip flexion and hindlimb extension. Also, pedal muscles related to pronation were probably present but reduced (e.g., m. pronator profundus). Despite some gross differences in the autopodial morphology in extant outgroups (e.g., crocodilian metatarsus and avian tarsometatarsus), the present study allows us to hypothesize several pedal muscles in Skorpiovenator. These muscles would not be arranged in tendinous bundles as in Neornithes, but rather the condition would be similar to that of crocodilians with several layers formed by fleshy bellies on the plantar and dorsal aspects of the metatarsus. The musculature of Skorpiovenator is key for future studies concerning abelisaurid biomechanics, including the integration of functional morphology and ichnological data.
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Affiliation(s)
- Mauricio A Cerroni
- Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", Buenos Aires, Argentina
| | - Alejandro Otero
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
- División Paleontología de Vertebrados (Anexo Laboratorios), Museo de La Plata, La Plata, Argentina
| | - Fernando E Novas
- Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", Buenos Aires, Argentina
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4
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Bishop PJ, Pierce SE. The fossil record of appendicular muscle evolution in Synapsida on the line to mammals: Part II-Hindlimb. Anat Rec (Hoboken) 2024; 307:1826-1896. [PMID: 37727023 DOI: 10.1002/ar.25310] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 07/15/2023] [Accepted: 08/08/2023] [Indexed: 09/21/2023]
Abstract
This paper is the second in a two-part series that charts the evolution of appendicular musculature along the mammalian stem lineage, drawing upon the exceptional fossil record of extinct synapsids. Here, attention is focused on muscles of the hindlimb. Although the hindlimb skeleton did not undergo as marked a transformation on the line to mammals as did the forelimb skeleton, the anatomy of extant tetrapods indicates that major changes to musculature have nonetheless occurred. To better understand these changes, this study surveyed the osteological evidence for muscular attachments in extinct mammalian and nonmammalian synapsids, two extinct amniote outgroups, and a large selection of extant mammals, saurians, and salamanders. Observations were integrated into an explicit phylogenetic framework, comprising 80 character-state complexes covering all muscles crossing the hip, knee, and ankle joints. These were coded for 33 operational taxonomic units spanning >330 Ma of tetrapod evolution, and ancestral state reconstruction was used to evaluate the sequence of muscular evolution along the stem lineage from Amniota to Theria. The evolutionary history of mammalian hindlimb musculature was complex, nonlinear, and protracted, with several instances of convergence and pulses of anatomical transformation that continued well into the crown group. Numerous traits typically regarded as characteristically "mammalian" have much greater antiquity than previously recognized, and for some traits, most synapsids are probably more reflective of the ancestral amniote condition than are extant saurians. More broadly, this study highlights the utility of the fossil record in interpreting the evolutionary appearance of distinctive anatomies.
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Affiliation(s)
- Peter J Bishop
- Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
- Geosciences Program, Queensland Museum, Brisbane, Queensland, Australia
| | - Stephanie E Pierce
- Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
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5
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Bishop PJ, Pierce SE. The fossil record of appendicular muscle evolution in Synapsida on the line to mammals: Part I-Forelimb. Anat Rec (Hoboken) 2024; 307:1764-1825. [PMID: 37726984 DOI: 10.1002/ar.25312] [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: 03/17/2023] [Revised: 07/15/2023] [Accepted: 08/08/2023] [Indexed: 09/21/2023]
Abstract
This paper is the first in a two-part series that charts the evolution of appendicular musculature along the mammalian stem lineage, drawing upon the exceptional fossil record of extinct synapsids. Here, attention is focused on muscles of the forelimb. Understanding forelimb muscular anatomy in extinct synapsids, and how this changed on the line to mammals, can provide important perspective for interpreting skeletal and functional evolution in this lineage, and how the diversity of forelimb functions in extant mammals arose. This study surveyed the osteological evidence for muscular attachments in extinct mammalian and nonmammalian synapsids, two extinct amniote outgroups, and a large selection of extant mammals, saurians, and salamanders. Observations were integrated into an explicit phylogenetic framework, comprising 73 character-state complexes covering all muscles crossing the shoulder, elbow, and wrist joints. These were coded for 33 operational taxonomic units spanning >330 Ma of tetrapod evolution, and ancestral state reconstruction was used to evaluate the sequence of muscular evolution along the stem lineage from Amniota to Theria. In addition to producing a comprehensive documentation of osteological evidence for muscle attachments in extinct synapsids, this work has clarified homology hypotheses across disparate taxa and helped resolve competing hypotheses of muscular anatomy in extinct species. The evolutionary history of mammalian forelimb musculature was a complex and nonlinear narrative, punctuated by multiple instances of convergence and concentrated phases of anatomical transformation. More broadly, this study highlights the great insight that a fossil-based perspective can provide for understanding the assembly of novel body plans.
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Affiliation(s)
- Peter J Bishop
- Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
- Geosciences Program, Queensland Museum, Brisbane, Queensland, Australia
| | - Stephanie E Pierce
- Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
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6
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Pereyra ME, Cerroni MA, Lecuona A, Bona P, Fernández Dumont ML, Otero A. Hindlimb and pelvic anatomy of Caiman yacare (Archosauria, Pseudosuchia): Myology and osteological correlates with emphasis on lower leg and autopodial musculature. J Anat 2024; 244:749-791. [PMID: 38104997 PMCID: PMC11021681 DOI: 10.1111/joa.13995] [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: 06/22/2023] [Revised: 10/19/2023] [Accepted: 11/28/2023] [Indexed: 12/19/2023] Open
Abstract
The anatomy of the archosaurian pelvis and hindlimb has adopted a diversity of successful configurations allowing a wide range of postures during the evolution of the group (e.g., erect, sprawling). For this reason, thorough studies of the structure and function of the pelvic and hindlimb musculature of crocodylians are required and provide the possibility to expand their implications for the evolution of archosaurian locomotion, as well as to identify potential new characters based on muscles and their bony correlates. In this study, we give a detailed description of the pelvic and hindlimb musculature of the South American alligator Caiman yacare, providing comprehensive novel information regarding lower limb and autopodial muscles. Particularly for the pedal muscles, we propose a new classification for the dorsal and ventral muscles of the autopodium based on the organisation of these muscles in successive layers. We have studied the myology in a global background in which we have compared the Caiman yacare musculature with other crocodylians. In this sense, differences in the arrangement of m. flexor tibialis internus 1, m. flexor tibialis externus, m. iliofibularis, mm. puboischiofemorales internii 1 and 2, between Ca. yacare and other crocodylians were found. We also discuss the muscle attachments that have different bony correlates among the crocodylian species and their morphological variation. Most of the correlates did not exhibit great variation among the species compared. The majority of the recognised correlates were identified in the pelvic girdle; additionally, some bony correlates associated with the pedal muscles are highlighted here for the first time. This research provides a wide framework for future studies on comparative anatomy and functional morphology, which could contribute to improving the character definition used in phylogenetic analyses and to understand the patterns of musculoskeletal hindlimb evolution.
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Affiliation(s)
- Maria Eugenia Pereyra
- Consejo Nacional de Investigaciones Científicas y Técnicas-CONICET, Buenos Aires, Argentina
- División Paleontología Vertebrados, Anexo Laboratorios, Facultad de Ciencias Naturales y Museo, La Plata, Buenos Aires, Argentina
- Department of Biological Sciences, University of Cape Town, Rhodes Gift, South Africa
| | - Mauricio A Cerroni
- Consejo Nacional de Investigaciones Científicas y Técnicas-CONICET, Buenos Aires, Argentina
- Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales 'Bernardino Rivadavia', Buenos Aires, Argentina
| | - Agustina Lecuona
- Universidad Nacional de Río Negro, Instituto de Investigación en Paleobiología y Geología, General Roca, Río Negro, Argentina
- CONICET, Instituto de Investigación en Paleobiología y Geología (IIPG), General Roca, Río Negro, Argentina
| | - Paula Bona
- Consejo Nacional de Investigaciones Científicas y Técnicas-CONICET, Buenos Aires, Argentina
- División Paleontología Vertebrados, Anexo Laboratorios, Facultad de Ciencias Naturales y Museo, La Plata, Buenos Aires, Argentina
| | - M Lucila Fernández Dumont
- Consejo Nacional de Investigaciones Científicas y Técnicas-CONICET, Buenos Aires, Argentina
- Fundación de Historia Natural Félix de Azara, Centro de Ciencias Naturales Ambientales y Antropológicas, Universidad Maimónides, CONICET, Buenos Aires, Argentina
| | - Alejandro Otero
- Consejo Nacional de Investigaciones Científicas y Técnicas-CONICET, Buenos Aires, Argentina
- División Paleontología Vertebrados, Anexo Laboratorios, Facultad de Ciencias Naturales y Museo, La Plata, Buenos Aires, Argentina
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7
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Lacerda MBS, Bittencourt JS, Hutchinson JR. Reconstruction of the pelvic girdle and hindlimb musculature of the early tetanurans Piatnitzkysauridae (Theropoda, Megalosauroidea). J Anat 2024; 244:557-593. [PMID: 38037880 PMCID: PMC10941590 DOI: 10.1111/joa.13983] [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: 06/15/2023] [Revised: 11/10/2023] [Accepted: 11/15/2023] [Indexed: 12/02/2023] Open
Abstract
Piatnitzkysauridae were Jurassic theropods that represented the earliest diverging branch of Megalosauroidea, being one of the earliest lineages to have evolved moderate body size. This clade's typical body size and some unusual anatomical features raise questions about locomotor function and specializations to aid in body support; and other palaeobiological issues. Biomechanical models and simulations can illuminate how extinct animals may have moved, but require anatomical data as inputs. With a phylogenetic context, osteological evidence, and neontological data on anatomy, it is possible to infer the musculature of extinct taxa. Here, we reconstructed the hindlimb musculature of Piatnitzkysauridae (Condorraptor, Marshosaurus, and Piatnitzkysaurus). We chose this clade for future usage in biomechanics, for comparisons with myological reconstructions of other theropods, and for the resulting evolutionary implications of our reconstructions; differential preservation affects these inferences, so we discuss these issues as well. We considered 32 muscles in total: for Piatnitzkysaurus, the attachments of 29 muscles could be inferred based on the osteological correlates; meanwhile, in Condorraptor and Marshosaurus, we respectively inferred 21 and 12 muscles. We found great anatomical similarity within Piatnitzkysauridae, but differences such as the origin of M. ambiens and size of M. caudofemoralis brevis are present. Similarities were evident with Aves, such as the division of the M. iliofemoralis externus and M. iliotrochantericus caudalis and a broad depression for the M. gastrocnemius pars medialis origin on the cnemial crest. Nevertheless, we infer plesiomorphic features such as the origins of M. puboischiofemoralis internus 1 around the "cuppedicus" fossa and M. ischiotrochantericus medially on the ischium. As the first attempt to reconstruct muscles in early tetanurans, our study allows a more complete understanding of myological evolution in theropod pelvic appendages.
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Affiliation(s)
- Mauro B. S. Lacerda
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesThe Royal Veterinary CollegeHatfieldUK
- Pós‐Graduação em ZoologiaInstituto de Ciências Biológicas, Universidade Federal de Minas GeraisBelo HorizonteBrazil
| | - Jonathas S. Bittencourt
- Departamento de GeologiaInstituto de Geociências, Universidade Federal de Minas GeraisBelo HorizonteBrazil
| | - John R. Hutchinson
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesThe Royal Veterinary CollegeHatfieldUK
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8
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Anderson L, Brassey C, Pond S, Bates K, Sellers WI. Investigating the quadrupedal abilities of Scutellosaurus lawleri and its implications for locomotor behavior evolution among dinosaurs. Anat Rec (Hoboken) 2023; 306:2514-2536. [PMID: 36896818 DOI: 10.1002/ar.25189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 01/19/2023] [Accepted: 02/08/2023] [Indexed: 03/11/2023]
Abstract
A reversion to secondary quadrupedality is exceptionally rare in nature, yet the convergent re-evolution of this locomotor style occurred at least four separate times within Dinosauria. Facultative quadrupedality, an intermediate state between obligate bipedality and obligate quadrupedality, may have been an important transitional step in this locomotor shift, and is proposed for a range of basal ornithischians and sauropodomorphs. Advances in virtual biomechanical modeling and simulation have allowed for the investigation of limb anatomy and function in a range of extinct dinosaurian species, yet this technique has not been widely applied to explore facultatively quadrupedal gait generation. This study places its focus on Scutellosaurus, a basal thyreophoran that has previously been described as both an obligate biped and a facultative quadruped. The functional anatomy of the musculoskeletal system (myology, mass properties, and joint ranges of motion) has been reconstructed using extant phylogenetic bracketing and comparative anatomical datasets. This information was used to create a multi-body dynamic locomotor simulation that demonstrates that whil quadrupedal gaits were physically possible, they did not outperform bipedal gaits is any tested metric. Scutellosaurus cannot therefore be described as an obligate biped, but we would predict its use of quadrupedality would be very rare, and perhaps restricted to specific activities such as foraging. This finding suggests that basal thyreophorans are still overwhelmingly bipedal but is perhaps indicative of an adaptive pathway for later evolution of quadrupedality.
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9
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Pritchard AC, Irmis RB, Olori JC, Nesbitt SJ, Smith ND, Stocker MR, Turner AH. The femora of Drepanosauromorpha (Reptilia: Diapsida): Implications for the functional evolution of the thigh of Sauropsida. Anat Rec (Hoboken) 2023. [PMID: 36847780 DOI: 10.1002/ar.25160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/29/2022] [Accepted: 12/30/2022] [Indexed: 03/01/2023]
Abstract
The femora of diapsids have undergone morphological changes related to shifts in postural and locomotor modes, such as the transition from plesiomorphic amniote and diapsid taxa to the apomorphic conditions related to a more erect posture within Archosauriformes. One remarkable clade of Triassic diapsids is the chameleon-like Drepanosauromorpha. This group is known from numerous articulated but heavily compressed skeletons that have the potential to further inform early reptile femoral evolution. For the first time, we describe the three-dimensional osteology of the femora of Drepanosauromorpha, based on undistorted fossils from the Upper Triassic Chinle Formation and Dockum Group of North America. We identify apomorphies and a combination of character states that link these femora to those in crushed specimens of drepanosauromorphs and compare our sample with a range of amniote taxa. Several characteristics of drepanosauromorph femora, including a hemispherical proximal articular surface, prominent asymmetry in the proximodistal length of the tibial condyles, and a deep intercondylar sulcus, are plesiomorphies shared with early diapsids. The femora contrast with those of most diapsids in lacking a crest-like, distally tapering internal trochanter. They bear a ventrolaterally positioned tuberosity on the femoral shaft, resembling the fourth trochanter in Archosauriformes. The reduction of an internal trochanter parallels independent reductions in therapsids and archosauriforms. The presence of a ventrolaterally positioned trochanter is also similar to that of chameleonid squamates. Collectively, these features demonstrate a unique femoral morphology for drepanosauromorphs, and suggest an increased capacity for femoral adduction and protraction relative to most other Permo-Triassic diapsids.
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Affiliation(s)
| | - Randall B Irmis
- Natural History Museum of Utah and Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah, USA
| | | | - Sterling J Nesbitt
- Virginia Museum of Natural History, Martinsville, Virginia, USA.,Virginia Tech, Blacksburg, Virginia, USA
| | - Nathan D Smith
- Natural History Museum of Los Angeles County, Los Angeles, California, USA
| | - Michelle R Stocker
- Virginia Museum of Natural History, Martinsville, Virginia, USA.,Virginia Tech, Blacksburg, Virginia, USA
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10
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Dempsey M, Maidment SCR, Hedrick BP, Bates KT. Convergent evolution of quadrupedality in ornithischian dinosaurs was achieved through disparate forelimb muscle mechanics. Proc Biol Sci 2023; 290:20222435. [PMID: 36722082 PMCID: PMC9890092 DOI: 10.1098/rspb.2022.2435] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The secondary evolution of quadrupedality from bipedal ancestry is a rare evolutionary transition in tetrapods yet occurred convergently at least three times within ornithischian dinosaurs. Despite convergently evolving quadrupedal gait, ornithischians exhibited variable anatomy, particularly in the forelimbs, which underwent a major functional change from assisting in foraging and feeding in bipeds to becoming principal weight-bearing components of the locomotor system in quadrupeds. Here, we use three-dimensional multi-body dynamics models to demonstrate quantitatively that different quadrupedal ornithischian clades evolved distinct forelimb musculature, particularly around the shoulder. We find that major differences in glenohumeral abduction-adduction and long axis rotation muscle leverages were key drivers of mechanical disparity, thereby refuting previous hypotheses about functional convergence in major clades. Elbow muscle leverages were also disparate across the major ornithischian lineages, although high elbow extension muscle leverages were convergent between most quadrupeds. Unlike in ornithischian hind limbs, where differences are more closely tied to functional similarity than phylogenetic relatedness, mechanical disparity in ornithischian forelimbs appears to have been shaped primarily by phylogenetic constraints. Differences in ancestral bipedal taxa within each clade may have resulted in disparate ecomorphological constraints on the evolutionary pathways driving divergence in their quadrupedal descendants.
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Affiliation(s)
- Matthew Dempsey
- Department of Musculoskeletal & Ageing Science, Institute of Life Course & Medical Sciences, University of Liverpool, The William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, UK,Department of Earth Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | | | - Brandon P. Hedrick
- Department of Biomedical Sciences, College of Veterinary Medicine, Cornell University, 930 Campus Road, Ithaca, NY 14853, USA
| | - Karl T. Bates
- Department of Musculoskeletal & Ageing Science, Institute of Life Course & Medical Sciences, University of Liverpool, The William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, UK
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11
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Cuff AR, Wiseman ALA, Bishop PJ, Michel KB, Gaignet R, Hutchinson JR. Anatomically grounded estimation of hindlimb muscle sizes in Archosauria. J Anat 2022; 242:289-311. [PMID: 36206401 PMCID: PMC9877486 DOI: 10.1111/joa.13767] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 08/26/2022] [Accepted: 08/31/2022] [Indexed: 02/01/2023] Open
Abstract
In vertebrates, active movement is driven by muscle forces acting on bones, either directly or through tendinous insertions. There has been much debate over how muscle size and force are reflected by the muscular attachment areas (AAs). Here we investigate the relationship between the physiological cross-sectional area (PCSA), a proxy for the force production of the muscle, and the AA of hindlimb muscles in Nile crocodiles and five bird species. The limbs were held in a fixed position whilst blunt dissection was carried out to isolate the individual muscles. AAs were digitised using a point digitiser, before the muscle was removed from the bone. Muscles were then further dissected and fibre architecture was measured, and PCSA calculated. The raw measures, as well as the ratio of PCSA to AA, were studied and compared for intra-observer error as well as intra- and interspecies differences. We found large variations in the ratio between AAs and PCSA both within and across species, but muscle fascicle lengths are conserved within individual species, whether this was Nile crocodiles or tinamou. Whilst a discriminant analysis was able to separate crocodylian and avian muscle data, the ratios for AA to cross-sectional area for all species and most muscles can be represented by a single equation. The remaining muscles have specific equations to represent their scaling, but equations often have a relatively high success at predicting the ratio of muscle AA to PCSA. We then digitised the muscle AAs of Coelophysis bauri, a dinosaur, to estimate the PCSAs and therefore maximal isometric muscle forces. The results are somewhat consistent with other methods for estimating force production, and suggest that, at least for some archosaurian muscles, that it is possible to use muscle AA to estimate muscle sizes. This method is complementary to other methods such as digital volumetric modelling.
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Affiliation(s)
- Andrew R. Cuff
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesRoyal Veterinary CollegeHatfieldUK,Human Anatomy Resource CentreUniversity of LiverpoolLiverpoolUK
| | - Ashleigh L. A. Wiseman
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesRoyal Veterinary CollegeHatfieldUK
| | - Peter J. Bishop
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesRoyal Veterinary CollegeHatfieldUK,Museum of Comparative Zoology and Department of Organismic and Evolutionary BiologyHarvard UniversityCambridgeUSA,Geosciences ProgramQueensland MuseumBrisbaneQueenslandAustralia
| | - Krijn B. Michel
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesRoyal Veterinary CollegeHatfieldUK
| | - Raphäelle Gaignet
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesRoyal Veterinary CollegeHatfieldUK
| | - John R. Hutchinson
- Structure and Motion Laboratory, Department of Comparative Biomedical SciencesRoyal Veterinary CollegeHatfieldUK
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12
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Moore BRS, Roloson MJ, Currie PJ, Ryan MJ, Patterson RT, Mallon JC. The appendicular myology of Stegoceras validum (Ornithischia: Pachycephalosauridae) and implications for the head-butting hypothesis. PLoS One 2022; 17:e0268144. [PMID: 36048811 PMCID: PMC9436104 DOI: 10.1371/journal.pone.0268144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 04/22/2022] [Indexed: 11/19/2022] Open
Abstract
In this study, we use an exceptional skeleton of the pachycephalosaur Stegoceras validum (UALVP 2) to inform a comprehensive appendicular muscle reconstruction of the animal, with the goal of better understanding the functional morphology of the pachycephalosaur postcranial skeleton. We find that S. validum possessed a conservative forelimb musculature, particularly in comparison to early saurischian bipeds. By contrast, the pelvic and hind limb musculature are more derived, reflecting peculiarities of the underlying skeletal anatomy. The iliotibialis, ischiocaudalis, and caudofemoralis muscles have enlarged attachment sites and the caudofemoralis has greater leverage owing to the distal displacement of the fourth trochanter along the femur. These larger muscles, in combination with the wide pelvis and stout hind limbs, produced a stronger, more stable pelvic structure that would have proved advantageous during hypothesized intraspecific head-butting contests. The pelvis may have been further stabilized by enlarged sacroiliac ligaments, which stemmed from the unique medial iliac flange of the pachycephalosaurs. Although the pubis of UALVP 2 is not preserved, the pubes of other pachycephalosaurs are highly reduced. The puboischiofemoralis musculature was likely also reduced accordingly, and compensated for by the aforementioned improved pelvic musculature.
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Affiliation(s)
- Bryan R. S. Moore
- Ottawa Carleton Geoscience Center and Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada
- * E-mail:
| | - Mathew J. Roloson
- Ottawa Carleton Geoscience Center and Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada
| | - Philip J. Currie
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Michael J. Ryan
- Ottawa Carleton Geoscience Center and Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada
- Beaty Centre for Species Discovery and Palaeobiology section, Canadian Museum of Nature, Ottawa, Ontario, Canada
| | - R. Timothy Patterson
- Ottawa Carleton Geoscience Center and Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada
| | - Jordan C. Mallon
- Ottawa Carleton Geoscience Center and Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada
- Beaty Centre for Species Discovery and Palaeobiology section, Canadian Museum of Nature, Ottawa, Ontario, Canada
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13
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Constraining pterosaur launch: range of motion in the pectoral and pelvic girdles of a medium-sized ornithocheiraean pterosaur. Biol J Linn Soc Lond 2022. [DOI: 10.1093/biolinnean/blac063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Launch is the most energetically expensive part of flight and is considered a limiting factor in the size of modern flyers. Pterosaurs reached significantly larger sizes than modern flyers and are proposed to have launched either bipedallly or quadrupedally. We investigated the ability of a medium-sized ornithocheiraean pterosaur to assume the poses required to launch bipedally or quadrupedally. We applied range of motion (ROM) mapping methodology to the pectoral and pelvic girdles to identify viable poses at varying levels of appendicular cartilage based on the extant phylogenetic bracket. The ROMs were constrained by novel triangulated minimum stretch methodology, used to identify the restraining tissue ROM. Our study indicates that a medium-sized ornithocheiraean could assume the poses required to use a quadrupedal launch and, with an additional 10° of hindlimb abduction, a bipedal launch, although further analysis is required to determine whether sufficient muscular power and leverage was available to propel the animal into the air.
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14
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Griffin CT, Botelho JF, Hanson M, Fabbri M, Smith-Paredes D, Carney RM, Norell MA, Egawa S, Gatesy SM, Rowe TB, Elsey RM, Nesbitt SJ, Bhullar BAS. The developing bird pelvis passes through ancestral dinosaurian conditions. Nature 2022; 608:346-352. [PMID: 35896745 DOI: 10.1038/s41586-022-04982-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 06/15/2022] [Indexed: 11/08/2022]
Abstract
Living birds (Aves) have bodies substantially modified from the ancestral reptilian condition. The avian pelvis in particular experienced major changes during the transition from early archosaurs to living birds1,2. This stepwise transformation is well documented by an excellent fossil record2-4; however, the ontogenetic alterations that underly it are less well understood. We used embryological imaging techniques to examine the morphogenesis of avian pelvic tissues in three dimensions, allowing direct comparison with the fossil record. Many ancestral dinosaurian features2 (for example, a forward-facing pubis, short ilium and pubic 'boot') are transiently present in the early morphogenesis of birds and arrive at their typical 'avian' form after transitioning through a prenatal developmental sequence that mirrors the phylogenetic sequence of character acquisition. We demonstrate quantitatively that avian pelvic ontogeny parallels the non-avian dinosaur-to-bird transition and provide evidence for phenotypic covariance within the pelvis that is conserved across Archosauria. The presence of ancestral states in avian embryos may stem from this conserved covariant relationship. In sum, our data provide evidence that the avian pelvis, whose early development has been little studied5-7, evolved through terminal addition-a mechanism8-10 whereby new apomorphic states are added to the end of a developmental sequence, resulting in expression8,11 of ancestral character states earlier in that sequence. The phenotypic integration we detected suggests a previously unrecognized mechanism for terminal addition and hints that retention of ancestral states in development is common during evolutionary transitions.
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Affiliation(s)
- Christopher T Griffin
- Department of Earth and Planetary Sciences, Yale University, New Haven, CT, USA
- Yale Peabody Museum of Natural History, Yale University, New Haven, CT, USA
- Department of Geosciences, Virginia Tech, Blacksburg, VA, USA
| | - João F Botelho
- Department of Earth and Planetary Sciences, Yale University, New Haven, CT, USA
- Yale Peabody Museum of Natural History, Yale University, New Haven, CT, USA
- Departamento Biología Celular y Molecular, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Michael Hanson
- Department of Earth and Planetary Sciences, Yale University, New Haven, CT, USA
- Yale Peabody Museum of Natural History, Yale University, New Haven, CT, USA
| | - Matteo Fabbri
- Department of Earth and Planetary Sciences, Yale University, New Haven, CT, USA
- Yale Peabody Museum of Natural History, Yale University, New Haven, CT, USA
- Nagaunee Integrative Research Center, Field Museum of Natural History, Chicago, IL, USA
| | - Daniel Smith-Paredes
- Department of Earth and Planetary Sciences, Yale University, New Haven, CT, USA
- Yale Peabody Museum of Natural History, Yale University, New Haven, CT, USA
| | - Ryan M Carney
- Department of Integrative Biology, University of South Florida, Tampa, FL, USA
| | - Mark A Norell
- Division of Vertebrate Paleontology, American Museum of Natural History, New York, NY, USA
| | - Shiro Egawa
- RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Stephen M Gatesy
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI, USA
| | - Timothy B Rowe
- Jackson School of Geosciences, The University of Texas at Austin, Austin, TX, USA
| | - Ruth M Elsey
- Rockefeller Wildlife Refuge, Louisiana Department of Wildlife and Fisheries, Grand Chenier, LA, USA
| | | | - Bhart-Anjan S Bhullar
- Department of Earth and Planetary Sciences, Yale University, New Haven, CT, USA.
- Yale Peabody Museum of Natural History, Yale University, New Haven, CT, USA.
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15
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Wosik M, Evans DC. Osteohistological and taphonomic life-history assessment of Edmontosaurus annectens (Ornithischia: Hadrosauridae) from the Late Cretaceous (Maastrichtian) Ruth Mason dinosaur quarry, South Dakota, United States, with implication for ontogenetic segregation between juvenile and adult hadrosaurids. J Anat 2022; 241:272-296. [PMID: 35801524 PMCID: PMC9296034 DOI: 10.1111/joa.13679] [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: 07/14/2021] [Revised: 04/11/2022] [Accepted: 04/12/2022] [Indexed: 11/28/2022] Open
Abstract
The Late Cretaceous (Maastrichtian) Ruth Mason Dinosaur Quarry (RMDQ) represents a monodominant Edmontosaurus annectens bonebed from the Hell Creek Formation of South Dakota and has been determined as a catastrophic death assemblage likely belonging to a single population, providing an ideal sample to investigate hadrosaurid growth and population dynamics. For this study, size-frequency distributions were constructed from linear measurements of long bones (humeri, femora, tibiae) from RMDQ that revealed five relatively distinct size classes along a generally right-skewed distribution, which is consistent with a catastrophic assemblage. To test the relationship between morphological size ranges and ontogenetic age classes, subsets from each size-frequency peak were transversely thin-sectioned at mid-diaphysis to conduct an ontogenetic age assessment based on growth marks and observations of the bone microstructure. When combining these independent datasets, growth marks aligned with size-frequency peaks, with the exclusion of the overlapping subadult-adult size range, indicating a strong size-age relationship in early ontogeny. A growth curve analysis of tibiae indicated that E. annectens exhibited a similar growth trajectory to the Campanian hadrosaurid Maiasaura, although attaining a much larger asymptotic body size by about 9 years of age, further suggesting that the clade as a whole may have inherited a similar growth strategy. This rich new dataset for E. annectens provides new perspectives on other hypotheses of hadrosaurid life history. When the RMDQ population was compared with size distributions from other hadrosaurid bonebed assemblages, juveniles (categorized as ages one and two) were either completely absent from or heavily underrepresented in the samples, providing support for the hypothesized segregation between juvenile and adult hadrosaurids. Osteohistological comparison with material from polar and temperate populations of Edmontosaurus revealed that previous conclusions correlating osteohistological growth patterns with the strength of environmental stressors were a result of sampling non-overlapping ontogenetic growth stages.
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Affiliation(s)
- Mateusz Wosik
- Department of BiologyMisericordia UniversityDallasPennsylvaniaUSA
- Department of Ecology and Evolutionary BiologyUniversity of TorontoTorontoOntarioCanada
- Department of Natural History, Royal Ontario MuseumTorontoOntarioCanada
| | - David C. Evans
- Department of Ecology and Evolutionary BiologyUniversity of TorontoTorontoOntarioCanada
- Department of Natural History, Royal Ontario MuseumTorontoOntarioCanada
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16
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Ballell A, Rayfield EJ, Benton MJ. Walking with early dinosaurs: appendicular myology of the Late Triassic sauropodomorph Thecodontosaurus antiquus. ROYAL SOCIETY OPEN SCIENCE 2022; 9:211356. [PMID: 35116154 PMCID: PMC8767213 DOI: 10.1098/rsos.211356] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 12/06/2021] [Indexed: 06/14/2023]
Abstract
Dinosaur evolution is marked by numerous independent shifts from bipedality to quadrupedality. Sauropodomorpha is one of the lineages that transitioned from small bipedal forms to graviportal quadrupeds, with an array of intermediate postural strategies evolving in non-sauropodan sauropodomorphs. This locomotor shift is reflected by multiple modifications of the appendicular skeleton, coupled with a drastic rearrangement of the limb musculature. Here, we describe the osteological correlates of appendicular muscle attachment of the Late Triassic sauropodomorph Thecodontosaurus antiquus from multiple well-preserved specimens and provide the first complete forelimb and hindlimb musculature reconstruction of an early-branching sauropodomorph. Comparisons with other sauropodomorphs and early dinosaurs reveal a unique combination of both plesiomorphic and derived musculoskeletal features. The diversity of appendicular osteological correlates among early dinosaurs and their relevance in muscle reconstruction are discussed. In line with previous evidence, aspects of the limb muscle arrangement, such as conspicuous correlates of lower limb extensors and flexors and low moment arms of hip extensors and flexors, suggest Thecodontosaurus was an agile biped. This reconstruction helps to elucidate the timing of important modifications of the appendicular musculature in the evolution of sauropodomorphs which facilitated the transition to quadrupedalism and contributed to their evolutionary success.
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Affiliation(s)
- Antonio Ballell
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Emily J. Rayfield
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Michael J. Benton
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
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17
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Diaz RE, Taylor-Diaz EA, Trainor PA, Diogo R, Molnar JL. Comparative development of limb musculature in phylogenetically and ecologically divergent lizards. Dev Dyn 2021; 251:1576-1612. [PMID: 34927301 DOI: 10.1002/dvdy.447] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 12/15/2021] [Accepted: 12/16/2021] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Squamate reptiles (lizards, snakes, and amphisbaenians) exhibit incredible diversity in their locomotion, behavior, morphology, and ecological breadth. Although they often are used as models of locomotor diversity, surprisingly little attention has been given to muscle development in squamate reptiles. In fact, the most detailed examination was conducted almost 80 years ago and solely focused on the proximal limb regions. Herein, we present forelimb and hindlimb muscle morphogenesis data for three lizard species with different locomotion and feeding strategies: the desert grassland whiptail lizard, the central bearded dragon, and the veiled chameleon. This study fills critical gaps in our understanding of muscle morphogenesis in squamate reptiles and presents a comparative and temporospatial analysis of muscle development. RESULTS Our results reveal a conserved pattern of early muscle development among lizards with different adult morphologies and ecologies. The variations that exist are concentrated in distal regions, particularly the specialized autopodia of chameleons, where differentiation of muscles associated with the digits is delayed. CONCLUSIONS The chameleon autopod provides an example of major evolutionary modifications to the skeleton with only minor disruption of the conserved order and pattern of limb muscle development. This robustness of muscle patterning facilitates the evolution of extreme yet functional phenotypes.
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Affiliation(s)
- Raul E Diaz
- Department of Biological Sciences, California State University, Los Angeles, California, USA.,Department of Herpetology, Natural History Museum of Los Angeles County, Los Angeles, California, USA
| | - Elizabeth A Taylor-Diaz
- Department of Biological Sciences, California State University, Los Angeles, California, USA
| | - Paul A Trainor
- Investigator, Stowers Institute for Medical Research, Kansas City, Missouri, USA.,Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Rui Diogo
- Department of Anatomy, Howard University College of Medicine, Washington, District of Columbia, USA
| | - Julia L Molnar
- Department of Anatomy, New York Institute of Technology, College of Osteopathic Medicine, Old Westbury, New York, USA
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18
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Koizumi M. Comparative anatomy of the subscapularis, teres major and latissimus dorsi muscles from salamanders to mammals with special reference to their innervations from the brachial plexus. Anat Sci Int 2021; 97:124-137. [PMID: 34677758 DOI: 10.1007/s12565-021-00636-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 10/08/2021] [Indexed: 11/25/2022]
Abstract
It has been reported that the ramification pattern of spinal motor nerves reflected the spatial orientation of motoneuron pools in the ventral horn of spinal cord and this topography of spinal motor nuclei was very similar in different vertebrates. Therefore, the ramification pattern of spinal nerves was an important criterion for discussing the phylogenetic homology of muscles. It has been reported that the human subscapularis muscle was innervated by several branches, the proximal branch of them was from the ventral layer of the dorsal cord and the distal one from the dorsal layer of the dorsal cord of the brachial plexus. This fact suggested the human subscapularis had different phylogenetic origins. In this study, I unveil the phylogenetic origin of the mammalian subscapularis. The animals observed were a chimpanzee, a lar gibbon, a cat, a fetal pig, a koala, a possum (mammals), a lizard, an iguana (reptiles) and salamanders (amphibians). The branches to the mammalian subscapularis were divided into proximal and distal groups based on the origin from the brachial plexus, just like the human subscapularis. In salamanders and lizards, the homologous branch with the mammalian proximal branch to the subscapularis was observed and the segmentally higher branch innervating the latissimus dorsi was homologous with the distal branch to the mammalian subscapularis. Conclusively, I suppose that the dorsal-most portion of the reptilian latissimus dorsi muscle differentiates to the mammalian teres major, and the segmentally higher portion of the reptilian latissimus dorsi contributes to the formation of the mammalian subscapularis.
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Affiliation(s)
- Masahiro Koizumi
- Tokyo Ariake University of Medical and Health Sciences, 2-9-1 Ariake, Koto-Ku, Tokyo, 135-0063, Japan.
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19
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Kobayashi Y, Takasaki R, Kubota K, Fiorillo AR. A new basal hadrosaurid (Dinosauria: Ornithischia) from the latest Cretaceous Kita-ama Formation in Japan implies the origin of hadrosaurids. Sci Rep 2021; 11:8547. [PMID: 33903622 PMCID: PMC8076177 DOI: 10.1038/s41598-021-87719-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 04/01/2021] [Indexed: 11/21/2022] Open
Abstract
Here we describe a partial hadrosaurid skeleton from the marine Maastrichtian Kita-ama Formation in Japan as a new taxon, Yamatosaurus izanagii gen. et sp. nov., based on unique characters in the dentition. Our phylogenetic analysis demonstrates Yamatosaurus izanagii belongs to Hadrosauridae, composed of Hadrosaurus foulkii + (Yamatosaurus izanagii + (Saurolophinae + Lambeosaurinae)). The coracoid lacks a biceps tubercle as in non-hadrosaurid hadrosauroids, suggesting its presence is a key feature for the clade of Saurolophinae and Lambeosaurinae. The evolutionary rates analysis further supports that shoulder and forelimb features, which are likely to have been involved in locomotion, were important for the early evolution of Hadrosauridae. Our biogeographic analyses show that basal hadrosaurids were widely distributed in Asia and Appalachia, that the clade of Saurolophinae and Lambeosaurinae originated in Asia, and that eastern Asia may have served as a refugium of relict hadrosauroid taxa such as Plesiohadros djadokhtaensis, Tanius sinensis, and Yamatosaurus izanagii during the Late Cretaceous. The contemporaneous occurrence of basal (Yamatosaurus izanagii) and derived (Kamuysaurus japonicus) hadrosaurids during the Maastrichtian in Japan is the first record in Asia. Because of the long geographical distance between these localities, they likely did not co-exist, but instead demonstrate some level of provinciality.
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Affiliation(s)
- Yoshitsugu Kobayashi
- Hokkaido University Museum, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan.
| | - Ryuji Takasaki
- Faculty of Biosphere-Geosphere Science, Okayama University of Science, Okayama, 700-0005, Japan
| | - Katsuhiro Kubota
- Hokkaido University Museum, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan
- Museum of Nature and Human Activities, Hyogo, Sanda, Hyogo, 669-1546, Japan
- Institute of Natural and Environmental Sciences, University of Hyogo, Sanda, Hyogo, 669-1546, Japan
| | - Anthony R Fiorillo
- Hokkaido University Museum, Hokkaido University, Sapporo, Hokkaido, 060-0810, Japan
- Institute for the Study of Earth and Man, Southern Methodist University, Dallas, TX, 75275, USA
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20
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Rhodes MM, Henderson DM, Currie PJ. Maniraptoran pelvic musculature highlights evolutionary patterns in theropod locomotion on the line to birds. PeerJ 2021; 9:e10855. [PMID: 33717681 PMCID: PMC7937347 DOI: 10.7717/peerj.10855] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 01/07/2021] [Indexed: 01/07/2023] Open
Abstract
Locomotion is a fundamental aspect of palaeobiology and often investigated by comparing osteological structures and proportions. Previous studies document a stepwise accumulation of avian-like features in theropod dinosaurs that accelerates in the clade Maniraptora. However, the soft tissues that influenced the skeleton offer another perspective on locomotory adaptations. Examination of the pelvis for osteological correlates of hind limb and tail musculature allowed reconstruction of primary locomotory muscles across theropods and their closest extant relatives. Additionally, the areas of pelvic muscle origins were quantified to measure relative differences within and between taxa, to compare morphological features associated with cursoriality, and offer insight into the evolution of locomotor modules. Locomotory inferences based on myology often corroborate those based on osteology, although they occasionally conflict and indicate greater complexity than previously appreciated. Maniraptoran pelvic musculature underscores previous studies noting the multifaceted nature of cursoriality and suggests that a more punctuated step in caudal decoupling occurred at or near the base of Maniraptora.
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Affiliation(s)
- Matthew M Rhodes
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | | | - Philip J Currie
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
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21
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Smith DK. Forelimb musculature and function in the therizinosaur Nothronychus (Maniraptora, Theropoda). J Anat 2021; 239:307-335. [PMID: 33665832 PMCID: PMC8273597 DOI: 10.1111/joa.13418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 02/12/2021] [Accepted: 02/15/2021] [Indexed: 11/28/2022] Open
Abstract
Therizinosaurs are unusual theropods from the Upper Cretaceous of Asia and North America. North American representatives include Falcarius utahensis from central Utah, Nothronychus mckinleyi from west central New Mexico, and N. graffami from southern Utah. Nothronychus was quite large, with well-developed forelimbs and pectoral girdle. In many respects, however, these structures were typical for conventional carnivorous theropods, although therizinosaurs have been hypothesized to be herbivorous using anatomical and functional inferences. There is no indication of increased range of motion within the forelimbs, as might be predicted for derived non-avian theropods. The muscular anatomy of the pectoral girdle and forelimb of Nothronychus is reconstructed using visible muscle scars, data from extant birds and crocodilians, and models for other theropods. The osteology and inferred musculature is a mosaic of primitive and derived characters for theropods. A fossa pneumotricipitales may have been present in the proximal humerus. There was a well-developed fossa brachialis in the distal humerus. The epicleidium of the furcula is deflected, reflecting either taphonomic deformation or possibly accommodation of M. supracoracoideus in a triosseal canal, but such a development has yet to be described in any non-avian theropod. In many respects, the other muscular results were quite similar to those inferred for dromaeosaurs.
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Affiliation(s)
- David K Smith
- Biology Department, Northland Pioneer College, Holbrook, AZ, USA
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22
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Voegele KK, Ullmann PV, Lamanna MC, Lacovara KJ. Myological reconstruction of the pelvic girdle and hind limb of the giant titanosaurian sauropod dinosaur Dreadnoughtus schrani. J Anat 2021; 238:576-597. [PMID: 33084085 PMCID: PMC7855065 DOI: 10.1111/joa.13334] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 08/26/2020] [Accepted: 09/21/2020] [Indexed: 01/21/2023] Open
Abstract
Osteological correlates preserve more readily than their soft tissue counterparts in the fossil record; therefore, they can more often provide insight into the soft tissue anatomy of the organism. These insights can in turn elucidate the biology of these extinct organisms. In this study, we reconstruct the pelvic girdle and hind limb musculature of the giant titanosaurian sauropod Dreadnoughtus schrani based on observations of osteological correlates and Extant Phylogenetic Bracket comparisons. Recovered fossils of Dreadnoughtus exhibit remarkably well-preserved, well-developed, and extensive muscle scars. Furthermore, this taxon is significantly larger bodied than any titanosaurian for which a myological reconstruction has previously been performed, rendering this contribution highly informative for the group. All 20 of the muscles investigated in this study are sufficiently well supported to enable reconstruction of at least one division, including reconstruction of the M. ischiocaudalis for the first time in a sauropod dinosaur. In total, 34 osteological correlates were identified on the pelvic girdle and hind limb remains of Dreadnoughtus, allowing the reconstruction of 14 muscles on the basis of Level I or Level II inferences (i.e., not Level I' or Level II' inferences). Comparisons among titanosaurians suggest widespread myological variation, yet potential phylogenetic and other paleobiologic patterns are often obscured by fragmentary preservation, infrequent myological studies, and lack of consensus on the phylogenetic placement of many taxa. However, a ventrolateral accessory process is present on the preacetabular lobe of the ilium in all of the largest titanosauriforms that preserve this skeletal element, suggesting that the presence of this process (representing the origin of the M. puboischiofemoralis internus part II) may be associated with extreme body size. By identifying such myological patterns among titanosauriforms, we can begin to address specific evolutionary and biomechanical questions related to their skeletal anatomy, how they were capable of leaving wide-gauge trackways, and resulting locomotor attributes unique to this clade.
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Affiliation(s)
| | | | - Matthew C. Lamanna
- Section of Vertebrate PaleontologyCarnegie Museum of Natural HistoryPittsburghPAUSA
| | - Kenneth J. Lacovara
- Department of GeologyRowan UniversityGlassboroNJUSA,School of Earth and EnvironmentRowan UniversityGlassboroNJUSA
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23
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Campbell RM, Vinas G, Henneberg M, Diogo R. Visual Depictions of Our Evolutionary Past: A Broad Case Study Concerning the Need for Quantitative Methods of Soft Tissue Reconstruction and Art-Science Collaborations. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.639048] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Flip through scientific textbooks illustrating ideas about human evolution or visit any number of museums of natural history and you will notice an abundance of reconstructions attempting to depict the appearance of ancient hominins. Spend some time comparing reconstructions of the same specimen and notice an obvious fact: hominin reconstructions vary in appearance considerably. In this review, we summarize existing methods of reconstruction to analyze this variability. It is argued that variability between hominin reconstructions is likely the result of unreliable reconstruction methods and misinterpretation of available evidence. We also discuss the risk of disseminating erroneous ideas about human evolution through the use of unscientific reconstructions in museums and publications. The role an artist plays is also analyzed and criticized given how the aforementioned reconstructions have become readily accepted to line the halls of even the most trusted institutions. In conclusion, improved reconstruction methods hold promise for the prediction of hominin soft tissues, as well as for disseminating current scientific understandings of human evolution in the future.
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Hattori S, Tsuihiji T. Homology and osteological correlates of pedal muscles among extant sauropsids. J Anat 2021; 238:365-399. [PMID: 32974897 PMCID: PMC7812136 DOI: 10.1111/joa.13307] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 07/22/2020] [Accepted: 08/12/2020] [Indexed: 12/04/2022] Open
Abstract
Archosaurs displayed an evolutionary trend toward increasing bipedalism in their evolutionary history, that is, forelimbs tend to be reduced in contrast to the development of hindlimbs becoming major weight-bearing and locomotor appendages. The archosaurian locomotion has been extensively discussed based on their limb morphology because the latter reflects their locomotor modes very well. However, despite some attempts of reconstructing the hindlimb musculature in Archosauria, that of the most distal portion, the pes, has often been neglected. In order to rectify this trend, detailed homologies of pedal muscles among sauropsids were established based on dissections and literature reviews of adult conditions. As a result, homologies of some pedal muscles between non-avian sauropsids and avians were revised, challenging classical hypotheses. The present new hypothesis postulates that the avian m. tibialis cranialis and non-avian m. extensor digitorum longus, as well as the avian m. extensor digitorum longus and non-avian m. tibialis anterior, are homologous with each other, respectively. This is more plausible because it requires no drastical change in the attachment sites between the avian and non-avian homologues unlike the classical hypothesis. Many interosseous muscles in non-archosaurian sauropsids that have long been regarded as a part of short digital extensors or flexors are also divided into multiple distinct muscles so that they can be homologized with short pedal muscles among all sauropsids. In addition, osteological correlates of attachments are identified for most of the pedal muscles, contributing to future attempts of reconstruction of this muscle system in fossil archosaurs.
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Affiliation(s)
- Soki Hattori
- Institute of Dinosaur ResearchFukui Prefectural UniversityEiheiji‐choFukuiJapan
- Fukui Prefectural Dinosaur MuseumKatsuyamaFukuiJapan
| | - Takanobu Tsuihiji
- Department of Geology and PaleontologyNational Museum of Nature and ScienceTsukubaIbarakiJapan
- Department of Earth and Planetary ScienceThe University of TokyoBunkyo‐kuTokyoJapan
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25
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Smith DK. Hind limb muscle reconstruction in the incipiently opisthopubic large therizinosaur Nothronychus (Theropoda; Maniraptora). J Anat 2021; 238:1404-1424. [PMID: 33417263 DOI: 10.1111/joa.13382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 11/23/2020] [Accepted: 11/24/2020] [Indexed: 11/30/2022] Open
Abstract
Therizinosaurs are highly modified, probably herbivorous, theropods from the Upper Cretaceous of Asia and North America. They are characterized by an extensively pneumatized axial skeleton, and in the derived forms, an incipiently opisthopubic pelvis. The evolution of such a pelvis is expected to be associated with extensive modification of the muscular system. The muscular system is reconstructed using observed muscle scars, reconstructions of the theropods Staurikosaurus and Tyrannosaurus, the ornithischian Maiasaura, and extant crocodilians and birds. The results indicate convergence with birds and ornithischian dinosaurs, such that the retroverted pubis in some maniraptorans can be regarded as analogous with the postacetabular bar in ornithischians. Functional implications also make derived therizinosaurs, such as Nothronychus, in some respects convergent with birds as the pubis is retroverted, becoming fused with the ischium, a laterally flaring synsacrum, and an avian-like pes.
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Affiliation(s)
- David K Smith
- Biology Department, Northland Pioneer College, Holbrook, AZ, USA
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26
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Schachner ER, Irmis RB, Huttenlocker AK, Sanders K, Cieri RL, Fox M, Nesbitt SJ. Osteology of the Late Triassic Bipedal Archosaur Poposaurus gracilis (Archosauria: Pseudosuchia) from Western North America. Anat Rec (Hoboken) 2020; 303:874-917. [PMID: 31814308 DOI: 10.1002/ar.24298] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 10/10/2019] [Accepted: 10/14/2019] [Indexed: 11/10/2022]
Abstract
Poposaurus gracilis is a bipedal pseudosuchian archosaur that has been poorly understood since the discovery of the holotype fragmentary partial postcranial skeleton in 1915. Poposaurus. gracilis is a member of Poposauroidea, an unusually morphologically divergent clade of pseudosuchians containing taxa that are bipedal, quadrupedal, toothed, edentulous, and some individuals with elongated thoracic neural spines (i.e., sails). In 2003, a well preserved, fully articulated, and nearly complete postcranial skeleton of P. gracilis was discovered with some fragmentary cranial elements from the Upper Triassic Chinle Formation of Grand Staircase-Escalante National Monument of southern Utah, USA. The aim of this work is to describe the osteology of this specimen in detail and compare P. gracilis to other closely related pseudosuchian archosaurs. The open neurocentral sutures throughout the majority of the vertebral column, the small size of this individual, and the presence of seven evenly spaced cyclic growth marks in the histologically sectioned femur indicate that this specimen was a skeletally immature juvenile, or subadult when it died. The pes of P. gracilis contains multiple skeletal adaptations and osteological correlates for soft tissue structures that support a hypothesis of digitigrady for this taxon. When coupled with the numerous postcranial characters associated with cursoriality, and the many anatomical traits convergent with theropod dinosaurs, this animal likely occupied a similar ecological niche with contemporaneous theropods during the Late Triassic Period. Anat Rec, 303:874-917, 2020. © 2019 American Association for Anatomy.
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Affiliation(s)
- Emma R Schachner
- Department of Cell Biology and Anatomy, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, Louisiana
| | - Randall B Irmis
- Natural History Museum of Utah, University of Utah, Salt Lake City, Utah
- Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah
| | - Adam K Huttenlocker
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Kent Sanders
- Department of Diagnostic Imaging, North Canyon Medical Center, Gooding, Idaho
| | - Robert L Cieri
- Department of Biology, University of Utah, Salt Lake City, Utah
| | - Marilyn Fox
- Department of Vertebrate Paleontology, Yale Peabody Museum, Yale University, New Haven, Connecticut
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27
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Voegele KK, Ullmann PV, Lamanna MC, Lacovara KJ. Appendicular myological reconstruction of the forelimb of the giant titanosaurian sauropod dinosaur Dreadnoughtus schrani. J Anat 2020; 237:133-154. [PMID: 32141103 DOI: 10.1111/joa.13176] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 01/06/2020] [Accepted: 01/29/2020] [Indexed: 01/08/2023] Open
Abstract
Soft tissues are variably preserved in the fossil record with external tissues, such as skin and feathers, more frequently preserved than internal tissues (e.g. muscles). More commonly, soft tissues leave traces of their locations on bones and, for muscles, these clues can be used to reconstruct the musculature of extinct vertebrates, thereby enhancing our understanding of how these organisms moved and the evolution of their locomotor patterns. Herein we reconstruct the forelimb and shoulder girdle musculature of the giant titanosaurian sauropod Dreadnoughtus schrani based on observations of osteological correlates and dissections of taxa comprising the Extant Phylogenetic Bracket of non-avian dinosaurs (crocodilians and birds). Fossils of Dreadnoughtus exhibit remarkably well-preserved, well-developed, and extensive muscle scars. Furthermore, this taxon is significantly larger-bodied than any titanosaurian for which a myological reconstruction has previously been attempted, rendering this myological study highly informative for the clade. In total, 28 muscles were investigated in this study, for which 46 osteological correlates were identified; these osteological correlates allowed the reconstruction of 16 muscles on the basis of Level I or Level II inferences (i.e. not Level I' or Level II' inferences). Comparisons with other titanosaurians suggest widespread myological variation in the clade, although potential phylogenetic patterns are often obscured by fragmentary preservation, infrequent myological studies, and lack of consensus on the systematic position of many taxa. By identifying myological variations within the clade, we can begin to address specific evolutionary and biomechanical questions related to the locomotor evolution in these sauropods.
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Affiliation(s)
| | - Paul V Ullmann
- Department of Geolgoy, Rowan University, Glassboro, NJ, USA
| | - Matthew C Lamanna
- Section of Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA, USA
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28
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Fahn-Lai P, Biewener AA, Pierce SE. Broad similarities in shoulder muscle architecture and organization across two amniotes: implications for reconstructing non-mammalian synapsids. PeerJ 2020; 8:e8556. [PMID: 32117627 PMCID: PMC7034385 DOI: 10.7717/peerj.8556] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 01/13/2020] [Indexed: 12/18/2022] Open
Abstract
The evolution of upright limb posture in mammals may have enabled modifications of the forelimb for diverse locomotor ecologies. A rich fossil record of non-mammalian synapsids holds the key to unraveling the transition from "sprawling" to "erect" limb function in the precursors to mammals, but a detailed understanding of muscle functional anatomy is a necessary prerequisite to reconstructing postural evolution in fossils. Here we characterize the gross morphology and internal architecture of muscles crossing the shoulder joint in two morphologically-conservative extant amniotes that form a phylogenetic and morpho-functional bracket for non-mammalian synapsids: the Argentine black and white tegu Salvator merianae and the Virginia opossum Didelphis virginiana. By combining traditional physical dissection of cadavers with nondestructive three-dimensional digital dissection, we find striking similarities in muscle organization and architectural parameters. Despite the wide phylogenetic gap between our study species, distal muscle attachments are notably similar, while differences in proximal muscle attachments are driven by modifications to the skeletal anatomy of the pectoral girdle that are well-documented in transitional synapsid fossils. Further, correlates for force production, physiological cross-sectional area (PCSA), muscle gearing (pennation), and working range (fascicle length) are statistically indistinguishable for an unexpected number of muscles. Functional tradeoffs between force production and working range reveal muscle specializations that may facilitate increased girdle mobility, weight support, and active stabilization of the shoulder in the opossum-a possible signal of postural transformation. Together, these results create a foundation for reconstructing the musculoskeletal anatomy of the non-mammalian synapsid pectoral girdle with greater confidence, as we demonstrate by inferring shoulder muscle PCSAs in the fossil non-mammalian cynodont Massetognathus pascuali.
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Affiliation(s)
- Philip Fahn-Lai
- Museum of Comparative Zoology, Concord Field Station and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Andrew A. Biewener
- Concord Field Station and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Stephanie E. Pierce
- Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
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29
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Piechowski R, Tałanda M. The locomotor musculature and posture of the early dinosauriform Silesaurus opolensis provides a new look into the evolution of Dinosauromorpha. J Anat 2020; 236:1044-1100. [PMID: 32003023 DOI: 10.1111/joa.13155] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 11/27/2019] [Accepted: 12/29/2019] [Indexed: 11/30/2022] Open
Abstract
It is widely accepted that ornithodirans (bird lineage) and some pseudosuchians (crocodilian lineage) achieved fully erect limb posture in different ways. Ornithodirans have buttress-erected hindlimbs, while some advanced pseudosuchians have pillar-erected hindlimbs. Analysis of the musculoskeletal apparatus of the early dinosauriform Silesaurus opolensis challenges this view. This ornithodiran had pillar-erected hindlimbs like some pseudosuchians. This condition could be autapomorphic or represents a transitional state between adductor-controlled limb posture of early dinosauromorphs and the buttress-erected hindlimbs of dinosaurs. This sequence of changes is supported by Triassic tracks left by animals of the dinosaurian lineage. It was associated with the strong development of knee flexors and extensors. Furthermore, the forelimbs of Silesaurus were fully erect, analogously to those of early sauropods. Members of both lineages reduced the muscles related to the protraction, retraction and bending of the limb. They used forelimbs more as a body support and less for propulsion. A similar scapula and humerus construction can be found in the Lagerpetidae and Lewisuchus, suggesting that long, slender, fully erected forelimbs are primitive for all Dinosauromorpha, not just Silesauridae. Early dinosaurs redeveloped several muscle attachments on the forelimb, probably in relation to bipedality.
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Affiliation(s)
- Rafał Piechowski
- Institute of Paleobiology, Polish Academy of Sciences, Warsaw, Poland.,Department of Palaeobiology and Evolution, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Warsaw, Poland
| | - Mateusz Tałanda
- Department of Palaeobiology and Evolution, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Warsaw, Poland
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30
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Zhang Y, Wang K, Chen S, Liu D, Xing H. Osteological Re‐Assessment and Taxonomic Revision of
“Tanius laiyangensis”
(Ornithischia: Hadrosauroidea) from the Upper Cretaceous of Shandong, China. Anat Rec (Hoboken) 2019; 303:790-800. [DOI: 10.1002/ar.24097] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 10/07/2018] [Accepted: 10/26/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Yu‐Guang Zhang
- Beijing Museum of Natural HistoryBeijing Academy of Science and Technology Beijing People's Republic of China
| | - Ke‐Bai Wang
- Zhucheng Dinosaur MuseumDinosaur Research Center of Zhucheng Zhucheng Shandong People's Republic of China
| | - Shu‐Qing Chen
- Zhucheng Dinosaur MuseumDinosaur Research Center of Zhucheng Zhucheng Shandong People's Republic of China
| | - Di Liu
- Beijing Museum of Natural HistoryBeijing Academy of Science and Technology Beijing People's Republic of China
| | - Hai Xing
- Beijing Museum of Natural HistoryBeijing Academy of Science and Technology Beijing People's Republic of China
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31
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Molnar JL, Diogo R, Hutchinson JR, Pierce SE. Evolution of Hindlimb Muscle Anatomy Across the Tetrapod Water‐to‐Land Transition, Including Comparisons With Forelimb Anatomy. Anat Rec (Hoboken) 2018; 303:218-234. [DOI: 10.1002/ar.23997] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 03/07/2018] [Accepted: 03/15/2018] [Indexed: 12/19/2022]
Affiliation(s)
- Julia L. Molnar
- Department of AnatomyNew York Institute of Technology College of Osteopathic Medicine Northern Boulevard, Old Westbury New York
| | - Rui Diogo
- Department of AnatomyHoward University College of Medicine, 520 W St. NW, Numa Adams Building Washington District of Columbia
| | - John R. Hutchinson
- Department of Comparative Biomedical Sciences, Royal Veterinary CollegeStructure and Motion Lab Hawkshead Lane, Hatfield, Hertfordshire, AL9 7TA UK
| | - Stephanie E. Pierce
- Museum of Comparative Zoology and Department of Organismic and Evolutionary BiologyHarvard University, 26 Oxford Street Cambridge Massachusetts
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32
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Klinkhamer AJ, Mallison H, Poropat SF, Sloan T, Wroe S. Comparative Three‐Dimensional Moment Arm Analysis of the Sauropod Forelimb: Implications for the Transition to a Wide‐Gauge Stance in Titanosaurs. Anat Rec (Hoboken) 2018; 302:794-817. [DOI: 10.1002/ar.23977] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 06/28/2018] [Accepted: 08/15/2018] [Indexed: 01/22/2023]
Affiliation(s)
- Ada J. Klinkhamer
- Function, Evolution and Anatomy Research Laboratory School of Environmental and Rural Science, University of New England Armidale New South Wales Australia
- Australian Age of Dinosaurs Museum of Natural History Winton Queensland Australia
| | | | - Stephen F. Poropat
- Australian Age of Dinosaurs Museum of Natural History Winton Queensland Australia
- Department of Chemistry and Biotechnology Swinburne University of Technology Hawthorn Victoria Australia
| | - Trish Sloan
- Australian Age of Dinosaurs Museum of Natural History Winton Queensland Australia
| | - Stephen Wroe
- Function, Evolution and Anatomy Research Laboratory School of Environmental and Rural Science, University of New England Armidale New South Wales Australia
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33
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Klinkhamer AJ, Mallison H, Poropat SF, Sinapius GH, Wroe S. Three‐Dimensional Musculoskeletal Modeling of the Sauropodomorph Hind Limb: The Effect of Postural Change on Muscle Leverage. Anat Rec (Hoboken) 2018; 301:2145-2163. [DOI: 10.1002/ar.23950] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 05/14/2018] [Accepted: 06/01/2018] [Indexed: 12/27/2022]
Affiliation(s)
- Ada J. Klinkhamer
- Function, Evolution, and Anatomy Research Lab, School of Environmental and Rural Science University of New England Armidale New South Wales Australia
- Australian Age of Dinosaurs Museum of Natural History Winton Queenland Australia
| | | | - Stephen F. Poropat
- Australian Age of Dinosaurs Museum of Natural History Winton Queenland Australia
- Faculty of Science, Engineering, and Technology Swinburne University of Technology Hawthorn Victoria Australia
| | - George H.K. Sinapius
- Australian Age of Dinosaurs Museum of Natural History Winton Queenland Australia
| | - Stephen Wroe
- Function, Evolution, and Anatomy Research Lab, School of Environmental and Rural Science University of New England Armidale New South Wales Australia
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34
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Prieto-Marquez A, Guenther MF. Perinatal specimens of Maiasaura from the Upper Cretaceous of Montana (USA): insights into the early ontogeny of saurolophine hadrosaurid dinosaurs. PeerJ 2018; 6:e4734. [PMID: 29785343 PMCID: PMC5960587 DOI: 10.7717/peerj.4734] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 04/18/2018] [Indexed: 11/20/2022] Open
Abstract
Perinatal specimens of hadrosaurids discovered in the late 1970’s by field crews from Princeton University were significant in providing evidence of the early ontogenetic stages in North American dinosaurs. These specimens from the Campanian (Upper Cretaceous) Two Medicine Formation of Montana consist of over a dozen skeletons referable to the saurolophine hadrosaurid Maiasaura peeblesorum, but never fully figured or described. Here, we provide a more complete documentation of the morphology of these specimens, along with an examination of variation during a large span of the development of saurolophine hadrosaurids. Many ontogenetic changes in the available facial and mandibular elements are associated with the progressive elongation of the preorbital region of the skull and mandible. In the postcranium, limb bones change nearly isometrically, with exception of certain elements of the forelimb. Some cranial and postcranial characters commonly used for inferring hadrosaurid phylogenetic relationships remain invariable during the ontogeny of M. peeblesorum. This indicates that early ontogenetic stages may still provide a limited amount of character information useful for systematics and phylogenetic inference.
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Affiliation(s)
- Albert Prieto-Marquez
- Mesozoic Research, Catalan Institute of Paleontology Miquel Crusafont, Sabadell, Spain
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35
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Abstract
Understanding ontogenetic patterns is important in vertebrate paleontology because the assessed skeletal maturity of an individual often has implications for paleobiogeography, species synonymy, paleobiology, and body size evolution of major clades. Further, for many groups the only means of confidently determining ontogenetic status of an organism is through the destructive process of histological sampling. Although the ontogenetic patterns of Late Jurassic and Cretaceous dinosaurs are better understood, knowledge of the ontogeny of the earliest dinosaurs is relatively poor because most species-level growth series known from these groups are small (usually, maximum of n ~ 5) and incomplete. To investigate the morphological changes that occur during ontogeny in early dinosaurs, I used ontogenetic sequence analysis (OSA) to reconstruct developmental sequences of morphological changes in the postcranial ontogeny of the early theropods Coelophysis bauri and Megapnosaurus rhodesiensis, both of which are known from large sample sizes (n = 174 and 182, respectively). I found a large amount of sequence polymorphism (i.e. intraspecific variation in developmental patterns) in both taxa, and especially in C. bauri, which possesses this variation in every element analyzed. Megapnosaurus rhodesiensis is similar, but it possesses no variation in the sequence of development of ontogenetic characters in the tibia and tarsus. Despite the large amount of variation in development, many characters occur consistently earlier or later in ontogeny and could therefore be important morphological features for assessing the relative maturity of other early theropods. Additionally, there is a phylogenetic signal to the order in which homologous characters appear in ontogeny, with homologous characters appearing earlier or later in developmental sequences of early theropods and the close relatives of dinosaurs, silesaurids. Many of these morphological features are important characters for the reconstruction of archosaurian phylogeny (e.g. trochanteric shelf). Because these features vary in presence or appearance with ontogeny, these characters should be used with caution when undertaking phylogenetic analyses in these groups, since a specimen may possess certain character states owing to ontogenetic stage, not evolutionary relationships.
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Affiliation(s)
- C. T. Griffin
- Department of GeosciencesVirginia TechBlacksburgVAUSA
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36
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Molnar JL, Diogo R, Hutchinson JR, Pierce SE. Reconstructing pectoral appendicular muscle anatomy in fossil fish and tetrapods over the fins-to-limbs transition. Biol Rev Camb Philos Soc 2017; 93:1077-1107. [DOI: 10.1111/brv.12386] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Revised: 10/02/2017] [Accepted: 10/13/2017] [Indexed: 12/16/2022]
Affiliation(s)
- Julia L. Molnar
- Department of Anatomy; New York Institute of Technology College of Osteopathic Medicine, Northern Boulevard; Old Westbury NY U.S.A
| | - Rui Diogo
- Department of Anatomy; Howard University College of Medicine, 520 W St. NW, Numa Adams Building; Washington DC 20059 U.S.A
| | - John R. Hutchinson
- Structure and Motion Lab; Royal Veterinary College, Hawkshead Lane, Hatfield; Hertfordshire AL9 7TA UK
| | - Stephanie E. Pierce
- Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology; Harvard University, 26 Oxford Street; Cambridge MA 02138 U.S.A
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Brusatte SL, Dumbravă M, Vremir M, Csiki-Sava Z, Totoianu R, Norell MA. A Catalog ofZalmoxes(Dinosauria: Ornithopoda) Specimens from the Upper Cretaceous Nălaţ-Vad Locality, Haţeg Basin, Romania. AMERICAN MUSEUM NOVITATES 2017. [DOI: 10.1206/3884.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
| | - Mihai Dumbravă
- Faculty of Biology and Geology, Babeş-Bolyai University, Cluj-Napoca, Romania
| | - Mátyás Vremir
- Department of Natural Sciences, Transylvanian Museum Society, Cluj-Napoca, Romania
| | - Zoltán Csiki-Sava
- Laboratory of Paleontology, University of Bucharest, Bucharest, Romania
| | - Radu Totoianu
- “Ioan Raica” Municipal Museum of Sebeş, Sebeş, Romania
| | - Mark A. Norell
- Division of Paleontology, American Museum of Natural History, New York
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38
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Molnar JL, Diaz RE, Skorka T, Dagliyan G, Diogo R. Comparative musculoskeletal anatomy of chameleon limbs, with implications for the evolution of arboreal locomotion in lizards and for teratology. J Morphol 2017; 278:1241-1261. [DOI: 10.1002/jmor.20708] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 04/10/2017] [Accepted: 05/01/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Julia L. Molnar
- Department of Anatomy; Howard University College of Medicine; 520 W Street NW Washington DC 20059
| | - Raul E. Diaz
- Department of Biology; La Sierra University; 4500 Riverwalk Parkway Riverside California 92505
| | - Tautis Skorka
- Keck School of Medicine, Molecular Imaging Center, University of Southern California; 2250 Alcazar Street Los Angeles California 90033
| | - Grant Dagliyan
- Keck School of Medicine, Molecular Imaging Center, University of Southern California; 2250 Alcazar Street Los Angeles California 90033
| | - Rui Diogo
- Department of Anatomy; Howard University College of Medicine; 520 W Street NW Washington DC 20059
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Ullmann PV, Bonnan MF, Lacovara KJ. Characterizing the Evolution of Wide-Gauge Features in Stylopodial Limb Elements of Titanosauriform Sauropods via Geometric Morphometrics. Anat Rec (Hoboken) 2017; 300:1618-1635. [DOI: 10.1002/ar.23607] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 09/08/2016] [Accepted: 01/11/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Paul V. Ullmann
- Department of Geology; Rowan University; Glassboro New Jersey
| | - Matthew F. Bonnan
- Biology Program, School of Natural Sciences & Mathematics; Stockton University; Galloway New Jersey
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Digital dissection and three-dimensional interactive models of limb musculature in the Australian estuarine crocodile (Crocodylus porosus). PLoS One 2017; 12:e0175079. [PMID: 28384201 PMCID: PMC5383063 DOI: 10.1371/journal.pone.0175079] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 03/20/2017] [Indexed: 01/07/2023] Open
Abstract
Digital dissection is a relatively new technique that has enabled scientists to gain a better understanding of vertebrate anatomy. It can be used to rapidly disseminate detailed, three-dimensional information in an easily accessible manner that reduces the need for destructive, traditional dissections. Here we present the results of a digital dissection on the appendicular musculature of the Australian estuarine crocodile (Crocodylus porosus). A better understanding of this until now poorly known system in C. porosus is important, not only because it will expand research into crocodilian locomotion, but because of its potential to inform muscle reconstructions in dinosaur taxa. Muscles of the forelimb and hindlimb are described and three-dimensional interactive models are included based on CT and MRI scans as well as fresh-tissue dissections. Differences in the arrangement of musculature between C. porosus and other groups within the Crocodylia were found. In the forelimb, differences are restricted to a single tendon of origin for triceps longus medialis. For the hindlimb, a reduction in the number of heads of ambiens was noted as well as changes to the location of origin and insertion for iliofibularis and gastrocnemius externus.
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Dieudonné PE, Tortosa T, Torcida Fernández-Baldor F, Canudo JI, Díaz-Martínez I. An Unexpected Early Rhabdodontid from Europe (Lower Cretaceous of Salas de los Infantes, Burgos Province, Spain) and a Re-Examination of Basal Iguanodontian Relationships. PLoS One 2016; 11:e0156251. [PMID: 27333279 PMCID: PMC4917257 DOI: 10.1371/journal.pone.0156251] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Accepted: 05/11/2016] [Indexed: 11/30/2022] Open
Abstract
Disarticulated and incomplete remains from a new diminutive ornithopod are described. They come from the Cameros Basin in the north of Spain and were collected from the red clays of the Castrillo de la Reina Formation, ranging from Upper Barremian to Lower Aptian. The new ornithopod described here is slender and one of the smallest ever reported. An up-to-date phylogenetic analysis recovers this taxon as a basal iguanodontian. Its unique combination of characters makes it more derived than slender ornithopods like Hyphilophodon and Gasparinisaura, and bring very interesting insights into the basal iguanodontian phylogeny. Though possessing a minimum of three premaxillary teeth, this taxon also bears an extensor ilio-tibialis groove on the distal part of its femur. Moreover, its dentary and maxillary teeth are unique, remarkably similar to those regarded as having a "rhabdomorphan" affinity. This unknown taxon is suggested to be a stem taxon within Rhabdodontidae, a successful clade of basal iguanodonts from the Late Cretaceous of Europe. The Gondwanan ornithopods share the strongest affinities with this family, and we confirm Muttaburrasaurus as a sister taxon of the Rhabdodontidae within a newly defined clade, the Rhabdodontomorpha.
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Affiliation(s)
- Paul-Emile Dieudonné
- Grupo Aragosaurus−IUCA, Área de Paleontología, Facultad de Ciencias, Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Thierry Tortosa
- Réserve Naturelle Nationale Sainte-Victoire, Conseil Départemental des Bouches-du-Rhône, 52 avenue de Saint-Just, 13256 Marseille Cedex 20, France
| | - Fidel Torcida Fernández-Baldor
- Museo de Dinosaurios de Salas de los Infantes and Colectivo Arqueológico−Paleontológico Salense (CAS), Plaza Jesús Aparicio 9, 09600 Salas de los Infantes, Burgos, Spain
| | - José Ignacio Canudo
- Grupo Aragosaurus−IUCA, Área de Paleontología, Facultad de Ciencias, Universidad de Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain
| | - Ignacio Díaz-Martínez
- CONICET—Instituto de Investigación en Paleobiología y Geología, Universidad Nacional de Río Negro, General Roca 1242, 8332 Fisque Menuco (General Roca), Río Negro, Argentina
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Lima FC, Leite AV, Santos ALQ, Sabec-Pereira DK, Araújo EG, Pereira KF. MUSCULAR ANATOMY OF THE PECTORAL AND FORELIMB OF Caiman crocodilus crocodilus (LINNAEUS, 1758) (CROCODYLIA: ALLIGATORIDAE). CIÊNCIA ANIMAL BRASILEIRA 2016. [DOI: 10.1590/1089-6891v17i233788] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Abstract Among the Brazilian crocodilian, Caiman crocodilus crocodilus is widely distributed, given its adaptation to diverse habitats and their generalist diet. Information about the reproductive and ethological character of this species is abundant, whereas morphological data are still scarce. This study aimed to identify and report the muscles and their origin and the insertion into the pectoral and forelimb of C. crocodilus crocodilus. We used two male specimens, adults, belonging to the collection of the UFG - Jataí. We performed usual procedures for dissection and further individualization, withdrawal of members, and observation of muscle origins and insertions. The musculature of C. crocodilus crocodilus generally conservative is similar to C. latirostris and A. mississippiensis. The muscles of the pectoral girdle showed little variation among crocodilians. In the forelimb, the triceps muscle has five distinct heads and biceps has only one. The extensor and flexor surface of the hand showed similar topography to A. mississippiensis. We described some differences in the origin and insertion of certain muscles, as well as the classification and topography of some flexor and extensor muscles in the forearm segment. The distal segments showed more variations, which probably reflects the variety of locomotor habits among crocodilians.
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Nesbitt SJ, Flynn JJ, Pritchard AC, Parrish JM, Ranivoharimanana L, Wyss AR. Postcranial Osteology ofAzendohsaurus madagaskarensis(?Middle to Upper Triassic, Isalo Group, Madagascar) and its Systematic Position Among Stem Archosaur Reptiles. BULLETIN OF THE AMERICAN MUSEUM OF NATURAL HISTORY 2015. [DOI: 10.1206/amnb-899-00-1-126.1] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Freedman Fowler EA, Horner JR. A New Brachylophosaurin Hadrosaur (Dinosauria: Ornithischia) with an Intermediate Nasal Crest from the Campanian Judith River Formation of Northcentral Montana. PLoS One 2015; 10:e0141304. [PMID: 26560175 PMCID: PMC4641681 DOI: 10.1371/journal.pone.0141304] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 10/07/2015] [Indexed: 11/18/2022] Open
Abstract
Background Brachylophosaurini is a clade of hadrosaurine dinosaurs currently known from the Campanian (Late Cretaceous) of North America. Its members include: Acristavus gagslarsoni, which lacks a nasal crest; Brachylophosaurus canadensis, which possesses a flat paddle-shaped nasal crest projecting posteriorly over the dorsal skull roof; and Maiasaura peeblesorum, which possesses a dorsally-projecting nasofrontal crest. Acristavus, from the lower Two Medicine Formation of Montana (~81–80 Ma), is hypothesized to be the ancestral member of the clade. Brachylophosaurus specimens are from the middle Oldman Formation of Alberta and equivalent beds in the Judith River Formation of Montana; the upper Oldman Formation is dated 77.8 Ma. Methodology/Principal Findings A new brachylophosaurin hadrosaur, Probrachylophosaurus bergei (gen. et sp. nov.) is described and phylogenetically analyzed based on the skull and postcranium of a large individual from the Judith River Formation of northcentral Montana (79.8–79.5 Ma); the horizon is equivalent to the lower Oldman Formation of Alberta. Cranial morphology of Probrachylophosaurus, most notably the nasal crest, is intermediate between Acristavus and Brachylophosaurus. In Brachylophosaurus, the nasal crest lengthens and flattens ontogenetically, covering the supratemporal fenestrae in large adults. The smaller nasal crest of Probrachylophosaurus is strongly triangular in cross section and only minimally overhangs the supratemporal fenestrae, similar to an ontogenetically earlier stage of Brachylophosaurus. Sutural fusion and tibial osteohistology reveal that the holotype of Probrachylophosaurus was relatively more mature than a similarly large Brachylophosaurus specimen; thus, Probrachylophosaurus is not simply an immature Brachylophosaurus. Conclusions/Significance The small triangular posteriorly oriented nasal crest of Probrachylophosaurus is proposed to represent a transitional nasal morphology between that of a non-crested ancestor such as Acristavus and the large flat posteriorly oriented nasal crest of adult Brachylophosaurus. Because Probrachylophosaurus is stratigraphically and morphologically intermediate between these taxa, Probrachylophosaurus is hypothesized to be an intermediate member of the Acristavus-Brachylophosaurus evolutionary lineage.
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Affiliation(s)
- Elizabeth A. Freedman Fowler
- Museum of the Rockies, Montana State University, Bozeman, Montana, United States of America
- Department of Earth Sciences, Montana State University, Bozeman, Montana, United States of America
- * E-mail:
| | - John R. Horner
- Museum of the Rockies, Montana State University, Bozeman, Montana, United States of America
- Department of Earth Sciences, Montana State University, Bozeman, Montana, United States of America
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Figueiredo SI, Araújo LB, Ferraz RH, Guimarães FR, Cantarini JL, Araújo EG. Bases ósseas e musculares dos cortes comerciais do tronco de jacaré-do-Pantanal (Caimanyacare Daudin, 1802). PESQUISA VETERINARIA BRASILEIRA 2015. [DOI: 10.1590/s0100-736x2015000800007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Resumo: O consumo de carne de jacaré-do-Pantanal tornou-se uma tendência de mercado e uma cadeia produtiva em ascensão no Estado de Mato Grosso, sendo 28,40% da carne comercializada nos últimos quatro anos oriundos do tronco. Estudos evolutivos, morfofisiológicos, ontogenéticos e tecnológicos foram desenvolvidos, mas não há descrição da musculatura e bases ósseas dos cortes comerciais. Objetivou-se descrever os músculos e correspondentes bases ósseas dos cortes filé de lombo, filé mignon e aparas. Na descrição óssea, utilizaram-se seis carcaças desossadas de exemplares juvenis de jacaré-do-Pantanal, além de um exemplar adulto, obtido por doação após óbito, do Zoológico da UFMT. Os ossos foram macerados em água corrente, clareados e descritos. Para a descrição muscular, 24 exemplares juvenis foram abatidos e esfolados, conservados em freezer e descongelados quando utilizados, sem qualquer fixação. Após a evisceração, foram dissecados em ambos os antímeros. Os músculos semiespinhal, longuíssimo e iliocostal, fixados nas vértebras e costelas torácicas, lombares e sacrais, formam o filé de lombo. O corte aparas é constituído pelos músculos grande dorsal, serrátil, peitoral e abdominais (oblíquo externo, oblíquo interno, transverso e reto), cuja base óssea corresponde as costelas torácicas, lombares e sacrais, a gastrália, o esterno e o epipúbis. Por sua vez, o m. puboisquiofemoral interno cranial, localizado na região sublombar e o m. troncocaudal, da superfície ventral da pelve, compreendem o filé mignon.
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Francisco Botelho J, Smith-Paredes D, Soto-Acuña S, Mpodozis J, Palma V, Vargas AO. Skeletal plasticity in response to embryonic muscular activity underlies the development and evolution of the perching digit of birds. Sci Rep 2015; 5:9840. [PMID: 25974685 PMCID: PMC4431314 DOI: 10.1038/srep09840] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 03/11/2015] [Indexed: 01/17/2023] Open
Abstract
Most birds have an opposable digit 1 (hallux) allowing the foot to grasp, which evolved from the non-opposable hallux of early theropod dinosaurs. An important morphological difference with early theropods is the twisting of the long axis of its metatarsal. Here, we show how embryonic musculature and the onset of its activity are required for twisting of metatarsal 1 (Mt1) and retroversion of the hallux. Pharmacologically paralyzed embryos do not fully retrovert the hallux and have a straight Mt1 shaft, phenocopying the morphology of early tetanuran dinosaurs. Molecular markers of cartilage maturation and ossification show that differentiation of Mt1 is significantly delayed compared to Mt2-4. We hypothesize on how delayed maturation may have increased plasticity, facilitating muscular twisting. Our experimental results emphasize the importance of embryonic muscular activity in the evolutionary origin of a crucial adaptation.
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Affiliation(s)
- João Francisco Botelho
- Departamento de Biología, Facultad de Ciencias de la Universidad de Chile and FONDAP Center for Genome Regulation. Las Palmeras 3425, Santiago, Chile. 7800003
| | - Daniel Smith-Paredes
- Departamento de Biología, Facultad de Ciencias de la Universidad de Chile and FONDAP Center for Genome Regulation. Las Palmeras 3425, Santiago, Chile. 7800003
| | - Sergio Soto-Acuña
- Departamento de Biología, Facultad de Ciencias de la Universidad de Chile and FONDAP Center for Genome Regulation. Las Palmeras 3425, Santiago, Chile. 7800003
| | - Jorge Mpodozis
- Departamento de Biología, Facultad de Ciencias de la Universidad de Chile and FONDAP Center for Genome Regulation. Las Palmeras 3425, Santiago, Chile. 7800003
| | - Verónica Palma
- Departamento de Biología, Facultad de Ciencias de la Universidad de Chile and FONDAP Center for Genome Regulation. Las Palmeras 3425, Santiago, Chile. 7800003
| | - Alexander O Vargas
- Departamento de Biología, Facultad de Ciencias de la Universidad de Chile and FONDAP Center for Genome Regulation. Las Palmeras 3425, Santiago, Chile. 7800003
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Botelho JF, Ossa-Fuentes L, Soto-Acuña S, Smith-Paredes D, Nuñez-León D, Salinas-Saavedra M, Ruiz-Flores M, Vargas AO. New developmental evidence clarifies the evolution of wrist bones in the dinosaur-bird transition. PLoS Biol 2014; 12:e1001957. [PMID: 25268520 PMCID: PMC4181957 DOI: 10.1371/journal.pbio.1001957] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 08/20/2014] [Indexed: 01/22/2023] Open
Abstract
From early dinosaurs with as many as nine wrist bones, modern birds evolved to develop only four ossifications. Their identity is uncertain, with different labels used in palaeontology and developmental biology. We examined embryos of several species and studied chicken embryos in detail through a new technique allowing whole-mount immunofluorescence of the embryonic cartilaginous skeleton. Beyond previous controversy, we establish that the proximal-anterior ossification develops from a composite radiale+intermedium cartilage, consistent with fusion of radiale and intermedium observed in some theropod dinosaurs. Despite previous claims that the development of the distal-anterior ossification does not support the dinosaur-bird link, we found its embryonic precursor shows two distinct regions of both collagen type II and collagen type IX expression, resembling the composite semilunate bone of bird-like dinosaurs (distal carpal 1+distal carpal 2). The distal-posterior ossification develops from a cartilage referred to as "element x," but its position corresponds to distal carpal 3. The proximal-posterior ossification is perhaps most controversial: It is labelled as the ulnare in palaeontology, but we confirm the embryonic ulnare is lost during development. Re-examination of the fossil evidence reveals the ulnare was actually absent in bird-like dinosaurs. We confirm the proximal-posterior bone is a pisiform in terms of embryonic position and its development as a sesamoid associated to a tendon. However, the pisiform is absent in bird-like dinosaurs, which are known from several articulated specimens. The combined data provide compelling evidence of a remarkable evolutionary reversal: A large, ossified pisiform re-evolved in the lineage leading to birds, after a period in which it was either absent, nonossified, or very small, consistently escaping fossil preservation. The bird wrist provides a modern example of how developmental and paleontological data illuminate each other. Based on all available data, we introduce a new nomenclature for bird wrist ossifications.
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Affiliation(s)
- João Francisco Botelho
- Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Luis Ossa-Fuentes
- Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Sergio Soto-Acuña
- Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Daniel Smith-Paredes
- Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Daniel Nuñez-León
- Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Miguel Salinas-Saavedra
- Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Macarena Ruiz-Flores
- Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Alexander O. Vargas
- Laboratorio de Ontogenia y Filogenia, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
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Burch SH. Complete forelimb myology of the basal theropod dinosaur Tawa hallae based on a novel robust muscle reconstruction method. J Anat 2014; 225:271-97. [PMID: 25040486 DOI: 10.1111/joa.12216] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/07/2014] [Indexed: 11/28/2022] Open
Abstract
The forelimbs of nonavian theropod dinosaurs have been the subject of considerable study and speculation due to their varied morphology and role in the evolution of flight. Although many studies on the functional morphology of a limb require an understanding of its musculature, comparatively little is known about the forelimb myology of theropods and other bipedal dinosaurs. Previous phylogenetically based myological reconstructions have been limited to the shoulder, restricting their utility in analyses of whole-limb function. The antebrachial and manual musculature in particular have remained largely unstudied due to uncertain muscular homologies in archosaurs. Through analysis of the musculature of extant taxa in a robust statistical framework, this study presents new hypotheses of homology for the distal limb musculature of archosaurs and provides the first complete reconstruction of dinosaurian forelimb musculature, including the antebrachial and intrinsic manual muscles. Data on the forelimb myology of a broad sample of extant birds, crocodylians, lizards, and turtles were analyzed using maximum likelihood ancestral state reconstruction and examined together with the osteology of the early theropod Tawa hallae from the Late Triassic of New Mexico to formulate a complete plesiomorphic myology for the theropod forelimb. Comparisons with previous reconstructions show that the shoulder musculature of basal theropods is more similar to that of basal ornithischians and sauropodomorphs than to that of dromaeosaurids. Greater development of the supracoracoideus and deltoideus musculature in theropods over other bipedal dinosaurs correlates with stronger movements of the forelimb at the shoulder and an emphasis on apprehension of relatively large prey. This emphasis is further supported by the morphology of the antebrachium and the intrinsic manual musculature, which exhibit a high degree of excursion and a robust morphology well-suited for powerful digital flexion. The forelimb myology of Tawa established here helps infer the ancestral conformation of the forelimb musculature and the osteological correlates of major muscle groups in early theropods. These data are critical for investigations addressing questions relating to the evolution of specialized forelimb function across Theropoda.
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Affiliation(s)
- Sara H Burch
- Department of Biomedical Sciences, Ohio University, Athens, OH, USA
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Diogo R, Molnar J. Comparative Anatomy, Evolution, and Homologies of Tetrapod Hindlimb Muscles, Comparison with Forelimb Muscles, and Deconstruction of the Forelimb-Hindlimb Serial Homology Hypothesis. Anat Rec (Hoboken) 2014; 297:1047-75. [DOI: 10.1002/ar.22919] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2013] [Revised: 02/17/2014] [Accepted: 02/28/2014] [Indexed: 01/02/2023]
Affiliation(s)
- Rui Diogo
- Anatomy Department; Howard University College of Medicine; Washington DC 20059
| | - Julia Molnar
- Anatomy Department; Howard University College of Medicine; Washington DC 20059
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McPhee BW, Yates AM, Choiniere JN, Abdala F. The complete anatomy and phylogenetic relationships ofAntetonitrus ingenipes(Sauropodiformes, Dinosauria): implications for the origins of Sauropoda. Zool J Linn Soc 2014. [DOI: 10.1111/zoj.12127] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Blair W. McPhee
- Evolutionary Studies Institute; Centre of Excellence in Palaeosciences; University of the Witwatersrand; Private Bag 3 Johannesburg Gauteng 2050 South Africa
- NRF/DST Centre of Excellence in Palaeosciences; University of the Witwatersrand; Private Bag 3 Johannesburg Gauteng 2050 South Africa
| | - Adam M. Yates
- Museum of Central Australia; Araluen Cultural Precinct; P.O. Box 3521 Alice Springs Northern Territory 0871 Australia
| | - Jonah N. Choiniere
- Evolutionary Studies Institute; Centre of Excellence in Palaeosciences; University of the Witwatersrand; Private Bag 3 Johannesburg Gauteng 2050 South Africa
- NRF/DST Centre of Excellence in Palaeosciences; University of the Witwatersrand; Private Bag 3 Johannesburg Gauteng 2050 South Africa
| | - Fernando Abdala
- Evolutionary Studies Institute; Centre of Excellence in Palaeosciences; University of the Witwatersrand; Private Bag 3 Johannesburg Gauteng 2050 South Africa
- NRF/DST Centre of Excellence in Palaeosciences; University of the Witwatersrand; Private Bag 3 Johannesburg Gauteng 2050 South Africa
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