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Yu D, Ren Y, Uesaka M, Beavan AJS, Muffato M, Shen J, Li Y, Sato I, Wan W, Clark JW, Keating JN, Carlisle EM, Dearden RP, Giles S, Randle E, Sansom RS, Feuda R, Fleming JF, Sugahara F, Cummins C, Patricio M, Akanni W, D'Aniello S, Bertolucci C, Irie N, Alev C, Sheng G, de Mendoza A, Maeso I, Irimia M, Fromm B, Peterson KJ, Das S, Hirano M, Rast JP, Cooper MD, Paps J, Pisani D, Kuratani S, Martin FJ, Wang W, Donoghue PCJ, Zhang YE, Pascual-Anaya J. Hagfish genome elucidates vertebrate whole-genome duplication events and their evolutionary consequences. Nat Ecol Evol 2024; 8:519-535. [PMID: 38216617 DOI: 10.1038/s41559-023-02299-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 12/04/2023] [Indexed: 01/14/2024]
Abstract
Polyploidy or whole-genome duplication (WGD) is a major event that drastically reshapes genome architecture and is often assumed to be causally associated with organismal innovations and radiations. The 2R hypothesis suggests that two WGD events (1R and 2R) occurred during early vertebrate evolution. However, the timing of the 2R event relative to the divergence of gnathostomes (jawed vertebrates) and cyclostomes (jawless hagfishes and lampreys) is unresolved and whether these WGD events underlie vertebrate phenotypic diversification remains elusive. Here we present the genome of the inshore hagfish, Eptatretus burgeri. Through comparative analysis with lamprey and gnathostome genomes, we reconstruct the early events in cyclostome genome evolution, leveraging insights into the ancestral vertebrate genome. Genome-wide synteny and phylogenetic analyses support a scenario in which 1R occurred in the vertebrate stem-lineage during the early Cambrian, and 2R occurred in the gnathostome stem-lineage, maximally in the late Cambrian-earliest Ordovician, after its divergence from cyclostomes. We find that the genome of stem-cyclostomes experienced an additional independent genome triplication. Functional genomic and morphospace analyses demonstrate that WGD events generally contribute to developmental evolution with similar changes in the regulatory genome of both vertebrate groups. However, appreciable morphological diversification occurred only in the gnathostome but not in the cyclostome lineage, calling into question the general expectation that WGDs lead to leaps of bodyplan complexity.
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Affiliation(s)
- Daqi Yu
- Key Laboratory of Zoological Systematics and Evolution and State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yandong Ren
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, China
| | - Masahiro Uesaka
- Laboratory for Evolutionary Morphology, RIKEN Center for Biosystems Dynamics Research (BDR), Kobe, Japan
- Department of Ecological Developmental Adaptability Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Alan J S Beavan
- Bristol Palaeobiology Group, School of Biological Sciences, University of Bristol, Bristol, UK
- School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Matthieu Muffato
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, UK
- Tree of Life, Wellcome Sanger Institute, Hinxton, UK
| | - Jieyu Shen
- Key Laboratory of Zoological Systematics and Evolution and State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yongxin Li
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, China
| | - Iori Sato
- Laboratory for Evolutionary Morphology, RIKEN Center for Biosystems Dynamics Research (BDR), Kobe, Japan
- iPS Cell Advanced Characterization and Development Team, RIKEN BioResource Research Center, Tsukuba, Japan
| | - Wenting Wan
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, China
| | - James W Clark
- Bristol Palaeobiology Group, School of Biological Sciences, University of Bristol, Bristol, UK
- Milner Centre for Evolution, University of Bath, Claverton Down, Bath, UK
| | - Joseph N Keating
- Bristol Palaeobiology Group, School of Earth Sciences, University of Bristol, Bristol, UK
| | - Emily M Carlisle
- Bristol Palaeobiology Group, School of Earth Sciences, University of Bristol, Bristol, UK
| | - Richard P Dearden
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK
- Naturalis Biodiversity Center, Leiden, the Netherlands
| | - Sam Giles
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Emma Randle
- Department of Earth and Environmental Sciences, University of Manchester, Manchester, UK
| | - Robert S Sansom
- Department of Earth and Environmental Sciences, University of Manchester, Manchester, UK
| | - Roberto Feuda
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - James F Fleming
- Keio University Institute for Advanced Biosciences, Tsuruoka, Japan
- Natural History Museum, University of Oslo, Oslo, Norway
| | - Fumiaki Sugahara
- Division of Biology, Hyogo Medical University, Nishinomiya, Japan
- Evolutionary Morphology Laboratory, RIKEN Cluster for Pioneering Research (CPR), Kobe, Japan
| | - Carla Cummins
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, UK
| | - Mateus Patricio
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, UK
| | - Wasiu Akanni
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, UK
| | - Salvatore D'Aniello
- Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn Napoli, Villa Comunale, Napoli, Italy
| | - Cristiano Bertolucci
- Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn Napoli, Villa Comunale, Napoli, Italy
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Naoki Irie
- Research Center for Integrative Evolutionary Science, The Graduate University for Advanced Studies, SOKENDAI, Hayama, Japan
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Cantas Alev
- Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto, Japan
| | - Guojun Sheng
- International Research Center for Medical Sciences (IRCMS), Kumamoto University, Kumamoto, Japan
| | - Alex de Mendoza
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK
| | - Ignacio Maeso
- Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona (UB), Barcelona, Spain
- Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona (UB), Barcelona, Spain
| | - Manuel Irimia
- Centre for Genomic Regulation (CRG), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- ICREA, Barcelona, Spain
| | - Bastian Fromm
- The Arctic University Museum of Norway, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Kevin J Peterson
- Department of Biological Sciences, Dartmouth College, Hanover, NH, USA
| | - Sabyasachi Das
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, USA
- Emory Vaccine Center, Emory University, Atlanta, GA, USA
| | - Masayuki Hirano
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, USA
- Emory Vaccine Center, Emory University, Atlanta, GA, USA
| | - Jonathan P Rast
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, USA
- Emory Vaccine Center, Emory University, Atlanta, GA, USA
| | - Max D Cooper
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, USA
- Emory Vaccine Center, Emory University, Atlanta, GA, USA
| | - Jordi Paps
- Bristol Palaeobiology Group, School of Earth Sciences, University of Bristol, Bristol, UK
| | - Davide Pisani
- Bristol Palaeobiology Group, School of Biological Sciences, University of Bristol, Bristol, UK
- Bristol Palaeobiology Group, School of Earth Sciences, University of Bristol, Bristol, UK
| | - Shigeru Kuratani
- Laboratory for Evolutionary Morphology, RIKEN Center for Biosystems Dynamics Research (BDR), Kobe, Japan
- Evolutionary Morphology Laboratory, RIKEN Cluster for Pioneering Research (CPR), Kobe, Japan
| | - Fergal J Martin
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Genome Campus, Hinxton, UK.
| | - Wen Wang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an, China.
- CAS Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, China.
| | - Philip C J Donoghue
- Bristol Palaeobiology Group, School of Earth Sciences, University of Bristol, Bristol, UK.
| | - Yong E Zhang
- Key Laboratory of Zoological Systematics and Evolution and State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
- University of Chinese Academy of Sciences, Beijing, China.
- CAS Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, China.
| | - Juan Pascual-Anaya
- Evolutionary Morphology Laboratory, RIKEN Cluster for Pioneering Research (CPR), Kobe, Japan.
- Department of Animal Biology, Faculty of Science, University of Málaga (UMA), Málaga, Spain.
- Edificio de Bioinnovación, Universidad de Málaga, Málaga, Spain.
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Weimer S, Fraley GS, Orlowski S, Karcher D, Archer G, Pierzchała-Koziec K, Scanes CG. Editorial: Environmental impacts in domestic birds: towards homeostasis, efficiency and well-being. Front Physiol 2023; 14:1281632. [PMID: 37727658 PMCID: PMC10505724 DOI: 10.3389/fphys.2023.1281632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 08/23/2023] [Indexed: 09/21/2023] Open
Affiliation(s)
- Shawna Weimer
- Center for Food Animal Wellbeing, University of Arkansas, Fayetteville, AR, United States
- Center of Excellence in Poultry Science, University of Arkansas, Fayetteville, AR, United States
| | - Gregory S. Fraley
- Department of Animal Sciences, Purdue University, West Lafayette, IN, United States
| | - Sara Orlowski
- Center of Excellence in Poultry Science, University of Arkansas, Fayetteville, AR, United States
| | - Darrin Karcher
- Department of Animal Sciences, Purdue University, West Lafayette, IN, United States
| | - Gregory Archer
- Department of Poultry Science, Texas A&M University, College Station, TX, United States
| | | | - Colin G. Scanes
- Biological Science, University of Wisconsin Milwaukee, Milwaukee, WI, United States
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Klug C, Coates M, Frey L, Greif M, Jobbins M, Pohle A, Lagnaoui A, Haouz WB, Ginter M. Broad snouted cladoselachian with sensory specialization at the base of modern chondrichthyans. SWISS JOURNAL OF PALAEONTOLOGY 2023; 142:2. [PMID: 37009301 PMCID: PMC10050047 DOI: 10.1186/s13358-023-00266-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 02/11/2023] [Indexed: 06/19/2023]
Abstract
UNLABELLED Throughout the Silurian and Devonian, cartilaginous fish successively evolved their specialized skeletal and dental characteristics, and increasingly refined their sensory systems. The Late Devonian shark taxon Maghriboselache mohamezanei gen. et sp. n. from the eastern Anti-Atlas of Morocco is known from multiple specimens preserving most of its skeletal features, which in some instances are preserved in three dimensions. Key details of the dentition, jaws, and pectoral skeleton are shared with the iconic genus Cladoselache. Phylogenetic analyses place the family Cladoselachidae as the sister group of symmoriiforms and these groups as sister group of the holocephalans. Further phylogenetic results corroborate that the initial evolutionary radiation of crown chondrichthyans occurred within or before the Late Devonian. Remarkably, this new stem holocephalan is equipped with a wide snout and large laterally separated nasal capsules: the earliest known example of this condition in the chondrichthyan and (perhaps) gnathostome record. This suggests sensory specialization approaching that of extant broad-rostrum elasmobranchs and represents a significant addition to increasingly apparent ecomorphological diversity among early chondrichthyans. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1186/s13358-023-00266-6.
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Affiliation(s)
- Christian Klug
- Paläontologisches Institut und Museum, University of Zurich, Karl-Schmid-Strasse 4, 8006 Zürich, Switzerland
| | - Michael Coates
- Department of Organismal Biology and Anatomy, University of Chicago, 1027 E. 57Th St., Chicago, 60637 USA
| | - Linda Frey
- Paläontologisches Institut und Museum, University of Zurich, Karl-Schmid-Strasse 4, 8006 Zürich, Switzerland
| | - Merle Greif
- Paläontologisches Institut und Museum, University of Zurich, Karl-Schmid-Strasse 4, 8006 Zürich, Switzerland
| | - Melina Jobbins
- Paläontologisches Institut und Museum, University of Zurich, Karl-Schmid-Strasse 4, 8006 Zürich, Switzerland
| | - Alexander Pohle
- Institute for Geology, Mineralogy, and Geophysics, Ruhr University Bochum, Universitätsstraβe 150, 44801 Bochum, Germany
| | - Abdelouahed Lagnaoui
- Interdisciplinary Research Laboratory in Sciences, Education and Training, Higher School of Education and Training Berrechid (ESEFB), Hassan First University, Avenue de l’Université, B.P:218, 26100 Berrechid, Morocco
- Laboratory of Stratigraphy of Oil-and-Gas Bearing Reservoirs, Department of Paleontology and Stratigraphy, Institute of Geology and Petroleum Technologies, Federal University, Kremlyovskaya Str. 18, 420008 Kazan, Volga Region Russia
| | - Wahiba Bel Haouz
- Laboratory of Stratigraphy of Oil-and-Gas Bearing Reservoirs, Department of Paleontology and Stratigraphy, Institute of Geology and Petroleum Technologies, Federal University, Kremlyovskaya Str. 18, 420008 Kazan, Volga Region Russia
- Geosciences Laboratory, Department of Geology, Faculty of Sciences Ain Chock, Hassan II University, Km 8 Route d’El Jadida, 20100 Casablanca, Morocco
| | - Michal Ginter
- Faculty of Geology, University of Warsaw, Al. Żwirki I Wigury 93, 02-089 Warsaw, Poland
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Greif M, Ferrón HG, Klug C. A new Meckel's cartilage from the Devonian Hangenberg black shale in Morocco and its position in chondrichthyan jaw morphospace. PeerJ 2022; 10:e14418. [PMID: 36573235 PMCID: PMC9789696 DOI: 10.7717/peerj.14418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 10/28/2022] [Indexed: 12/24/2022] Open
Abstract
Fossil chondrichthyan remains are mostly known from their teeth, scales or fin spines only, whereas their cartilaginous endoskeletons require exceptional preservational conditions to become fossilized. While most cartilaginous remains of Famennian (Late Devonian) chondrichthyans were found in older layers of the eastern Anti-Atlas, such fossils were unknown from the Hangenberg black shale (HBS) and only a few chondrichthyan teeth had been found therein previously. Here, we describe a Meckel's cartilage from the Hangenberg black shale in Morocco, which is the first fossil cartilage from these strata. Since no teeth or other skeletal elements have been found in articulation, we used elliptical Fourier (EFA), principal component (PCA), and hierarchical cluster (HCA) analyses to morphologically compare it with 41 chondrichthyan taxa of different size and age and to evaluate its possible systematic affiliation. PCA and HCA position the new specimen closest to some acanthodian and elasmobranch jaws. Accordingly, a holocephalan origin was excluded. The jaw shape as well as the presence of a polygonal pattern, typical for tessellated calcified cartilage, suggest a ctenacanth origin and we assigned the new HBS Meckel's cartilage to the order Ctenacanthiformes with reservations.
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Affiliation(s)
- Merle Greif
- Palaeontological Institute and Museum, University of Zürich, Zürich, Switzerland
| | - Humberto G. Ferrón
- Instituto Cavanilles de Biodiversidad i Biología Evolutiva, Universitat de València, Paterna, Valencia, Spain
| | - Christian Klug
- Palaeontological Institute and Museum, University of Zürich, Zürich, Switzerland
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5
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Atake OJ, Eames BF. Mineralized Cartilage and Bone-Like Tissues in Chondrichthyans Offer Potential Insights Into the Evolution and Development of Mineralized Tissues in the Vertebrate Endoskeleton. Front Genet 2021; 12:762042. [PMID: 35003210 PMCID: PMC8727550 DOI: 10.3389/fgene.2021.762042] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 11/30/2021] [Indexed: 11/25/2022] Open
Abstract
The impregnation of biominerals into the extracellular matrix of living organisms, a process termed biomineralization, gives rise to diverse mineralized (or calcified) tissues in vertebrates. Preservation of mineralized tissues in the fossil record has provided insights into the evolutionary history of vertebrates and their skeletons. However, current understanding of the vertebrate skeleton and of the processes underlying its formation is biased towards biomedical models such as the tetrapods mouse and chick. Chondrichthyans (sharks, skates, rays, and chimaeras) and osteichthyans are the only vertebrate groups with extant (living) representatives that have a mineralized skeleton, but the basal phylogenetic position of chondrichthyans could potentially offer unique insights into skeletal evolution. For example, bone is a vertebrate novelty, but the internal supporting skeleton (endoskeleton) of extant chondrichthyans is commonly described as lacking bone. The molecular and developmental basis for this assertion is yet to be tested. Subperichondral tissues in the endoskeleton of some chondrichthyans display mineralization patterns and histological and molecular features of bone, thereby challenging the notion that extant chondrichthyans lack endoskeletal bone. Additionally, the chondrichthyan endoskeleton demonstrates some unique features and others that are potentially homologous with other vertebrates, including a polygonal mineralization pattern, a trabecular mineralization pattern, and an unconstricted perichordal sheath. Because of the basal phylogenetic position of chondrichthyans among all other extant vertebrates with a mineralized skeleton, developmental and molecular studies of chondrichthyans are critical to flesh out the evolution of vertebrate skeletal tissues, but only a handful of such studies have been carried out to date. This review discusses morphological and molecular features of chondrichthyan endoskeletal tissues and cell types, ultimately emphasizing how comparative embryology and transcriptomics can reveal homology of mineralized skeletal tissues (and their cell types) between chondrichthyans and other vertebrates.
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Affiliation(s)
| | - B. Frank Eames
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, SK, Canada
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Wu Y, Yang Y, Dang H, Xiao H, Huang W, Jia Z, Zhao X, Chen K, Ji N, Guo J, Qin Z, Wang J, Zou J. Molecular identification of Klebsiella pneumoniae and expression of immune genes in infected spotted gar Lepisosteus oculatus. FISH & SHELLFISH IMMUNOLOGY 2021; 119:220-230. [PMID: 34626790 DOI: 10.1016/j.fsi.2021.10.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 10/01/2021] [Accepted: 10/05/2021] [Indexed: 06/13/2023]
Abstract
Spotted gar (Lepisosteus oculatus) is a primitive ray-finned fish which has not undergone the third round whole genome duplication and commonly used as a model to study the evolution of immune genes. In this study, a pathogenic strain of Klebsiella pneumoniae (termed KPY01) was isolated from a diseased spotted gar, based on the Gram-stain and phylogenetic analysis of the 16S rDNA and khe genes. Further, the virulence genes and drug resistance genes were determined and drug sensitivity tests were performed to explore the virulence and drug resistance of the KPY01. Putative biosynthetic gene clusters (BGCs) for the biosynthesis of secondary metabolites were predicted using the anti-SMASH5.0 online genome mining platform. Histopathological analysis revealed that the immune cells were significantly decreased in the white pulp of spleen of fish infected with K. pneumonia and tissue inflammation became apparent. Besides, the expression of cytokines including interleukin (il) -8, il-10, il-12a, il-18 and interferon γ (ifn-γ) were shown to be modulated in the spleen, gills and kidney. Our work provides useful information for further investigation on the virulence of K. pneumoniae and host immune responses to K. pneumoniae infection in fish.
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Affiliation(s)
- Yaxin Wu
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Yibin Yang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Huifeng Dang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Hehe Xiao
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Wenji Huang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Zhao Jia
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Xin Zhao
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Kangyong Chen
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Ning Ji
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Jiahong Guo
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Zhiwei Qin
- Center for Biological Science and Technology, Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai, Zhuhai, 100875, China; Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, Beijing Normal University at Zhuhai, Zhuhai, 100875, China
| | - Junya Wang
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China
| | - Jun Zou
- Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
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7
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Mottequin B, Goolaerts S, Hunt AP, Olive S. The erroneous chondrichthyan egg case assignments from the Devonian: implications for the knowledge on the evolution of the reproductive strategy within chondrichthyans. Naturwissenschaften 2021; 108:36. [PMID: 34432151 DOI: 10.1007/s00114-021-01751-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 08/09/2021] [Accepted: 08/16/2021] [Indexed: 10/20/2022]
Abstract
Spiraxis interstrialis, and its junior synonym Fayolia mourloni, an uppermost Famennian (Upper Devonian) fossil first described as algae and subsequently interpreted as the oldest known chondrichthyan egg case, is reinvestigated based on the discovery of several additional specimens in Belgian collections. New data, in particular from micro-CT imaging, allow to refute S. interstrialis, and by extension also Spiraxis major (the type species of Spiraxis Newberry, non Adams) and Spiraxis randalli from the Famennian of New York and Pennsylvania, as chondrichthyan egg cases. Alternative interpretations of these enigmatic helicoidal fossils are discussed. The first occurrence of oviparity in the fossil record of chondrichthyans is thus not as old as previously thought and is close to the first occurrence of viviparity in this group, both being recognised now in the Mississippian. The question of which of both conditions is plesiomorphic within chondrichthyans, and more widely within vertebrates, is discussed. Also, the presence of the genus Spiraxis in both the USA (east coast) and Belgium reinforces the strong faunal resemblance already observed in both palaeogeographical areas. It suggests important faunal exchanges between these regions of the Euramerica landmass during the Famennian.
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Affiliation(s)
- Bernard Mottequin
- O.D. Earth and History of Life, Royal Belgian Institute of Natural Sciences, rue Vautier 29, 1000, Brussels, Belgium.
| | - Stijn Goolaerts
- O.D. Earth and History of Life & Scientific Service of Heritage, Royal Belgian Institute of Natural Sciences, rue Vautier 29, 1000, Brussels, Belgium
| | - Adrian P Hunt
- Flying Heritage and Combat Armor Museum, 3407 109th St SW, Everett, WA, 98204, USA
| | - Sébastien Olive
- O.D. Earth and History of Life, Royal Belgian Institute of Natural Sciences, rue Vautier 29, 1000, Brussels, Belgium.
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8
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Shark and ray genomics for disentangling their morphological diversity and vertebrate evolution. Dev Biol 2021; 477:262-272. [PMID: 34102168 DOI: 10.1016/j.ydbio.2021.06.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 05/17/2021] [Accepted: 06/01/2021] [Indexed: 11/24/2022]
Abstract
Developmental studies of sharks and rays (elasmobranchs) have provided much insight into the process of morphological evolution of vertebrates. Although those studies are supposedly fueled by large-scale molecular sequencing information, whole-genome sequences of sharks and rays were made available only recently. One compelling difficulty of elasmobranch developmental biology is the low accessibility to embryonic study materials and their slow development. Another limiting factor is the relatively large size of their genomes. Moreover, their large body sizes restrict sustainable captive breeding, while their high body fluid osmolarity prevents reproducible cell culturing for in vitro experimentation, which has also limited our knowledge of their chromosomal organization for validation of genome sequencing products. This article focuses on egg-laying elasmobranch species used in developmental biology and provides an overview of the characteristics of the shark and ray genomes revealed to date. Developmental studies performed on a gene-by-gene basis are also reviewed from a whole-genome perspective. Among the popular regulatory genes studied in developmental biology, I scrutinize shark homologs of Wnt genes that highlight vanishing repertoires in many other vertebrate lineages, as well as Hox genes that underwent an unexpected modification unique to the elasmobranch lineage. These topics are discussed together with insights into the reconstruction of developmental programs in the common ancestor of vertebrates and its subsequent evolutionary trajectories that mark the features that are unique to, and those characterizing the diversity among, cartilaginous fishes.
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9
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Li Q, Cui X, Andreev PS, Zhao W, Wang J, Peng L, Zhu M. Nostolepis scale remains (stem Chondrichthyes) from the Lower Devonian of Qujing, Yunnan, China. PeerJ 2021; 9:e11093. [PMID: 34012725 PMCID: PMC8109008 DOI: 10.7717/peerj.11093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 02/21/2021] [Indexed: 11/25/2022] Open
Abstract
Based initially on microfossils, Nostolepis is one of the first known ‘acanthodians’, which constitute a paraphyletic assemblage of plesiomorphic members of the total group Chondrichthyes. Its wide distribution has potential implications for stratigraphic comparisons worldwide. Six species of Nostolepis have been reported in China, including one species from the Xitun Formation (Lochkovian, Lower Devonian) of Qujing, eastern Yunnan. Acid preparation of rock samples from the Xitun Formation has yielded abundant acanthodian remains. Based on both morphological and histological examinations, here we identify five species of Nostolepis, including two new species. N. qujingensis sp. nov. is characterized by thin scales devoid of the neck anteriorly and the dentine tubules rarely present in the anterior part of the crown. N. digitus sp. nov. is characterized by parallel ridges on anterior and lateral margins of the crown, and the neck constricted and ornamented with pore openings. We extend the duration of N. striata in China from the Pridoli of Silurian (Yulungssu Formation) to the Lower Devonian in Qujing and report the first occurrences of N. amplifica and N. consueta in this region. This study increases the diversity of the Lower Devonian Xitun Fauna and provides a better understanding of the paleogeographic distribution of Nostolepis.
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Affiliation(s)
- Qiang Li
- Research Center of Natural History and Culture, Qujing Normal University, Qujing, China.,Chongqing Institute of Geology and Mineral Resources, Chongqing, China.,Key CAS Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences (CAS), Beijing, China
| | - Xindong Cui
- Key CAS Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences (CAS), Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Plamen Stanislavov Andreev
- Research Center of Natural History and Culture, Qujing Normal University, Qujing, China.,Key CAS Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences (CAS), Beijing, China
| | - Wenjin Zhao
- Key CAS Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences (CAS), Beijing, China.,University of Chinese Academy of Sciences, Beijing, China.,CAS Center for Excellence in Life and Paleoenvironment, Beijing, China
| | - Jianhua Wang
- Research Center of Natural History and Culture, Qujing Normal University, Qujing, China
| | - Lijian Peng
- Research Center of Natural History and Culture, Qujing Normal University, Qujing, China
| | - Min Zhu
- Key CAS Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences (CAS), Beijing, China.,University of Chinese Academy of Sciences, Beijing, China.,CAS Center for Excellence in Life and Paleoenvironment, Beijing, China
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10
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Endocast and Bony Labyrinth of a Devonian "Placoderm" Challenges Stem Gnathostome Phylogeny. Curr Biol 2021; 31:1112-1118.e4. [PMID: 33508218 DOI: 10.1016/j.cub.2020.12.046] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 11/24/2020] [Accepted: 12/23/2020] [Indexed: 11/20/2022]
Abstract
Our understanding of the earliest evolution of jawed vertebrates depends on a credible phylogenetic framework for the jawed stem gnathostomes collectively known as "placoderms".1 However, their relationships, and whether placoderms represent a single radiation or a paraphyletic array, remain contentious.2-13 This uncertainty is compounded by an uneven understanding of anatomy across the group, particularly of the phylogenetically informative braincase and brain cavity-endocast. Based on new tomographic data, we here describe the endocast and bony labyrinth of Brindabellaspis stensioi from the Early Devonian of New South Wales.14 The taxon was commonly recovered as branching near the base of placoderms.5-9,11,12,15-17 Previous studies of Brindabellaspis emphasized its resemblances with fossil jawless fishes in the braincase anatomy14 and endocast proportions1,18 and its distinctive features were interpreted as autapomorphies, such as the elongated premedian region.19 Although our three-dimensional data confirmed the resemblance of its endocast to those of jawless vertebrates, we discovered that the inner ear and endolymphatic complex display a repertoire of previously unrecognized characters close to modern or crown-group jawed vertebrates, including a pronounced sinus superior and a vertical duct that connects the endolymphatic sac and the labyrinth cavity. Both parsimony and Bayesian analyses suggest that prevailing hypotheses of placoderm relationships are unstable, with newly revealed anatomy pointing to a radical revision of early gnathostome evolution. Our results call into question the appropriateness of arthrodire-like placoderms as models of primitive gnathostome anatomy and raise questions of homology relating to key cranial features.
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11
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King B, Rücklin M. A Bayesian approach to dynamic homology of morphological characters and the ancestral phenotype of jawed vertebrates. eLife 2020; 9:e62374. [PMID: 33274719 PMCID: PMC7793628 DOI: 10.7554/elife.62374] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 12/03/2020] [Indexed: 12/22/2022] Open
Abstract
Phylogenetic analysis of morphological data proceeds from a fixed set of primary homology statements, the character-by-taxon matrix. However, there are cases where multiple conflicting homology statements can be justified from comparative anatomy. The upper jaw bones of placoderms have traditionally been considered homologous to the palatal vomer-dermopalatine series of osteichthyans. The discovery of 'maxillate' placoderms led to the alternative hypothesis that 'core' placoderm jaw bones are premaxillae and maxillae lacking external (facial) laminae. We introduce a BEAST2 package for simultaneous inference of homology and phylogeny, and find strong evidence for the latter hypothesis. Phenetic analysis of reconstructed ancestors suggests that maxillate placoderms are the most plesiomorphic known gnathostomes, and the shared cranial architecture of arthrodire placoderms, maxillate placoderms and osteichthyans is inherited. We suggest that the gnathostome ancestor possessed maxillae and premaxillae with facial and palatal laminae, and that these bones underwent divergent evolutionary trajectories in placoderms and osteichthyans.
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12
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Frey L, Coates MI, Tietjen K, Rücklin M, Klug C. A symmoriiform from the Late Devonian of Morocco demonstrates a derived jaw function in ancient chondrichthyans. Commun Biol 2020; 3:681. [PMID: 33203942 PMCID: PMC7672094 DOI: 10.1038/s42003-020-01394-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 10/16/2020] [Indexed: 12/02/2022] Open
Abstract
The Palaeozoic record of chondrichthyans (sharks, rays, chimaeras, extinct relatives) and thus our knowledge of their anatomy and functional morphology is poor because of their predominantly cartilaginous skeletons. Here, we report a previously undescribed symmoriiform shark, Ferromirum oukherbouchi, from the Late Devonian of the Anti-Atlas. Computed tomography scanning reveals the undeformed shape of the jaws and hyoid arch, which are of a kind often used to represent primitive conditions for jawed vertebrates. Of critical importance, these closely fitting cartilages preclude the repeatedly hypothesized presence of a complete gill between mandibular and hyoid arches. We show that the jaw articulation is specialized and drives mandibular rotation outward when the mouth opens, and inward upon closure. The resultant eversion and inversion of the lower dentition presents a greater number of teeth to prey through the bite-cycle. This suggests an increased functional and ecomorphological disparity among chondrichthyans preceding and surviving the end-Devonian extinctions. Frey and colleagues describe a new fossil shark from the Late Devonian of Morocco in which the specialized jaw articulation is unusually well preserved. Biomechanical modelling reveals that the mandible rolled throughout its movement arc, engaging more of its tooth battery in a clutching bite action.
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Affiliation(s)
- Linda Frey
- Paläontologisches Institut und Museum, University of Zurich, Karl-Schmid-Strasse 4, CH-8006, Zürich, Switzerland.
| | - Michael I Coates
- Department of Organismal Biology and Anatomy, University of Chicago, 1027 E. 57th St., Chicago, IL, 60637, USA
| | - Kristen Tietjen
- Biodiversity Institute, University of Kansas, 1345 Jayhawk Blvd, Lawrence, KS, 66045, USA
| | - Martin Rücklin
- Naturalis Biodiversity Center, Vertebrate Evolution Development and Ecology, Postbus 9517, 2300 RA, Leiden, The Netherlands
| | - Christian Klug
- Paläontologisches Institut und Museum, University of Zurich, Karl-Schmid-Strasse 4, CH-8006, Zürich, Switzerland.
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13
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Endochondral bone in an Early Devonian 'placoderm' from Mongolia. Nat Ecol Evol 2020; 4:1477-1484. [PMID: 32895518 DOI: 10.1038/s41559-020-01290-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 07/23/2020] [Indexed: 11/08/2022]
Abstract
Endochondral bone is the main internal skeletal tissue of nearly all osteichthyans-the group comprising more than 60,000 living species of bony fishes and tetrapods. Chondrichthyans (sharks and their kin) are the living sister group of osteichthyans and have primarily cartilaginous endoskeletons, long considered the ancestral condition for all jawed vertebrates (gnathostomes). The absence of bone in modern jawless fishes and the absence of endochondral ossification in early fossil gnathostomes appear to lend support to this conclusion. Here we report the discovery of extensive endochondral bone in Minjinia turgenensis, a new genus and species of 'placoderm'-like fish from the Early Devonian (Pragian) of western Mongolia described using X-ray computed microtomography. The fossil consists of a partial skull roof and braincase with anatomical details providing strong evidence of placement in the gnathostome stem group. However, its endochondral space is filled with an extensive network of fine trabeculae resembling the endochondral bone of osteichthyans. Phylogenetic analyses place this new taxon as a proximate sister group of the gnathostome crown. These results provide direct support for theories of generalized bone loss in chondrichthyans. Furthermore, they revive theories of a phylogenetically deeper origin of endochondral bone and its absence in chondrichthyans as a secondary condition.
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14
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Gess RW, Whitfield AK. Estuarine fish and tetrapod evolution: insights from a Late Devonian (Famennian) Gondwanan estuarine lake and a southern African Holocene equivalent. Biol Rev Camb Philos Soc 2020; 95:865-888. [PMID: 32059074 DOI: 10.1111/brv.12590] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 01/31/2020] [Accepted: 02/05/2020] [Indexed: 01/31/2023]
Abstract
The Waterloo Farm lagerstätte in South Africa provides a uniquely well-preserved record of a Latest Devonian estuarine ecosystem. Ecological evidence from it is reviewed, contextualised, and compared with that available from the analogous Swartvlei estuarine lake, with a particular emphasis on their piscean inhabitants. Although the taxonomic affinities of the estuarine species are temporally very different, the overall patterns of utilisation prove to be remarkably congruent, with similar trophic structures. Significantly, both systems show evidence of widespread use of estuaries as fish nurseries by both resident and marine migrant taxa. Holocene estuaries are almost exclusively utilised by actinopterygians which are overwhelmingly dominated by oviparous species. Complex strategies are utilised by estuarine resident species to avoid exposure of eggs to environmental stresses that characterize these systems. By contrast, many of the groups utilising Devonian estuaries were likely live bearers, potentially allowing them to avoid the challenges faced by oviparous taxa. This may have contributed to dominance of these systems by non-actinoptergians prior to the End Devonian Mass Extinction. The association of early aquatic tetrapods at Waterloo Farm with a fish nursery environment is consistent with findings from North America, Belgium and Russia, and may be implied by the estuarine settings of a number of other Devonian tetrapods. Tetrapods apparently replace their sister group, the elpistostegids, in estuaries with both groups having been postulated to be adaptated to shallow water habitats where they could access small piscean prey. Correlation of tetrapods (and elpistostegids) with fish nursery areas in the Late Devonian lends strong support to this hypothesis, suggesting that adaptations permitting improved access to the abundant juvenile fish within the littoral zone of estuarine lakes and continental water bodies may have been pivotal in the evolution of tetrapods.
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Affiliation(s)
- Robert W Gess
- Albany Museum and Geology Department, Rhodes University, P.O. Box 94, Makhanda/Grahamstown, South Africa
| | - Alan K Whitfield
- South African Institute for Aquatic Biodiversity (SAIAB), Private Bag 1015, Makhanda/Grahamstown, South Africa
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15
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Doeland M, Couzens AMC, Donoghue PCJ, Rücklin M. Tooth replacement in early sarcopterygians. ROYAL SOCIETY OPEN SCIENCE 2019; 6:191173. [PMID: 31827852 PMCID: PMC6894600 DOI: 10.1098/rsos.191173] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 10/22/2019] [Indexed: 06/10/2023]
Abstract
Teeth were an important innovation in vertebrate evolution but basic aspects of early dental evolution remain poorly understood. Teeth differ from other odontode organs, like scales, in their organized, sequential pattern of replacement. However, tooth replacement patterns also vary between the major groups of jawed vertebrates. Although tooth replacement in stem-osteichthyans and extant species has been intensively studied it has been difficult to resolve scenarios for the evolution of osteichthyan tooth replacement because of a dearth of evidence from living and fossil sarcopterygian fishes. Here we provide new anatomical data informing patterns of tooth replacement in the Devonian sarcopterygian fishes Onychodus, Eusthenopteron and Tiktaalik and the living coelacanth Latimeria based on microfocus- and synchrotron radiation-based X-ray microtomography. Early sarcopterygians generated replacement teeth on the jaw surface in a pattern similar to stem-osteichthyans, with damaged teeth resorbed and replacement teeth developed on the surface of the bone. However, resorption grades and development of replacement teeth vary spatially and temporally within the jaw. Particularly in Onychodus, where teeth were also shed through anterior rotation and resorption of bone at the base of the parasymphyseal tooth whorl, with new teeth added posteriorly. As tooth whorls are also present in more stem-osteichthyans, and statodont tooth whorls are present among acanthodians (putative stem-chondrichthyans), rotational replacement of the anterior dentition may be a stem-osteichthyan character. Our results suggest a more complex evolutionary history of tooth replacement.
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Affiliation(s)
- Mark Doeland
- Naturalis Biodiversity Center, Postbus 9517, 2300 RA Leiden, The Netherlands
- Institute of Biology, Universiteit Leiden, Silviusweg 72, 2333 BE Leiden, The Netherlands
| | - Aidan M. C. Couzens
- Naturalis Biodiversity Center, Postbus 9517, 2300 RA Leiden, The Netherlands
| | - Philip C. J. Donoghue
- School of Earth Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Martin Rücklin
- Naturalis Biodiversity Center, Postbus 9517, 2300 RA Leiden, The Netherlands
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16
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The pharynx of the stem-chondrichthyan Ptomacanthus and the early evolution of the gnathostome gill skeleton. Nat Commun 2019; 10:2050. [PMID: 31053719 PMCID: PMC6499890 DOI: 10.1038/s41467-019-10032-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 04/10/2019] [Indexed: 11/25/2022] Open
Abstract
The gill apparatus of gnathostomes (jawed vertebrates) is fundamental to feeding and ventilation and a focal point of classic hypotheses on the origin of jaws and paired appendages. The gill skeletons of chondrichthyans (sharks, batoids, chimaeras) have often been assumed to reflect ancestral states. However, only a handful of early chondrichthyan gill skeletons are known and palaeontological work is increasingly challenging other pre-supposed shark-like aspects of ancestral gnathostomes. Here we use computed tomography scanning to image the three-dimensionally preserved branchial apparatus in Ptomacanthus, a 415 million year old stem-chondrichthyan. Ptomacanthus had an osteichthyan-like compact pharynx with a bony operculum helping constrain the origin of an elongate elasmobranch-like pharynx to the chondrichthyan stem-group, rather than it representing an ancestral condition of the crown-group. A mixture of chondrichthyan-like and plesiomorphic pharyngeal patterning in Ptomacanthus challenges the idea that the ancestral gnathostome pharynx conformed to a morphologically complete ancestral type. Our understanding of the origin of jaws is hampered by the poor fossil preservation of pharyngeal morphology. Here, Dearden et al. provide insight into the skull conditions of early jawed vertebrates through three-dimensional computed tomography imaging of a 415 million year old stem-chondrichthyan.
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17
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Coates MI, Finarelli JA, Sansom IJ, Andreev PS, Criswell KE, Tietjen K, Rivers ML, La Riviere PJ. An early chondrichthyan and the evolutionary assembly of a shark body plan. Proc Biol Sci 2019; 285:rspb.2017.2418. [PMID: 29298937 DOI: 10.1098/rspb.2017.2418] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 11/29/2017] [Indexed: 11/12/2022] Open
Abstract
Although relationships among the major groups of living gnathostomes are well established, the relatedness of early jawed vertebrates to modern clades is intensely debated. Here, we provide a new description of Gladbachus, a Middle Devonian (Givetian approx. 385-million-year-old) stem chondrichthyan from Germany, and one of the very few early chondrichthyans in which substantial portions of the endoskeleton are preserved. Tomographic and histological techniques reveal new details of the gill skeleton, hyoid arch and jaws, neurocranium, cartilage, scales and teeth. Despite many features resembling placoderm or osteichthyan conditions, phylogenetic analysis confirms Gladbachus as a stem chondrichthyan and corroborates hypotheses that all acanthodians are stem chondrichthyans. The unfamiliar character combination displayed by Gladbachus, alongside conditions observed in acanthodians, implies that pre-Devonian stem chondrichthyans are severely under-sampled and strongly supports indications from isolated scales that the gnathostome crown group originated at the latest by the early Silurian (approx. 440 Ma). Moreover, phylogenetic results highlight the likely convergent evolution of conventional chondrichthyan conditions among earliest members of this primary gnathostome division, while skeletal morphology points towards the likely suspension feeding habits of Gladbachus, suggesting a functional origin of the gill slit condition characteristic of the vast majority of living and fossil chondrichthyans.
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Affiliation(s)
- Michael I Coates
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637-1508, USA
| | - John A Finarelli
- UCD School of Biology and Environmental Science, UCD Science Education and Research Centre (West), UCD Earth Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Ivan J Sansom
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Plamen S Andreev
- School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Katharine E Criswell
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637-1508, USA.,Department of Zoology, Cambridge University, Cambridge CB2 3EJ, UK
| | - Kristen Tietjen
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637-1508, USA
| | - Mark L Rivers
- Center for Advanced Radiation Sources, University of Chicago, Chicago, IL 60637-1508, USA
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18
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DeLaurier A. Evolution and development of the fish jaw skeleton. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2018; 8:e337. [PMID: 30378758 DOI: 10.1002/wdev.337] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 09/25/2018] [Accepted: 09/27/2018] [Indexed: 12/18/2022]
Abstract
The evolution of the jaw represents a key innovation in driving the diversification of vertebrate body plans and behavior. The pharyngeal apparatus originated as gill bars separated by slits in chordate ancestors to vertebrates. Later, with the acquisition of neural crest, pharyngeal arches gave rise to branchial basket cartilages in jawless vertebrates (agnathans), and later bone and cartilage of the jaw, jaw support, and gills of jawed vertebrates (gnathostomes). Major events in the evolution of jaw structure from agnathans to gnathostomes include axial regionalization of pharyngeal elements and formation of a jaw joint. Hox genes specify the anterior-posterior identity of arches, and edn1, dlx, hand2, Jag1b-Notch2 signaling, and Nr2f factors specify dorsal-ventral identity. The formation of a jaw joint, an important step in the transition from an un-jointed pharynx in agnathans to a hinged jaw in gnathostomes involves interaction between nkx3.2, hand2, and barx1 factors. Major events in jaw patterning between fishes and reptiles include changes to elements of the second pharyngeal arch, including a loss of opercular and branchiostegal ray bones and transformation of the hyomandibula into the stapes. Further changes occurred between reptiles and mammals, including the transformation of the articular and quadrate elements of the jaw joint into the malleus and incus of the middle ear. Fossils of transitional jaw phenotypes can be analyzed from a developmental perspective, and there exists potential to use genetic manipulation techniques in extant taxa to test hypotheses about the evolution of jaw patterning in ancient vertebrates. This article is categorized under: Comparative Development and Evolution > Evolutionary Novelties Early Embryonic Development > Development to the Basic Body Plan Comparative Development and Evolution > Body Plan Evolution.
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Affiliation(s)
- April DeLaurier
- Department of Biology and Geology, University of South Carolina Aiken, Aiken, South Carolina
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19
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King B, Young GC, Long JA. New information on Brindabellaspis stensioi Young, 1980, highlights morphological disparity in Early Devonian placoderms. ROYAL SOCIETY OPEN SCIENCE 2018; 5:180094. [PMID: 30110452 PMCID: PMC6030278 DOI: 10.1098/rsos.180094] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 04/26/2018] [Indexed: 06/08/2023]
Abstract
Acid-prepared specimens of the placoderm Brindabellaspis stensioi (Early Devonian of New South Wales, Australia) revealed placoderm endocranial anatomy in unprecedented detail. Brindabellaspis has become a key taxon in discussions of early gnathostome phylogeny, and the question of placoderm monophyly versus paraphyly. The anterior orientation of the facial nerve and related hyoid arch structures in this taxon resemble fossil osteostracans (jawless vertebrates) rather than other early gnathostomes. New specimens of Brindabellaspis now reveal the previously unknown anterior region of the skull, including an exceptionally elongate premedian bone forming a long rostrum, supported by a thin extension of the postethmo-occipital unit of the braincase. Lateral overlap surfaces indicate an unusual anterior position for the jaws. Digital rendering of a synchrotron radiation scan reveals a uniquely specialized ethmoid commissure sensory canal, doubled back and fused into a midline canal. The visceral surface of the premedian bone has a plexus of perichondral bone canals. An updated skull roof reconstruction of Brindabellaspis adds to the highly variable dermal skull patterns of the probably non-monophyletic 'acanthothoracids'. The unusual morphology revealed by the new specimens suggests that the earliest known reef fish fauna contained a diverse range of fishes with specialized ecological roles.
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Affiliation(s)
- Benedict King
- College of Science and Engineering, Flinders University, PO Box 2100, Adelaide, South Australia 5001, Australia
- Naturalis Biodiversity Center, Postbus 9517, 2300 RA Leiden, The Netherlands
| | - Gavin C. Young
- Research School of Physics and Engineering (RSPE), Australian National University, Canberra 0200, Australian Capital Territory, Australia
- Australian Museum Research Institute, 1 Williams Street, Sydney New South Wales 2010, Australia
| | - John A. Long
- College of Science and Engineering, Flinders University, PO Box 2100, Adelaide, South Australia 5001, Australia
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20
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Clement AM, King B, Giles S, Choo B, Ahlberg PE, Young GC, Long JA. Neurocranial anatomy of an enigmatic Early Devonian fish sheds light on early osteichthyan evolution. eLife 2018; 7:e34349. [PMID: 29807569 PMCID: PMC5973833 DOI: 10.7554/elife.34349] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 04/27/2018] [Indexed: 11/13/2022] Open
Abstract
The skull of 'Ligulalepis' from the Early Devonian of Australia (AM-F101607) has significantly expanded our knowledge of early osteichthyan anatomy, but its phylogenetic position has remained uncertain. We herein describe a second skull of 'Ligulalepis' and present micro-CT data on both specimens to reveal novel anatomical features, including cranial endocasts. Several features previously considered to link 'Ligulalepis' with actinopterygians are now considered generalized osteichthyan characters or of uncertain polarity. The presence of a lateral cranial canal is shown to be variable in its development between specimens. Other notable new features include the presence of a pineal foramen, the some detail of skull roof sutures, the shape of the nasal capsules, a placoderm-like hypophysial vein, and a chondrichthyan-like labyrinth system. New phylogenetic analyses place 'Ligulalepis' as a stem osteichthyan, specifically as the sister taxon to 'psarolepids' plus crown osteichthyans. The precise position of 'psarolepids' differs between parsimony and Bayesian analyses.
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Affiliation(s)
- Alice M Clement
- College of Science and EngineeringFlinders UniversityAdelaideAustralia
- Department of Organismal BiologyEvolutionary Biology Centre, Uppsala UniversityUppsalaSweden
- Department of SciencesMuseum VictoriaMelbourneAustralia
| | - Benedict King
- College of Science and EngineeringFlinders UniversityAdelaideAustralia
- Naturalis Biodiversity CenterLeidenNetherlands
| | - Sam Giles
- Department of Earth SciencesUniversity of OxfordOxfordUnited Kingdom
| | - Brian Choo
- College of Science and EngineeringFlinders UniversityAdelaideAustralia
| | - Per E Ahlberg
- Department of Organismal BiologyEvolutionary Biology Centre, Uppsala UniversityUppsalaSweden
| | - Gavin C Young
- Department of Applied MathematicsResearch School of Physics & Engineering, Australian National UniversityCanberraAustralia
- Australian Museum Research InstituteSydneyAustralia
| | - John A Long
- College of Science and EngineeringFlinders UniversityAdelaideAustralia
- Department of SciencesMuseum VictoriaMelbourneAustralia
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21
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Wang Y, Zhu M. Redescription of Phymolepis cuifengshanensis (Antiarcha: Yunnanolepididae) using high-resolution computed tomography and new insights into anatomical details of the endocranium in antiarchs. PeerJ 2018; 6:e4808. [PMID: 29868260 PMCID: PMC5978403 DOI: 10.7717/peerj.4808] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 04/30/2018] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Yunnanolepidoids constitute either the most basal consecutive segments or the most primitive clade of antiarchs, a highly diversified jawed vertebrate group from the Silurian and Early Devonian periods. Although the general morphology of yunnanolepidoids is well established, their endocranial features remain largely unclear, thus hindering our further understanding of antiarch evolution, and early gnathostome evolution. Phymolepis cuifengshanensis, a yunnanolepidoid from the Early Devonian of southwestern China, is re-described in detail to reveal the information on endocranial anatomy and additional morphological data of head and trunk shields. METHODS We scanned the material of P. cuifengshanensis using high-resolution computed tomography and generated virtual restorations to show the internal morphology of its dermal shield. The dorsal aspect of endocranium in P. cuifengshanensis was therefore inferred. The phylogenetic analysis of antiarchs was conducted based on a revised and expanded dataset that incorporates 10 new cranial characters. RESULTS The lateroventral fossa of trunk shield and Chang's apparatus are three-dimensionally restored in P. cuifengshanensis. The canal that is positioned just anterior to the internal cavity of Chang's apparatus probably corresponds to the rostrocaudal canal of euantiarchs. The endocranial morphology of P. cuifengshanensis corroborates a general pattern for yunnanolepidoids with additional characters distinguishing them from sinolepids and euantiarchs, such as a developed cranio-spinal process, an elongated endolymphatic duct, and a long occipital portion. DISCUSSION In light of new data from Phymolepis and Yunnanolepis, we summarized the morphology on the visceral surface of head shield in antiarchs, and formulated an additional 10 characters for the phylogenetic analysis. These cranial characters exhibit a high degree of morphological disparity between major subgroups of antiarchs, and highlight the endocranial character evolution in antiarchs.
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Affiliation(s)
- Yajing Wang
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Life and Paleoenvironment, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Min Zhu
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Life and Paleoenvironment, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
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22
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Castiello M, Brazeau MD. Neurocranial anatomy of the petalichthyid placoderm Shearsbyaspis oepiki Young revealed by X-ray computed microtomography. PALAEONTOLOGY 2018; 61:369-389. [PMID: 29937580 PMCID: PMC5993267 DOI: 10.1111/pala.12345] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 11/20/2017] [Indexed: 06/08/2023]
Abstract
Stem-group gnathostomes reveal the sequence of character acquisition in the origin of modern jawed vertebrates. The petalichthyids are placoderm-grade stem-group gnathostomes known from both isolated skeletal material and rarer articulated specimens of one genus. They are of particular interest because of anatomical resemblances with osteostracans, the jawless sister group of jawed vertebrates. Because of this, they have become central to debates on the relationships of placoderms and the primitive cranial architecture of gnathostomes. However, among petalichthyids, only the braincase of Macropetalichthys has been studied in detail, and the diversity of neurocranial morphology in this group remains poorly documented. Using X-ray computed microtomography, we investigated the endocranial morphology of Shearsbyaspis oepiki Young, a three-dimensionally preserved petalichthyid from the Early Devonian of Taemas-Wee Jasper, Australia. We generated virtual reconstructions of the external endocranial surfaces, orbital walls and cranial endocavity, including canals for major nerves and blood vessels. The neurocranium of Shearsbyaspis resembles that of Macropetalichthys, particularly in the morphology of the brain cavity, nerves and blood vessels. Many characters, including the morphology of the pituitary vein canal and the course of the trigeminal nerve, recall the morphology of osteostracans. Additionally, the presence of a parasphenoid in Shearsbyaspis (previously not known with confidence outside of arthrodires and osteichthyans) raises some questions about current proposals of placoderm paraphyly. Our detailed description of this specimen adds to the known morphological diversity of petalichthyids, and invites critical reappraisal of the phylogenetic relationships of placoderms.
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Affiliation(s)
- Marco Castiello
- Department of Life Sciences Imperial College London Silwood Campus, Buckhurst Road Ascot SL5 7PY UK
| | - Martin D Brazeau
- Department of Life Sciences Imperial College London Silwood Campus, Buckhurst Road Ascot SL5 7PY UK
- Department of Earth Sciences Natural History Museum London SW7 5BD UK
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23
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Denton JSS, Goolsby EW. Measuring inferential importance of taxa using taxon influence indices. Ecol Evol 2018; 8:4484-4494. [PMID: 29760889 PMCID: PMC5938459 DOI: 10.1002/ece3.3941] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 01/14/2018] [Accepted: 01/31/2018] [Indexed: 11/30/2022] Open
Abstract
Assessing the importance of different taxa for inferring evolutionary history is a critical, but underutilized, aspect of systematics. Quantifying the importance of all taxa within a dataset provides an empirical measurement that can establish a ranking of extant taxa for ecological study and/or quantify the relative importance of newly announced or redescribed specimens to enable the disentangling of novelty and inferential influence. Here, we illustrate the use of taxon influence indices through analysis of both molecular and morphological datasets, introducing a modified Bayesian approach to the taxon influence index that accounts for model and topological uncertainty. Quantification of taxon influence using the Bayesian approach produced clear rankings for both dataset types. Bayesian taxon rankings differed from maximum likelihood (ML)‐derived rankings from a mitogenomic dataset, and the highest ranking taxa exhibited the largest interquartile range in influence estimate, suggesting variance in the estimate must be taken into account when the ranking of taxa is the feature of interest. Application of the Bayesian taxon influence index to a recent morphological analysis of the Tully Monster (Tullimonstrum) reveals that it exhibits consistently low inferential importance across two recent treatments of the taxon with alternative character codings. These results lend support to the idea that taxon influence indices may be robust to character coding and therefore effective for morphological analyses. These results underscore a need for the development of approaches to, and application of, taxon influence analyses both for the purpose of establishing robust rankings for future inquiry and for explicitly quantifying the importance of individual taxa. Quantifying the importance of individual taxa refocuses debates in morphological studies from questions of character choice/significance and taxon sampling to explicitly analytical techniques, and guides discussion of the context of new discoveries.
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Affiliation(s)
- John S S Denton
- Department of Vertebrate Paleontology American Museum of Natural History New York NY USA
| | - Eric W Goolsby
- Department of Ecology and Evolutionary Biology Yale University New Haven CT USA
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24
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King B, Qiao T, Lee MSY, Zhu M, Long JA. Bayesian Morphological Clock Methods Resurrect Placoderm Monophyly and Reveal Rapid Early Evolution in Jawed Vertebrates. Syst Biol 2018; 66:499-516. [PMID: 27920231 DOI: 10.1093/sysbio/syw107] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 11/18/2016] [Indexed: 11/13/2022] Open
Abstract
The phylogeny of early gnathostomes provides an important framework for understanding one of the most significant evolutionary events, the origin and diversification of jawed vertebrates. A series of recent cladistic analyses have suggested that the placoderms, an extinct group of armoured fish, form a paraphyletic group basal to all other jawed vertebrates. We revised and expanded this morphological data set, most notably by sampling autapomorphies in a similar way to parsimony-informative traits, thus ensuring this data (unlike most existing morphological data sets) satisfied an important assumption of Bayesian tip-dated morphological clock approaches. We also found problems with characters supporting placoderm paraphyly, including character correlation and incorrect codings. Analysis of this data set reveals that paraphyly and monophyly of core placoderms (excluding maxillate forms) are essentially equally parsimonious. The two alternative topologies have different root positions for the jawed vertebrates but are otherwise similar. However, analysis using tip-dated clock methods reveals strong support for placoderm monophyly, due to this analysis favoring trees with more balanced rates of evolution. Furthermore, enforcing placoderm paraphyly results in higher levels and unusual patterns of rate heterogeneity among branches, similar to that generated from simulated trees reconstructed with incorrect root positions. These simulations also show that Bayesian tip-dated clock methods outperform parsimony when the outgroup is largely uninformative (e.g., due to inapplicable characters), as might be the case here. The analysis also reveals that gnathostomes underwent a rapid burst of evolution during the Silurian period which declined during the Early Devonian. This rapid evolution during a period with few articulated fossils might partly explain the difficulty in ascertaining the root position of jawed vertebrates.
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Affiliation(s)
- Benedict King
- School of Biological Sciences, Flinders University, PO Box 2100, Adelaide, South Australia 5001, Australia
| | - Tuo Qiao
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, China
| | - Michael S Y Lee
- School of Biological Sciences, Flinders University, PO Box 2100, Adelaide, South Australia 5001, Australia.,Earth Sciences Section, South Australian Museum, North Terrace, Adelaide 5000, Australia
| | - Min Zhu
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, China
| | - John A Long
- School of Biological Sciences, Flinders University, PO Box 2100, Adelaide, South Australia 5001, Australia
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25
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Snyder D, Turner S, Burrow CJ, Daeschler EB. “Gyracanthus”sherwoodi(Gnathostomata, Gyracanthidae) from the Late Devonian of North America. PROCEEDINGS OF THE ACADEMY OF NATURAL SCIENCES OF PHILADELPHIA 2017. [DOI: 10.1635/053.165.0111] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Daniel Snyder
- Middle Georgia State University, 1900 Bellevue Road, Dublin, GA, 31021 USA
| | - Susan Turner
- Geoscience Programme, Queensland Museum, 122 Gerler Road, Hendra, Queensland 4011, Australia
| | - Carole J. Burrow
- Geoscience Programme, Queensland Museum, 122 Gerler Road, Hendra, Queensland 4011, Australia
| | - Edward B. Daeschler
- Academy of Natural Sciences of Drexel University, 1900 Benjamin Franklin Parkvay, Philadelphia, PA 19103, USA
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26
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Fish JL. Evolvability of the vertebrate craniofacial skeleton. Semin Cell Dev Biol 2017; 91:13-22. [PMID: 29248471 DOI: 10.1016/j.semcdb.2017.12.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Revised: 11/22/2017] [Accepted: 12/07/2017] [Indexed: 01/05/2023]
Abstract
The skull is a vertebrate novelty. Morphological adaptations of the skull are associated with major evolutionary transitions, including the shift to a predatory lifestyle and the ability to masticate while breathing. These adaptations include the chondrocranium, dermatocranium, articulated jaws, primary and secondary palates, internal choanae, the middle ear, and temporomandibular joint. The incredible adaptive diversity of the vertebrate skull indicates an underlying bauplan that promotes evolvability. Comparative studies in craniofacial development suggest that the craniofacial bauplan includes three secondary organizers, two that are bilaterally placed at the Hinge of the developing jaw, and one situated in the midline of the developing face (the FEZ). These organizers regulate tissue interactions between the cranial neural crest, the neuroepithelium, and facial and pharyngeal epithelia that regulate the development and evolvability of the craniofacial skeleton.
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Affiliation(s)
- Jennifer L Fish
- University of Massachusetts Lowell, Department of Biological Sciences, 198 Riverside St., Olsen Hall 619, Lowell, MA 01854, U.S.A..
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27
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A new stem sarcopterygian illuminates patterns of character evolution in early bony fishes. Nat Commun 2017; 8:1932. [PMID: 29203766 PMCID: PMC5715141 DOI: 10.1038/s41467-017-01801-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 10/16/2017] [Indexed: 11/19/2022] Open
Abstract
Discoveries of putative stem sarcopterygians from the late Silurian and Early Devonian of South China have increased our knowledge of the initial diversification of osteichthyans while also highlighting incongruities in character evolution in this major jawed vertebrate group. Character-rich endocrania are incompletely preserved for early bony fishes, limiting a detailed understanding of complex internal morphology and evolutionary changes in the cranium. Here we report a new sarcopterygian (Ptyctolepis brachynotus gen. et sp. nov.) from the Pragian (Early Devonian) of South China, which preserves a unique example of a completely ossified otoccipital division of the braincase in a stem lobe-finned fish. The hyomandibular facets are paired but lie dorsal to the jugular canal, representing a hitherto unobserved combination of derived and primitive character states. This new taxon prompts a reassessment of early osteichthyan interrelationships, including the phylogenetic placement of psarolepids, which might branch from the osteichthyan—rather than sarcopterygian—stem. Terrestrial vertebrates branched from the lobe-finned fish in the Late Devonian. Here, Lu et al. describe the new lobe-finned fish Ptyctolepis brachynotus dating from the Early Devonian, which preserves a novel combination of cranial characters and suggests revision of evolutionary relationships among bony fish.
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28
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Gai Z, Yu X, Zhu M. The Evolution of the Zygomatic Bone From Agnatha to Tetrapoda. Anat Rec (Hoboken) 2017; 300:16-29. [PMID: 28000409 DOI: 10.1002/ar.23512] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2016] [Revised: 04/23/2016] [Accepted: 06/10/2016] [Indexed: 12/29/2022]
Abstract
Establishing the homology of the zygomatic or jugal bone and tracing its origin and early evolution represents a complex issue because of large morphological gaps between various groups of vertebrates. Using recent paleontological findings, we discuss the deep homology of the zygomatic or jugal bone in stem gnathostomes (placoderms) and examine its homology and modifications in crown gnathostomes (acanthodians, chondrichthyans and osteichthyans). The discovery of the placoderm Entelognathus from the Silurian of China (∼423 million years ago) established that the large dermal plates in placoderms and osteichthyans are homologous. In Entelognathus, the jugal was joined by a new set of bones (premaxilla, maxilla, and lachrymal), marking the first appearance of the typical vertebrate face found in tetrapods including humans. In non-Entelognathus placoderms, the jugal (homologized with the suborbital plate) occupied most of the cheek region and covered the palatoquadrate laterally. In antiarch placoderms (the most basal jawed vertebrates), the jugal (represented by the ventrally positioned mental plate) functioned as part of the upper jaw. In osteichthyans, the preopercular arose as a novel bone and separated the jugal from the opercular in piscine osteichthyans. A single bone in basal osteichthyans, the preopercular may have divided into two or three elements (the preopercular, the squamosal and/or the quadratojugal) in several later osteichthyan groups. Subsequent modifications of the jugal in the fish-tetrapod transition (its enlargement leading to its contact with the quadratojugal and the separation of the squamosal from the maxilla) brought the vertebrate face to the typical model we see in living tetrapods. Anat Rec, 300:16-29, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Zhikun Gai
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences, Beijing, 100044, China
| | - Xiaobo Yu
- Department of Biological Sciences, Kean University, Union, New Jersey
| | - Min Zhu
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences, Beijing, 100044, China
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29
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Chevrinais M, Sire JY, Cloutier R. Unravelling the ontogeny of a Devonian early gnathostome, the "acanthodian" Triazeugacanthus affinis (eastern Canada). PeerJ 2017; 5:e3969. [PMID: 29094000 PMCID: PMC5661438 DOI: 10.7717/peerj.3969] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/08/2017] [Indexed: 12/01/2022] Open
Abstract
The study of vertebrate ontogenies has the potential to inform us of shared developmental patterns and processes among organisms. However, fossilised ontogenies of early vertebrates are extremely rare during the Palaeozoic Era. A growth series of the Late Devonian “acanthodian” Triazeugacanthus affinis, from the Miguasha Fossil-Fish Lagerstätte, is identified as one of the best known early vertebrate fossilised ontogenies given the exceptional preservation, the large size range, and the abundance of specimens. Morphological, morphometric, histological and chemical data are gathered on a growth series of Triazeugacanthus ranging from 4 to 52 mm in total length. The developmental trajectory of this Devonian “acanthodian” is characteristic of fishes showing a direct development with alternating steps and thresholds. Larvae show no squamation but a progressive appearance of cartilaginous neurocranial and vertebral elements, and appendicular elements, whereas juveniles progress in terms of ossification and squamation. The presence of cartilaginous and bony tissues, discriminated on histological and chemical signatures, shows a progressive mineralisation of neurocranial and vertebral elements. Comparison among different body proportions for larvae, juveniles and adults suggest allometric growth in juveniles. Because of the phylogenetic position of “acanthodians”, Triazeugacanthus ontogeny informs us about deep time developmental conditions in gnathostomes.
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Affiliation(s)
- Marion Chevrinais
- Laboratoire de Paléontologie et Biologie évolutive, Université du Québec à Rimouski, Rimouski, Canada
| | - Jean-Yves Sire
- CNRS-UMR 7138-Evolution Paris-Seine IBPS, Université Pierre et Marie Curie, Paris, France
| | - Richard Cloutier
- Laboratoire de Paléontologie et Biologie évolutive, Université du Québec à Rimouski, Rimouski, Canada
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30
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Hu Y, Lu J, Young GC. New findings in a 400 million-year-old Devonian placoderm shed light on jaw structure and function in basal gnathostomes. Sci Rep 2017; 7:7813. [PMID: 28798392 PMCID: PMC5552730 DOI: 10.1038/s41598-017-07674-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 06/30/2017] [Indexed: 11/12/2022] Open
Abstract
Arthodire placoderms have been proposed as the sister group of Chinese ‘maxillate’ placoderms plus all the more crownward gnathostomes. These basal groups provide key information for understanding the early evolution of jaws. Here, we test previous assumptions about placoderm jaw structure and function by using high-resolution computed tomography, digital dissection, and enlarged 3D printouts on a unique articulated 400 million-year-old buchanosteid arthrodire. The upper jaw has a double ethmoid and a palatobasal connection, but no otic connection; the dermal bone attachment for the quadrate is different to other placoderms. A separately ossified cartilage behind the mandibular joint is comparable to the interhyal of osteichthyans. Two articular facets on the braincase associated with the hyomandibular nerve foramen supported a possible epihyal element and a separate opercular cartilage. Reassembling and manipulating 3D printouts demonstrates the limits of jaw kenetics. The new evidence indicates unrecognized similarities in jaw structure between arthrodires and osteichthyans, and will help to clarify the sequence of character acquisition in the evolution of basal gnathostome groups. New details on the hyoid arch will help to reformulate characters that are key in the heated debate of placoderm monophyly or paraphyly.
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Affiliation(s)
- Yuzhi Hu
- Department of Applied Mathematics, Research School of Physics and Engineering, Oliphant Building 60, Australian National University, Canberra, ACT, 2601, Australia.,Research School of Earth Sciences, Building 142 Mills Road, Australian National University, Canberra, ACT, 2601, Australia
| | - Jing Lu
- Department of Applied Mathematics, Research School of Physics and Engineering, Oliphant Building 60, Australian National University, Canberra, ACT, 2601, Australia.,Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, 100044, China
| | - Gavin C Young
- Department of Applied Mathematics, Research School of Physics and Engineering, Oliphant Building 60, Australian National University, Canberra, ACT, 2601, Australia.
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31
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Johanson Z, Smith M, Sanchez S, Senden T, Trinajstic K, Pfaff C. Questioning hagfish affinities of the enigmatic Devonian vertebrate Palaeospondylus. ROYAL SOCIETY OPEN SCIENCE 2017; 4:170214. [PMID: 28791148 PMCID: PMC5541543 DOI: 10.1098/rsos.170214] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 06/20/2017] [Indexed: 06/07/2023]
Abstract
Palaeospondylus gunni Traquair, 1890 is an enigmatic Devonian vertebrate whose taxonomic affinities have been debated since it was first described. Most recently, Palaeospondylus has been identified as a stem-group hagfish (Myxinoidea). However, one character questioning this assignment is the presence of three semicircular canals in the otic region of the cartilaginous skull, a feature of jawed vertebrates. Additionally, new tomographic data reveal that the following characters of crown-group gnathostomes (chondrichthyans + osteichthyans) are present in Palaeospondylus: a longer telencephalic region of the braincase, separation of otic and occipital regions by the otico-occipital fissure, and vertebral centra. As well, a precerebral fontanelle and postorbital articulation of the palatoquadrate are characteristic of certain chondrichthyans. Similarities in the structure of the postorbital process to taxa such as Pucapampella, and possible presence of the ventral cranial fissure, both support a resolution of Pa. gunni as a stem chondrichthyan. The internally mineralized cartilaginous skeleton in Palaeospondylus may represent a stage in the loss of bone characteristic of the Chondrichthyes.
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Affiliation(s)
- Zerina Johanson
- Department of Earth Sciences, Natural History Museum, London, UK
| | - Moya Smith
- Department of Earth Sciences, Natural History Museum, London, UK
- Tissue Engineering and Biophotonics, Dental Institute, King's College London, London, UK
| | - Sophie Sanchez
- Department of Organismal Biology, Uppsala University, Uppsala, Sweden
- European Synchrotron Radiation Facility, Grenoble, France
| | - Tim Senden
- Department of Applied Mathematics, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Kate Trinajstic
- Environment and Agriculture, Curtin University, Kent Street, Bentley, Perth, Australia
| | - Cathrin Pfaff
- Department of Palaeontology, University of Vienna, Vienna, Austria
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32
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Blais SA. Precise occlusion and trophic niche differentiation indicate specialized feeding in Early Devonian jawed vertebrates. Facets (Ott) 2017. [DOI: 10.1139/facets-2016-0030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Acanthodians may represent a paraphyletic assemblage of stem chondrichthyans, stem osteichthyans, stem gnathostomes, or some combination of the three. One of the difficulties in determining the phylogenetic affinities of this group of mostly small, spiny fishes is that several subgroups of acanthodians are represented by relatively little information in the fossil record. It is becoming increasingly apparent that to understand the evolution of gnathostomes, we must understand more about acanthodians. This study uses micro-computed tomography to test hypotheses about acanthodian jaw function, and in doing so provides insight into the form, function, and ecological role of ischnacanthiform acanthodian jaws and teeth from an extraordinary Early Devonian fossil locality in the Northwest Territories of Canada. The results of this study suggest that ischnacanthiform acanthodians may have coexisted by trophic niche differentiation, employing specialized feeding strategies during the Silurian and Early Devonian.
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Affiliation(s)
- Stephanie A. Blais
- Department of Biological Sciences and Laboratory for Vertebrate Palaeontology, University of Alberta, Edmonton, AB T6G 2E9, Canada
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33
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Larouche O, Zelditch ML, Cloutier R. Fin modules: an evolutionary perspective on appendage disparity in basal vertebrates. BMC Biol 2017; 15:32. [PMID: 28449681 PMCID: PMC5406925 DOI: 10.1186/s12915-017-0370-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 03/26/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Fishes are extremely speciose and also highly disparate in their fin configurations, more specifically in the number of fins present as well as their structure, shape, and size. How they achieved this remarkable disparity is difficult to explain in the absence of any comprehensive overview of the evolutionary history of fish appendages. Fin modularity could provide an explanation for both the observed disparity in fin configurations and the sequential appearance of new fins. Modularity is considered as an important prerequisite for the evolvability of living systems, enabling individual modules to be optimized without interfering with others. Similarities in developmental patterns between some of the fins already suggest that they form developmental modules during ontogeny. At a macroevolutionary scale, these developmental modules could act as evolutionary units of change and contribute to the disparity in fin configurations. This study addresses fin disparity in a phylogenetic perspective, while focusing on the presence/absence and number of each of the median and paired fins. RESULTS Patterns of fin morphological disparity were assessed by mapping fin characters on a new phylogenetic supertree of fish orders. Among agnathans, disparity in fin configurations results from the sequential appearance of novel fins forming various combinations. Both median and paired fins would have appeared first as elongated ribbon-like structures, which were the precursors for more constricted appendages. Among chondrichthyans, disparity in fin configurations relates mostly to median fin losses. Among actinopterygians, fin disparity involves fin losses, the addition of novel fins (e.g., the adipose fin), and coordinated duplications of the dorsal and anal fins. Furthermore, some pairs of fins, notably the dorsal/anal and pectoral/pelvic fins, show non-independence in their character distribution, supporting expectations based on developmental and morphological evidence that these fin pairs form evolutionary modules. CONCLUSIONS Our results suggest that the pectoral/pelvic fins and the dorsal/anal fins form two distinct evolutionary modules, and that the latter is nested within a more inclusive median fins module. Because the modularity hypotheses that we are testing are also supported by developmental and variational data, this constitutes a striking example linking developmental, variational, and evolutionary modules.
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Affiliation(s)
- Olivier Larouche
- Laboratoire de Paléontologie et de Biologie évolutive, Université du Québec à Rimouski, Rimouski, Québec G5L 3A1 Canada
| | | | - Richard Cloutier
- Laboratoire de Paléontologie et de Biologie évolutive, Université du Québec à Rimouski, Rimouski, Québec G5L 3A1 Canada
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Chevrinais M, Sire JY, Cloutier R. From body scale ontogeny to species ontogeny: Histological and morphological assessment of the Late Devonian acanthodian Triazeugacanthus affinis from Miguasha, Canada. PLoS One 2017; 12:e0174655. [PMID: 28403168 PMCID: PMC5389634 DOI: 10.1371/journal.pone.0174655] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 03/13/2017] [Indexed: 11/19/2022] Open
Abstract
Growth series of Palaeozoic fishes are rare because of the fragility of larval and juvenile specimens owing to their weak mineralisation and the scarcity of articulated specimens. This rarity makes it difficult to describe early vertebrate growth patterns and processes in extinct taxa. Indeed, only a few growth series of complete Palaeozoic fishes are available; however, they allow the growth of isolated elements to be described and individual growth from these isolated elements to be inferred. In addition, isolated and in situ scales are generally abundant and well-preserved, and bring information on (1) their morphology and structure relevant to phylogenetic relationships and (2) individual growth patterns and processes relative to species ontogeny. The Late Devonian acanthodian Triazeugacanthusaffinis from the Miguasha Fossil-Lagerstätte preserves one of the best known fossilised ontogenies of early vertebrates because of the exceptional preservation, the large size range, and the abundance of complete specimens. Here, we present morphological, histological, and chemical data on scales from juvenile and adult specimens (scales not being formed in larvae). Histologically, Triazeugacanthus scales are composed of a basal layer of acellular bone housing Sharpey’s fibers, a mid-layer of mesodentine, and a superficial layer of ganoine. Developmentally, scales grow first through concentric addition of mesodentine and bone around a central primordium and then through superposition of ganoine layers. Ontogenetically, scales form first in the region below the dorsal fin spine, then squamation spreads anteriorly and posteriorly, and on fin webs. Phylogenetically, Triazeugacanthus scales show similarities with acanthodians (e.g. “box-in-box” growth), chondrichthyans (e.g. squamation pattern), and actinopterygians (e.g. ganoine). Scale histology and growth are interpreted in the light of a new phylogenetic analysis of gnathostomes supporting acanthodians as stem chondrichthyans.
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Affiliation(s)
| | - Jean-Yves Sire
- UMR 7138-Evolution Paris-Seine, IBPS, Université Pierre et Marie Curie, Paris, France
| | - Richard Cloutier
- Université du Québec à Rimouski, Rimouski, Québec G5L 3A1, Canada
- * E-mail:
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Vaškaninová V, Ahlberg PE. Unique diversity of acanthothoracid placoderms (basal jawed vertebrates) in the Early Devonian of the Prague Basin, Czech Republic: A new look at Radotina and Holopetalichthys. PLoS One 2017; 12:e0174794. [PMID: 28380002 PMCID: PMC5381876 DOI: 10.1371/journal.pone.0174794] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 03/15/2017] [Indexed: 11/21/2022] Open
Abstract
The taxonomy of Early Devonian placoderm material from the Lochkovian and Pragian of the Prague basin, previously attributed to the genera Radotina and Holopetalichthys, is revised. The Pragian species Radotina tesselata Gross 1958 shares detailed similarities with the holotype of the Lochkovian Radotina kosorensis Gross 1950, which is also the holotype of the genus; the assignation of both species to Radotina is supported. However, the Lochkovian material previously attributed to Radotina kosorensis also contains two unrecognised taxa, distinguishable from Radotina at the generic level: these are here named Tlamaspis and Sudaspis. The disputed genus Holopetalichthys, synonymised with Radotina by some previous authors, is shown to be valid. Furthermore, whereas Radotina, Tlamaspis and Sudaspis can all be assigned to the group Acanthothoracii, on the basis of several features including possession of a projecting prenasal region of the endocranium, Holopetalichthys lacks such a region and is probably not an acanthothoracid. Skull roof patterns and other aspects of morphology vary greatly between these taxa. Radotina has a substantially tesselated skull roof, whereas the skull roofs of Tlamaspis and Holopetalichthys appear to lack tesserae altogether. Tlamaspis has an extremely elongated facial region and appears to lack a premedian plate. Sudaspis has a long prenasal region, but unlike Tlamaspis the postnasal face is not elongated. Past descriptions of the braincase of 'Radotina' and the skull roofs of 'Radotina' and 'Holopetalichthys' incorporate data from more than one taxon, giving rise to spurious characterisations including an apparently extreme degree of skull roof variability. These descriptions should all be disregarded.
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Affiliation(s)
- Valéria Vaškaninová
- Institute of Geology and Palaeontology, Faculty of Science, Charles University, Prague, Czech Republic
- * E-mail:
| | - Per E. Ahlberg
- Subdepartment of Evolution and Development, Department of Organismal Biology, Uppsala University, Uppsala, Sweden
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Choo B, Zhu M, Qu Q, Yu X, Jia L, Zhao W. A new osteichthyan from the late Silurian of Yunnan, China. PLoS One 2017; 12:e0170929. [PMID: 28273081 PMCID: PMC5342173 DOI: 10.1371/journal.pone.0170929] [Citation(s) in RCA: 21] [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: 09/20/2016] [Accepted: 01/09/2017] [Indexed: 11/19/2022] Open
Abstract
Our understanding of early gnathostome evolution has been hampered by a generally scant fossil record beyond the Devonian. Recent discoveries from the late Silurian Xiaoxiang Fauna of Yunnan, China, have yielded significant new information, including the earliest articulated osteichthyan fossils from the Ludlow-aged Kuanti Formation. Here we describe the partial postcranium of a new primitive bony fish from the Kuanti Formation that represents the second known taxon of pre-Devonian osteichthyan revealing articulated remains. The new form, Sparalepis tingi gen. et sp. nov., displays similarities with Guiyu and Psarolepis, including a spine-bearing pectoral girdle and a placoderm-like dermal pelvic girdle, a structure only recently identified in early osteichthyans. The squamation with particularly thick rhombic scales shares an overall morphological similarity to that of Psarolepis. However, the anterior flank scales of Sparalepis possess an unusual interlocking system of ventral bulges embraced by dorsal concavities on the outer surfaces. A phylogenetic analysis resolves Sparalepis within a previously recovered cluster of stem-sarcopterygians including Guiyu, Psarolepis and Achoania. The high diversity of osteichthyans from the Ludlow of Yunnan strongly contrasts with other Silurian vertebrate assemblages, suggesting that the South China block may have been an early center of diversification for early gnathostomes, well before the advent of the Devonian "Age of Fishes".
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Affiliation(s)
- Brian Choo
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
- School of Biological Sciences, Flinders University, South Australia, Australia
| | - Min Zhu
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
- College of Earth Science, University of Chinese Academy of Sciences, Beijing, China
| | - Qingming Qu
- Subdepartment of Evolutionary Organismal Biology, Department of Physiology and Developmental Biology, Uppsala University, Uppsala, Sweden
- Center for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa, Canada
| | - Xiaobo Yu
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
- Department of Biological Sciences, Kean University, Union, New Jersey, United States of America
| | - Liantao Jia
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
| | - Wenjin Zhao
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
- College of Earth Science, University of Chinese Academy of Sciences, Beijing, China
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37
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Electrophysiological measures of temporal resolution, contrast sensitivity and spatial resolving power in sharks. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2017; 203:197-210. [DOI: 10.1007/s00359-017-1154-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 02/05/2017] [Accepted: 02/07/2017] [Indexed: 02/07/2023]
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38
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Development of cranial muscles in the actinopterygian fish Senegal bichir,Polypterus senegalusCuvier, 1829. J Morphol 2017; 278:450-463. [DOI: 10.1002/jmor.20636] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 10/31/2016] [Accepted: 11/27/2016] [Indexed: 11/07/2022]
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39
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Dupret V, Sanchez S, Goujet D, Ahlberg PE. The internal cranial anatomy of Romundina stellina Ørvig, 1975 (Vertebrata, Placodermi, Acanthothoraci) and the origin of jawed vertebrates-Anatomical atlas of a primitive gnathostome. PLoS One 2017; 12:e0171241. [PMID: 28170434 PMCID: PMC5295682 DOI: 10.1371/journal.pone.0171241] [Citation(s) in RCA: 21] [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: 08/11/2016] [Accepted: 01/16/2017] [Indexed: 11/19/2022] Open
Abstract
Placoderms are considered as the first jawed vertebrates and constitute a paraphyletic group in the stem-gnathostome grade. The acanthothoracid placoderms are among the phylogenetically most basal and morphologically primitive gnathostomes, but their neurocranial anatomy is poorly understood. Here we present a near-complete three-dimensional skull of Romundina stellina, a small Early Devonian acanthothoracid from the Canadian Arctic Archipelago, scanned with propagation phase contrast microtomography at a 7.46 μm isotropic voxel size at the European Synchrotron Radiation Facility, Grenoble, France. This is the first model of an early gnathostome skull produced using this technique, and as such represents a major advance in objectivity compared to past descriptions of placoderm neurocrania on the basis of grinding series. Despite some loss of material along an oblique crack, most of the internal structures are remarkably preserved, and most of the missing structures can be reconstructed by symmetry. This virtual approach offers the possibility to connect with certainty all the external foramina to the blood and nerve canals and the central structures, and thus identify accurate homologies without destroying the specimen. The high level of detail enables description of the main arterial, venous and nerve canals of the skull, and other perichondrally ossified endocranial structures such as the palatoquadrate articulations, the endocranial cavity and the inner ear cavities. The braincase morphology appears less extreme than that of Brindabellaspis, and is in some respects more reminiscent of a basal arthrodire such as Kujdanowiaspis.
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Affiliation(s)
- Vincent Dupret
- Science for Life Laboratory and Uppsala University, Department of Organismal Biology, Subdepartment of Evolution and Development, Norbyvägen, SE Uppsala, Sweden
- * E-mail: (VD); (PEA)
| | - Sophie Sanchez
- Science for Life Laboratory and Uppsala University, Department of Organismal Biology, Subdepartment of Evolution and Development, Norbyvägen, SE Uppsala, Sweden
- European Synchrotron Radiation Facility, Grenoble, France
| | - Daniel Goujet
- Centre de Recherche sur la Paléobiodiversité et les Paléoenvironnements (CR2P, UMR 7207), Sorbonne Universités, MNHN, CNRS, UPMC-Paris 6, Muséum National d’Histoire Naturelle, Paris, France
| | - Per Erik Ahlberg
- Science for Life Laboratory and Uppsala University, Department of Organismal Biology, Subdepartment of Evolution and Development, Norbyvägen, SE Uppsala, Sweden
- * E-mail: (VD); (PEA)
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40
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Coates MI, Gess RW, Finarelli JA, Criswell KE, Tietjen K. A symmoriiform chondrichthyan braincase and the origin of chimaeroid fishes. Nature 2017; 541:208-211. [DOI: 10.1038/nature20806] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 11/18/2016] [Indexed: 11/09/2022]
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41
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Ryan LA, Hart NS, Collin SP, Hemmi JM. Visual resolution and contrast sensitivity in two benthic sharks. ACTA ACUST UNITED AC 2016; 219:3971-3980. [PMID: 27802139 DOI: 10.1242/jeb.132100] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 10/11/2016] [Indexed: 12/25/2022]
Abstract
Sharks have long been described as having 'poor' vision. They are cone monochromats and anatomical estimates suggest they have low spatial resolution. However, there are no direct behavioural measurements of spatial resolution or contrast sensitivity. This study estimates contrast sensitivity and spatial resolution of two species of benthic sharks, the Port Jackson shark, Heterodontus portusjacksoni, and the brown-banded bamboo shark, Chiloscyllium punctatum, by recording eye movements in response to optokinetic stimuli. Both species tracked moving low spatial frequency gratings with weak but consistent eye movements. Eye movements ceased at 0.38 cycles per degree, even for high contrasts, suggesting low spatial resolution. However, at lower spatial frequencies, eye movements were elicited by low contrast gratings, 1.3% and 2.9% contrast in H portusjacksoni and C. punctatum, respectively. Contrast sensitivity was higher than in other vertebrates with a similar spatial resolving power, which may reflect an adaptation to the relatively low contrast encountered in aquatic environments. Optokinetic gain was consistently low and neither species stabilised the gratings on their retina. To check whether restraining the animals affected their optokinetic responses, we also analysed eye movements in free-swimming C. punctatum We found no eye movements that could compensate for body rotations, suggesting that vision may pass through phases of stabilisation and blur during swimming. As C. punctatum is a sedentary benthic species, gaze stabilisation during swimming may not be essential. Our results suggest that vision in sharks is not 'poor' as previously suggested, but optimised for contrast detection rather than spatial resolution.
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Affiliation(s)
- Laura A Ryan
- School of Animal Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia .,The UWA Oceans Institute, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Nathan S Hart
- School of Animal Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.,The UWA Oceans Institute, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.,Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia
| | - Shaun P Collin
- School of Animal Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.,The UWA Oceans Institute, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Jan M Hemmi
- School of Animal Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.,The UWA Oceans Institute, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
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42
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Zhu M, Ahlberg PE, Pan Z, Zhu Y, Qiao T, Zhao W, Jia L, Lu J. A Silurian maxillate placoderm illuminates jaw evolution. Science 2016; 354:334-336. [DOI: 10.1126/science.aah3764] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 08/31/2016] [Indexed: 11/03/2022]
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43
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Qiao T, King B, Long JA, Ahlberg PE, Zhu M. Early Gnathostome Phylogeny Revisited: Multiple Method Consensus. PLoS One 2016; 11:e0163157. [PMID: 27649538 PMCID: PMC5029804 DOI: 10.1371/journal.pone.0163157] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 09/02/2016] [Indexed: 12/02/2022] Open
Abstract
A series of recent studies recovered consistent phylogenetic scenarios of jawed vertebrates, such as the paraphyly of placoderms with respect to crown gnathostomes, and antiarchs as the sister group of all other jawed vertebrates. However, some of the phylogenetic relationships within the group have remained controversial, such as the positions of Entelognathus, ptyctodontids, and the Guiyu-lineage that comprises Guiyu, Psarolepis and Achoania. The revision of the dataset in a recent study reveals a modified phylogenetic hypothesis, which shows that some of these phylogenetic conflicts were sourced from a few inadvertent miscodings. The interrelationships of early gnathostomes are addressed based on a combined new dataset with 103 taxa and 335 characters, which is the most comprehensive morphological dataset constructed to date. This dataset is investigated in a phylogenetic context using maximum parsimony (MP), Bayesian inference (BI) and maximum likelihood (ML) approaches in an attempt to explore the consensus and incongruence between the hypotheses of early gnathostome interrelationships recovered from different methods. Our findings consistently corroborate the paraphyly of placoderms, all 'acanthodians' as a paraphyletic stem group of chondrichthyans, Entelognathus as a stem gnathostome, and the Guiyu-lineage as stem sarcopterygians. The incongruence using different methods is less significant than the consensus, and mainly relates to the positions of the placoderm Wuttagoonaspis, the stem chondrichthyan Ramirosuarezia, and the stem osteichthyan Lophosteus-the taxa that are either poorly known or highly specialized in character complement. Given that the different performances of each phylogenetic approach, our study provides an empirical case that the multiple phylogenetic analyses of morphological data are mutually complementary rather than redundant.
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Affiliation(s)
- Tuo Qiao
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
| | - Benedict King
- School of Biological Sciences, Flinders University, Adelaide, South Australia, Australia
| | - John A. Long
- School of Biological Sciences, Flinders University, Adelaide, South Australia, Australia
| | - Per E. Ahlberg
- Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen, Uppsala, Sweden
| | - Min Zhu
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
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Giles S, Darras L, Clément G, Blieck A, Friedman M. An exceptionally preserved Late Devonian actinopterygian provides a new model for primitive cranial anatomy in ray-finned fishes. Proc Biol Sci 2016; 282:20151485. [PMID: 26423841 PMCID: PMC4614771 DOI: 10.1098/rspb.2015.1485] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Actinopterygians (ray-finned fishes) are the most diverse living osteichthyan (bony vertebrate) group, with a rich fossil record. However, details of their earliest history during the middle Palaeozoic (Devonian) ‘Age of Fishes' remains sketchy. This stems from an uneven understanding of anatomy in early actinopterygians, with a few well-known species dominating perceptions of primitive conditions. Here we present an exceptionally preserved ray-finned fish from the Late Devonian (Middle Frasnian, ca 373 Ma) of Pas-de-Calais, northern France. This new genus is represented by a single, three-dimensionally preserved skull. CT scanning reveals the presence of an almost complete braincase along with near-fully articulated mandibular, hyoid and gill arches. The neurocranium differs from the coeval Mimipiscis in displaying a short aortic canal with a distinct posterior notch, long grooves for the lateral dorsal aortae, large vestibular fontanelles and a broad postorbital process. Identification of similar but previously unrecognized features in other Devonian actinopterygians suggests that aspects of braincase anatomy in Mimipiscis are apomorphic, questioning its ubiquity as stand-in for generalized actinopterygian conditions. However, the gill skeleton of the new form broadly corresponds to that of Mimipiscis, and adds to an emerging picture of primitive branchial architecture in crown gnathostomes. The new genus is recovered in a polytomy with Mimiidae and a subset of Devonian and stratigraphically younger actinopterygians, with no support found for a monophyletic grouping of Moythomasia with Mimiidae.
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Affiliation(s)
- Sam Giles
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK
| | - Laurent Darras
- 313 Rue Nationale, Appt. 96, Nœux-les-Mines 62290, France
| | - Gaël Clément
- Centre de Recherches sur la Paléobiodiversité et les Paléoenvironnements (CR2P, UMR 7207), Sorbonne Universités, MNHN, CNRS, UPMC-Paris 6, Muséum National d'Histoire Naturelle, CP 38, 57 Rue Cuvier, 75231 Paris cedex 05, France
| | - Alain Blieck
- Université de Lille-Sciences et technologies, UFR Sciences de la Terre, UMR 8198 'EvoEcoPaleo' du CNRS, Villeneuve d'Ascq cedex 59655, France
| | - Matt Friedman
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK
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45
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Andreev P, Coates MI, Karatajūtė-Talimaa V, Shelton RM, Cooper PR, Wang NZ, Sansom IJ. The systematics of the Mongolepidida (Chondrichthyes) and the Ordovician origins of the clade. PeerJ 2016; 4:e1850. [PMID: 27350896 PMCID: PMC4918221 DOI: 10.7717/peerj.1850] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 03/05/2016] [Indexed: 11/20/2022] Open
Abstract
The Mongolepidida is an Order of putative early chondrichthyan fish, originally erected to unite taxa from the Lower Silurian of Mongolia. The present study reassesses mongolepid systematics through the examination of the developmental, histological and morphological characteristics of scale-based specimens from the Upper Ordovician Harding Sandstone (Colorado, USA) and the Upper Llandovery–Lower Wenlock Yimugantawu (Tarim Basin, China), Xiushan (Guizhou Province, China) and Chargat (north-western Mongolia) Formations. The inclusion of the Mongolepidida within the Class Chondrichthyes is supported on the basis of a suite of scale attributes (areal odontode deposition, linear odontocomplex structure and lack of enamel, cancellous bone and hard-tissue resorption) shared with traditionally recognized chondrichthyans (euchondrichthyans, e.g., ctenacanthiforms). The mongolepid dermal skeleton exhibits a rare type of atubular dentine (lamellin) that is regarded as one of the diagnostic features of the Order within crown gnathostomes. The previously erected Mongolepididae and Shiqianolepidae families are revised, differentiated by scale-base histology and expanded to include the genera Rongolepisand Xinjiangichthys, respectively. A newly described mongolepid species (Solinalepis levis gen. et sp. nov.) from the Ordovician of North America is treated as family incertae sedis, as it possesses a type of basal bone tissue (acellular and vascular) that has yet to be documented in other mongolepids. This study extends the stratigraphic and palaeogeographic range of Mongolepidida and adds further evidence for an early diversification of the Chondrichthyes in the Ordovician Period, 50 million years prior to the first recorded appearance of euchondrichthyan teeth in the Lower Devonian.
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Affiliation(s)
- Plamen Andreev
- School of Geography, Earth and Environmental Sciences, University of Birmingham , Birmingham , United Kingdom
| | - Michael I Coates
- Department of Organismal Biology and Anatomy, University of Chicago , Chicago , United States
| | | | - Richard M Shelton
- School of Dentistry, University of Birmingham , Birmingham , United Kingdom
| | - Paul R Cooper
- School of Dentistry, University of Birmingham , Birmingham , United Kingdom
| | - Nian-Zhong Wang
- Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences , Beijing , China
| | - Ivan J Sansom
- School of Geography, Earth and Environmental Sciences, University of Birmingham , Birmingham , United Kingdom
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46
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Lu J, Giles S, Friedman M, den Blaauwen J, Zhu M. The Oldest Actinopterygian Highlights the Cryptic Early History of the Hyperdiverse Ray-Finned Fishes. Curr Biol 2016; 26:1602-1608. [DOI: 10.1016/j.cub.2016.04.045] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 03/29/2016] [Accepted: 04/18/2016] [Indexed: 10/21/2022]
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47
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Qu Q, Sanchez S, Zhu M, Blom H, Ahlberg PE. The origin of novel features by changes in developmental mechanisms: ontogeny and three-dimensional microanatomy of polyodontode scales of two early osteichthyans. Biol Rev Camb Philos Soc 2016; 92:1189-1212. [DOI: 10.1111/brv.12277] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 03/14/2016] [Accepted: 03/17/2016] [Indexed: 01/25/2023]
Affiliation(s)
- Qingming Qu
- Subdepartment of Evolution and Development, Department of Organismal Biology; Uppsala University; Norbyvägen 18A 75236 Uppsala Sweden
| | - Sophie Sanchez
- European Synchrotron Radiation Facility; 71 avenue des Martyrs F-38043 Grenoble Cedex 09 France
- Subdepartment of Evolution and Development, Department of Organismal Biology, Science For Life Laboratory; Uppsala University; Norbyvägen 18A SE-752 36 Uppsala Sweden
| | - Min Zhu
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences; Xiwaidajie 142 Beijing 100044 China
| | - Henning Blom
- Subdepartment of Evolution and Development, Department of Organismal Biology; Uppsala University; Norbyvägen 18A 75236 Uppsala Sweden
| | - Per Erik Ahlberg
- Subdepartment of Evolution and Development, Department of Organismal Biology, Science For Life Laboratory; Uppsala University; Norbyvägen 18A SE-752 36 Uppsala Sweden
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48
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Dores RM, Liang L, Davis P, Thomas AL, Petko B. 60 YEARS OF POMC: Melanocortin receptors: evolution of ligand selectivity for melanocortin peptides. J Mol Endocrinol 2016; 56:T119-33. [PMID: 26792827 DOI: 10.1530/jme-15-0292] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 01/20/2016] [Indexed: 01/31/2023]
Abstract
The evolution of the melanocortin receptors (MCRs) is linked to the evolution of adrenocorticotrophic hormone (ACTH), the melanocyte-stimulating hormones (MSHs), and their common precursor pro-opiomelanocortin (POMC). The origin of the MCRs and POMC appears to be grounded in the early radiation of the ancestral protochordates. During the genome duplications that have occurred during the evolution of the chordates, the organization plan for POMC was established, and features that have been retained include, the high conservation of the amino acid sequences of α-MSH and ACTH, and the presence of the HFRW MCR activation motif in all of the melanocortin peptides (i.e. ACTH, α-MSH, β-MSH, γ-MSH, and δ-MSH). For the MCRs, the chordate genome duplication events resulted in the proliferation of paralogous receptor genes, and a divergence in ligand selectivity. While most gnathostome MCRs can be activated by either ACTH or the MSHs, teleost and tetrapod MC2R orthologs can only be activated by ACTH. The appearance of the accessory protein, MRAP1, paralleled the emergence of teleost and tetrapods MC2R ligand selectivity, and the dependence of these orthologs on MRAP1 for trafficking to the plasma membrane. The accessory protein, MRAP2, does not affect MC2R ligand selectivity, but does influence the functionality of MC4R orthologs. In this regard, the roles that these accessory proteins may play in the physiology of the five MCRs (i.e. MC1R, MC2R, MC3R, MC4R, and MC5R) are discussed.
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Affiliation(s)
- Robert M Dores
- Department of Biological SciencesUniversity of Denver, Denver, Colorado, USA
| | - Liang Liang
- Department of Biological SciencesUniversity of Denver, Denver, Colorado, USA
| | - Perry Davis
- Department of Biological SciencesUniversity of Denver, Denver, Colorado, USA
| | - Alexa L Thomas
- Department of Biological SciencesUniversity of Denver, Denver, Colorado, USA
| | - Bogdana Petko
- Department of Biological SciencesUniversity of Denver, Denver, Colorado, USA
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49
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Abstract
Theories on the origin of vertebrate teeth have long focused on chondrichthyans as reflecting a primitive condition—but this is better informed by the extinct placoderms, which constitute a sister clade or grade to the living gnathostomes. Here, we show that ‘supragnathal’ toothplates from the acanthothoracid placoderm Romundina stellina comprise multi-cuspid teeth, each composed of an enameloid cap and core of dentine. These were added sequentially, approximately circumferentially, about a pioneer tooth. Teeth are bound to a bony plate that grew with the addition of marginal teeth. Homologous toothplates in arthrodire placoderms exhibit a more ordered arrangement of teeth that lack enameloid, but their organization into a gnathal, bound by layers of cellular bone associated with the addition of each successional tooth, is the same. The presence of enameloid in the teeth of Romundina suggests that it has been lost in other placoderms. Its covariation in the teeth and dermal skeleton of placoderms suggests a lack of independence early in the evolution of jawed vertebrates. It also appears that the dentition—manifest as discrete gnathal ossifications—was developmentally discrete from the jaws during this formative episode of vertebrate evolution.
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Affiliation(s)
- Martin Rücklin
- Naturalis Biodiversity Center, Postbus 9517, 2300 RA Leiden, The Netherlands School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Philip C J Donoghue
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
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50
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Lloyd GT. Estimating morphological diversity and tempo with discrete character-taxon matrices: implementation, challenges, progress, and future directions. Biol J Linn Soc Lond 2016. [DOI: 10.1111/bij.12746] [Citation(s) in RCA: 128] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Graeme T. Lloyd
- Department of Biological Sciences; Faculty of Science; Macquarie University; NSW 2109 Australia
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