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Werneburg I, Preuschoft H. Evolution of the temporal skull openings in land vertebrates: A hypothetical framework on the basis of biomechanics. Anat Rec (Hoboken) 2024; 307:1559-1593. [PMID: 38197580 DOI: 10.1002/ar.25371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 12/04/2023] [Accepted: 12/05/2023] [Indexed: 01/11/2024]
Abstract
The complex constructions of land vertebrate skulls have inspired a number of functional analyses. In the present study, we provide a basic view on skull biomechanics and offer a framework for more general observations using advanced modeling approaches in the future. We concentrate our discussion on the cranial openings in the temporal skull region and work out two major, feeding-related factors that largely influence the shape of the skull. We argue that (1) the place where the most forceful biting is conducted and (2) the handling of resisting food (sideward movements) constitute the formation and shaping of either one or two temporal arcades surrounding these openings. Diversity in temporal skull anatomy among amniotes can be explained by specific modulations of these factors with different amounts of acting forces which inevitably lead to deposition or reduction of bone material. For example, forceful anterior bite favors an infratemporal bar, whereas forceful posterior bite favors formation of an upper temporal arcade. Transverse forces (inertia and resistance of seized objects) as well as neck posture also influence the shaping of the temporal region. Considering their individual skull morphotypes, we finally provide hypotheses on the feeding adaptation in a variety of major tetrapod groups. We did not consider ligaments, internal bone structure, or cranial kinesis in our considerations. Involving those in quantitative tests of our hypotheses, such as finite element system synthesis, will provide a comprehensive picture on cranial mechanics and evolution in the future.
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Affiliation(s)
- Ingmar Werneburg
- Paläontologische Sammlung, Fachbereich Geowissenschaften, Eberhard Karls Universität, Tübingen, Germany
- Senckenberg Center for Human Evolution and Palaeoenvironment, Eberhard Karls Universität, Tübingen, Germany
| | - Holger Preuschoft
- Funktionelle Morphologie im Anatomischen Institut, Ruhr-Universität Bochum, Bochum, Germany
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2
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Pratt CJ, Meili CH, Jones AL, Jackson DK, England EE, Wang Y, Hartson S, Rogers J, Elshahed MS, Youssef NH. Anaerobic fungi in the tortoise alimentary tract illuminate early stages of host-fungal symbiosis and Neocallimastigomycota evolution. Nat Commun 2024; 15:2714. [PMID: 38548766 PMCID: PMC10978972 DOI: 10.1038/s41467-024-47047-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 03/18/2024] [Indexed: 04/01/2024] Open
Abstract
Anaerobic gut fungi (AGF, Neocallimastigomycota) reside in the alimentary tract of herbivores. While their presence in mammals is well documented, evidence for their occurrence in non-mammalian hosts is currently sparse. Culture-independent surveys of AGF in tortoises identified a unique community, with three novel deep-branching genera representing >90% of sequences in most samples. Representatives of all genera were successfully isolated under strict anaerobic conditions. Transcriptomics-enabled phylogenomic and molecular dating analyses indicated an ancient, deep-branching position in the AGF tree for these genera, with an evolutionary divergence time estimate of 104-112 million years ago (Mya). Such estimates push the establishment of animal-Neocallimastigomycota symbiosis from the late to the early Cretaceous. Further, tortoise-associated isolates (T-AGF) exhibited limited capacity for plant polysaccharides metabolism and lacked genes encoding several carbohydrate-active enzyme (CAZyme) families. Finally, we demonstrate that the observed curtailed degradation capacities and reduced CAZyme repertoire is driven by the paucity of horizontal gene transfer (HGT) in T-AGF genomes, compared to their mammalian counterparts. This reduced capacity was reflected in an altered cellulosomal production capacity in T-AGF. Our findings provide insights into the phylogenetic diversity, ecological distribution, evolutionary history, evolution of fungal-host nutritional symbiosis, and dynamics of genes acquisition in Neocallimastigomycota.
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Affiliation(s)
- Carrie J Pratt
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Casey H Meili
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Adrienne L Jones
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Darian K Jackson
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Emma E England
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Yan Wang
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON, Canada
| | - Steve Hartson
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, USA
| | - Janet Rogers
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, USA
| | - Mostafa S Elshahed
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Noha H Youssef
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA.
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3
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Motani R, Pyenson ND. Downsizing a heavyweight: factors and methods that revise weight estimates of the giant fossil whale Perucetus colossus. PeerJ 2024; 12:e16978. [PMID: 38436015 PMCID: PMC10909350 DOI: 10.7717/peerj.16978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 01/29/2024] [Indexed: 03/05/2024] Open
Abstract
Extremes in organismal size have broad interest in ecology and evolution because organismal size dictates many traits of an organism's biology. There is particular fascination with identifying upper size extremes in the largest vertebrates, given the challenges and difficulties of measuring extant and extinct candidates for the largest animal of all time, such as whales, terrestrial non-avian dinosaurs, and extinct marine reptiles. The discovery of Perucetus colossus, a giant basilosaurid whale from the Eocene of Peru, challenged many assumptions about organismal extremes based on reconstructions of its body weight that exceeded reported values for blue whales (Balaenoptera musculus). Here we present an examination of a series of factors and methodological approaches to assess reconstructing body weight in Perucetus, including: data sources from large extant cetaceans; fitting published body mass estimates to body outlines; testing the assumption of isometry between skeletal and body masses, even with extrapolation; examining the role of pachyostosis in body mass reconstructions; addressing method-dependent error rates; and comparing Perucetus with known physiological and ecological limits for living whales, and Eocene oceanic productivity. We conclude that Perucetus did not exceed the body mass of today's blue whales. Depending on assumptions and methods, we estimate that Perucetus weighed 60-70 tons assuming a length 17 m. We calculated larger estimates potentially as much as 98-114 tons at 20 m in length, which is far less than the direct records of blue whale weights, or the 270 ton estimates that we calculated for body weights of the largest blue whales measured by length.
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Affiliation(s)
- Ryosuke Motani
- Department of Earth and Planetary Sciences, University of California, Davis, Davis, California, United States
| | - Nicholas D. Pyenson
- Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, District of Columbia, United States
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Singh SA, Elsler A, Stubbs TL, Rayfield EJ, Benton MJ. Predatory synapsid ecomorphology signals growing dynamism of late Palaeozoic terrestrial ecosystems. Commun Biol 2024; 7:201. [PMID: 38368492 PMCID: PMC10874460 DOI: 10.1038/s42003-024-05879-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 02/01/2024] [Indexed: 02/19/2024] Open
Abstract
Terrestrial ecosystems evolved substantially through the Palaeozoic, especially the Permian, gaining much new complexity, especially among predators. Key among these predators were non-mammalian synapsids. Predator ecomorphology reflect interactions with prey and competitors, which are key controls on carnivore diversity and ecology. Therefore, carnivorous synapsids may offer insight on wider ecological evolution as the first complex, tetrapod-dominated, terrestrial ecosystems formed through the late Palaeozoic. Using morphometric and phylogenetic comparative methods, we chart carnivorous synapsid trophic morphology from the latest Carboniferous to the earliest Triassic (307-251.2 Ma). We find a major morphofunctional shift in synapsid carnivory between the early and middle Permian, via the addition of new feeding modes increasingly specialised for greater biting power or speed that captures the growing antagonism and dynamism of terrestrial tetrapod predator-prey interactions. The further evolution of new hypo- and hypercarnivorous synapsids highlight the nascent intrinsic pressures and complexification of terrestrial ecosystems across the mid-late Permian.
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Affiliation(s)
- Suresh A Singh
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol, BS8 1TQ, UK.
| | - Armin Elsler
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Thomas L Stubbs
- School of Life, Health and Chemical Sciences, Open University, Milton Keynes, MK7 6AE, UK
| | - Emily J Rayfield
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Michael J Benton
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol, BS8 1TQ, UK
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5
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Meili CH, Jones AL, Arreola AX, Habel J, Pratt CJ, Hanafy RA, Wang Y, Yassin AS, TagElDein MA, Moon CD, Janssen PH, Shrestha M, Rajbhandari P, Nagler M, Vinzelj JM, Podmirseg SM, Stajich JE, Goetsch AL, Hayes J, Young D, Fliegerova K, Grilli DJ, Vodička R, Moniello G, Mattiello S, Kashef MT, Nagy YI, Edwards JA, Dagar SS, Foote AP, Youssef NH, Elshahed MS. Patterns and determinants of the global herbivorous mycobiome. Nat Commun 2023; 14:3798. [PMID: 37365172 PMCID: PMC10293281 DOI: 10.1038/s41467-023-39508-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 06/14/2023] [Indexed: 06/28/2023] Open
Abstract
Despite their role in host nutrition, the anaerobic gut fungal (AGF) component of the herbivorous gut microbiome remains poorly characterized. Here, to examine global patterns and determinants of AGF diversity, we generate and analyze an amplicon dataset from 661 fecal samples from 34 mammalian species, 9 families, and 6 continents. We identify 56 novel genera, greatly expanding AGF diversity beyond current estimates (31 genera and candidate genera). Community structure analysis indicates that host phylogenetic affiliation, not domestication status and biogeography, shapes the community rather than. Fungal-host associations are stronger and more specific in hindgut fermenters than in foregut fermenters. Transcriptomics-enabled phylogenomic and molecular clock analyses of 52 strains from 14 genera indicate that most genera with preferences for hindgut hosts evolved earlier (44-58 Mya) than those with preferences for foregut hosts (22-32 Mya). Our results greatly expand the documented scope of AGF diversity and provide an ecologically and evolutionary-grounded model to explain the observed patterns of AGF diversity in extant animal hosts.
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Affiliation(s)
- Casey H Meili
- Oklahoma State University, Department of Microbiology and Molecular Genetics, Stillwater, OK, USA
| | - Adrienne L Jones
- Oklahoma State University, Department of Microbiology and Molecular Genetics, Stillwater, OK, USA
| | - Alex X Arreola
- Oklahoma State University, Department of Microbiology and Molecular Genetics, Stillwater, OK, USA
| | - Jeffrey Habel
- Oklahoma State University, Department of Microbiology and Molecular Genetics, Stillwater, OK, USA
| | - Carrie J Pratt
- Oklahoma State University, Department of Microbiology and Molecular Genetics, Stillwater, OK, USA
| | - Radwa A Hanafy
- Oklahoma State University, Department of Microbiology and Molecular Genetics, Stillwater, OK, USA
| | - Yan Wang
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, ON, Canada
| | - Aymen S Yassin
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Moustafa A TagElDein
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Christina D Moon
- AgResearch Ltd, Grasslands Research Centre, Palmerston North, New Zealand
| | - Peter H Janssen
- AgResearch Ltd, Grasslands Research Centre, Palmerston North, New Zealand
| | - Mitesh Shrestha
- Department of Applied Microbiology and Food Technology, Research Institute for Bioscience and Biotechnology (RIBB), Kathmandu, Nepal
| | - Prajwal Rajbhandari
- Department of Applied Microbiology and Food Technology, Research Institute for Bioscience and Biotechnology (RIBB), Kathmandu, Nepal
| | - Magdalena Nagler
- Universität Innsbruck, Faculty of Biology, Department of Microbiology, Innsbruck, Austria
| | - Julia M Vinzelj
- Universität Innsbruck, Faculty of Biology, Department of Microbiology, Innsbruck, Austria
| | - Sabine M Podmirseg
- Universität Innsbruck, Faculty of Biology, Department of Microbiology, Innsbruck, Austria
| | - Jason E Stajich
- Department of Microbiology and Plant Pathology, University of California, Riverside, Riverside, CA, USA
| | | | | | - Diana Young
- Bavarian State Research Center for Agriculture, Freising, Germany
| | - Katerina Fliegerova
- Institute of Animal Physiology and Genetics Czech Academy of Sciences, Prague, Czechia
| | - Diego Javier Grilli
- Área de Microbiología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | | | - Giuseppe Moniello
- Department of Veterinary Medicine, University of Sassari, Sardinia, Italy
| | - Silvana Mattiello
- University of Milan, Dept. of Agricultural and Environmental Sciences, Milan, Italy
| | - Mona T Kashef
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Yosra I Nagy
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | | | | | - Andrew P Foote
- Oklahoma State University, Department of Animal and Food Sciences, Stillwater, OK, USA
| | - Noha H Youssef
- Oklahoma State University, Department of Microbiology and Molecular Genetics, Stillwater, OK, USA.
| | - Mostafa S Elshahed
- Oklahoma State University, Department of Microbiology and Molecular Genetics, Stillwater, OK, USA.
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6
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Mann A, Henrici AC, Sues HD, Pierce SE. A new Carboniferous edaphosaurid and the origin of herbivory in mammal forerunners. Sci Rep 2023; 13:4459. [PMID: 37019927 PMCID: PMC10076360 DOI: 10.1038/s41598-023-30626-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 02/27/2023] [Indexed: 04/07/2023] Open
Abstract
Herbivory evolved independently in several tetrapod lineages during the Late Carboniferous and became more widespread throughout the Permian Period, eventually leading to the basic structure of modern terrestrial ecosystems. Here we report a new taxon of edaphosaurid synapsid based on two fossils recovered from the Moscovian-age cannel coal of Linton, Ohio, which we interpret as an omnivore-low-fibre herbivore. Melanedaphodon hovaneci gen. et sp. nov. provides the earliest record of an edaphosaurid to date and is one of the oldest known synapsids. Using high-resolution X-ray micro-computed tomography, we provide a comprehensive description of the new taxon that reveals similarities between Late Carboniferous and early Permian (Cisuralian) members of Edaphosauridae. The presence of large bulbous, cusped, marginal teeth alongside a moderately-developed palatal battery, distinguishes Melanedaphodon from all other known species of Edaphosauridae and suggests adaptations for processing tough plant material already appeared among the earliest synapsids. Furthermore, we propose that durophagy may have provided an early pathway to exploit plant resources in terrestrial ecosystems.
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Affiliation(s)
- Arjan Mann
- Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, MRC 121, P.O. Box 37012, Washington, DC, 20013-7012, USA.
| | - Amy C Henrici
- Section of Vertebrate Paleontology, Carnegie Museum of Natural History, 4400 Forbes Avenue, Pittsburgh, PA, 15213, USA
| | - Hans-Dieter Sues
- Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, MRC 121, P.O. Box 37012, Washington, DC, 20013-7012, USA
| | - Stephanie E Pierce
- Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
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7
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Kapsetaki SE, Marquez Alcaraz G, Maley CC, Whisner CM, Aktipis A. Diet, Microbes, and Cancer Across the Tree of Life: a Systematic Review. Curr Nutr Rep 2022; 11:508-525. [PMID: 35704266 PMCID: PMC9197725 DOI: 10.1007/s13668-022-00420-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/21/2022] [Indexed: 11/09/2022]
Abstract
PURPOSE OF REVIEW Cancers are a leading cause of death in humans and for many other species. Diet has often been associated with cancers, and the microbiome is an essential mediator between diet and cancers. Here, we review the work on cancer and the microbiome across species to search for broad patterns of susceptibility associated with different microbial species. RECENT FINDINGS Some microbes, such as Helicobacter bacteria, papillomaviruses, and the carnivore-associated Fusobacteria, consistently induce tumorigenesis in humans and other species. Other microbes, such as the milk-associated Lactobacillus, consistently inhibit tumorigenesis in humans and other species. We systematically reviewed over a thousand published articles and identified links between diet, microbes, and cancers in several species of mammals, birds, and flies. Future work should examine a larger variety of host species to discover new model organisms for human preclinical trials, to better understand the observed variance in cancer prevalence across species, and to discover which microbes and diets are associated with cancers across species. Ultimately, this could help identify microbial and dietary interventions to diagnose, prevent, and treat cancers in humans as well as other animals.
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Affiliation(s)
- Stefania E Kapsetaki
- Arizona Cancer Evolution Center, Biodesign Institute and School of Life Sciences, Arizona State University, Tempe, AZ, USA.
- Biodesign Center for Biocomputing, Security and Society, Arizona State University, Tempe, USA.
| | - Gissel Marquez Alcaraz
- Arizona Cancer Evolution Center, Biodesign Institute and School of Life Sciences, Arizona State University, Tempe, AZ, USA
- Biodesign Center for Biocomputing, Security and Society, Arizona State University, Tempe, USA
| | - Carlo C Maley
- Arizona Cancer Evolution Center, Biodesign Institute and School of Life Sciences, Arizona State University, Tempe, AZ, USA
- Biodesign Center for Biocomputing, Security and Society, Arizona State University, Tempe, USA
| | - Corrie M Whisner
- College of Health Solutions, Arizona State University, Phoenix, AZ, USA
- Biodesign Center for Health Through Microbiomes, Arizona State University, Tempe, AZ, USA
| | - Athena Aktipis
- Arizona Cancer Evolution Center, Biodesign Institute and School of Life Sciences, Arizona State University, Tempe, AZ, USA
- Department of Psychology, Arizona State University, Tempe, AZ, USA
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8
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Buatois LA, Davies NS, Gibling MR, Krapovickas V, Labandeira CC, MacNaughton RB, Mángano MG, Minter NJ, Shillito AP. The Invasion of the Land in Deep Time: Integrating Paleozoic Records of Paleobiology, Ichnology, Sedimentology, and Geomorphology. Integr Comp Biol 2022; 62:297-331. [PMID: 35640908 DOI: 10.1093/icb/icac059] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 04/19/2022] [Accepted: 05/24/2022] [Indexed: 11/13/2022] Open
Abstract
The invasion of the land was a complex, protracted process, punctuated by mass extinctions, that involved multiple routes from marine environments. We integrate paleobiology, ichnology, sedimentology, and geomorphology to reconstruct Paleozoic terrestrialization. Cambrian landscapes were dominated by laterally mobile rivers with unstable banks in the absence of significant vegetation. Temporary incursions by arthropods and worm-like organisms into coastal environments apparently did not result in establishment of continental communities. Contemporaneous lacustrine faunas may have been inhibited by limited nutrient delivery and high sediment loads. The Ordovician appearance of early land plants triggered a shift in the primary locus of the global clay mineral factory, increasing the amount of mudrock on the continents. The Silurian-Devonian rise of vascular land plants, including the first forests and extensive root systems, was instrumental in further retaining fine sediment on alluvial plains. These innovations led to increased architectural complexity of braided and meandering rivers. Landscape changes were synchronous with establishment of freshwater and terrestrial arthropod faunas in overbank areas, abandoned fluvial channels, lake margins, ephemeral lakes, and inland deserts. Silurian-Devonian lakes experienced improved nutrient availability, due to increased phosphate weathering and terrestrial humic matter. All these changes favoured frequent invasions to permament establishment of jawless and jawed fishes in freshwater habitats and the subsequent tetrapod colonization of the land. The Carboniferous saw rapid diversification of tetrapods, mostly linked to aquatic reproduction, and land plants, including gymnosperms. Deeper root systems promoted further riverbank stabilization, contributing to the rise of anabranching rivers and braided systems with vegetated islands. New lineages of aquatic insects developed and expanded novel feeding modes, including herbivory. Late Paleozoic soils commonly contain pervasive root and millipede traces. Lacustrine animal communities diversified, accompanied by increased food-web complexity and improved food delivery which may have favored permanent colonization of offshore and deep-water lake environments. These trends continued in the Permian, but progressive aridification favored formation of hypersaline lakes, which were stressful for colonization. The Capitanian and end-Permian extinctions affected lacustrine and fluvial biotas, particularly the invertebrate infauna, although burrowing may have allowed some tetrapods to survive associated global warming and increased aridification.
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Affiliation(s)
- Luis A Buatois
- Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada
| | - Neil S Davies
- Department of Earth Sciences, University of Cambridge, Cambridge, Cambridgeshire CB2 3EQ, UK
| | - Martin R Gibling
- Department of Earth and Environmental Sciences, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Verónica Krapovickas
- Departamento de Ciencias Geológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria, C1428EGA, Argentina
| | - Conrad C Labandeira
- Department of Paleobiology, Smithsonian Institution, Washington DC 20013-7012, USA.,Department of Entomology and BEES Program, University of Maryland, College Park, Maryland 21740, USA.,College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Robert B MacNaughton
- Geological Survey of Canada (Calgary), Natural Resources Canada, Calgary, Alberta T2L 2A7, Canada
| | - M Gabriela Mángano
- Department of Geological Sciences, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E2, Canada
| | - Nicholas J Minter
- School of the Environment, Geography, and Geosciences, University of Portsmouth, Portsmouth, Hampshire PO1 3QL, UK
| | - Anthony P Shillito
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, UK
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9
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Abel P, Pommery Y, Ford DP, Koyabu D, Werneburg I. Skull Sutures and Cranial Mechanics in the Permian Reptile Captorhinus aguti and the Evolution of the Temporal Region in Early Amniotes. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.841784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
While most early limbed vertebrates possessed a fully-roofed dermatocranium in their temporal skull region, temporal fenestrae and excavations evolved independently at least twice in the earliest amniotes, with several different variations in shape and position of the openings. Yet, the specific drivers behind this evolution have been only barely understood. It has been mostly explained by adaptations of the feeding apparatus as a response to new functional demands in the terrestrial realm, including a rearrangement of the jaw musculature as well as changes in strain distribution. Temporal fenestrae have been retained in most extant amniotes but have also been lost again, notably in turtles. However, even turtles do not represent an optimal analog for the condition in the ancestral amniote, highlighting the necessity to examine Paleozoic fossil material. Here, we describe in detail the sutures in the dermatocranium of the Permian reptile Captorhinus aguti (Amniota, Captorhinidae) to illustrate bone integrity in an early non-fenestrated amniote skull. We reconstruct the jaw adductor musculature and discuss its relation to intracranial articulations and bone flexibility within the temporal region. Lastly, we examine whether the reconstructed cranial mechanics in C. aguti could be treated as a model for the ancestor of fenestrated amniotes. We show that C. aguti likely exhibited a reduced loading in the areas at the intersection of jugal, squamosal, and postorbital, as well as at the contact between parietal and postorbital. We argue that these “weak” areas are prone for the development of temporal openings and may be treated as the possible precursors for infratemporal and supratemporal fenestrae in early amniotes. These findings provide a good basis for future studies on other non-fenestrated taxa close to the amniote base, for example diadectomorphs or other non-diapsid reptiles.
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10
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Jenkins KM, Bhullar BAS. Tooth Implantation and Attachment in Scoloparia glyphanodon (Parareptilia: Procolophonidae). Bulletin of the Peabody Museum of Natural History 2022. [DOI: 10.3374/014.063.0103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Kelsey M. Jenkins
- Department of Earth and Planetary Sciences, Yale University, New Haven, CT 06520-8109 USA —
| | - Bhart-Anjan S. Bhullar
- Department of Earth and Planetary Sciences, Yale University, New Haven, CT 06520-8109 USA; and Peabody Museum of Natural History, Yale University, New Haven, CT 06520-8118 USA
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11
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Brocklehurst N, Ford DP, Benson RBJ. Early origins of divergent patterns of morphological evolution on the mammal and reptile stem-lineages. Syst Biol 2022; 71:1195-1209. [PMID: 35274702 PMCID: PMC9366456 DOI: 10.1093/sysbio/syac020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 02/09/2022] [Accepted: 03/05/2022] [Indexed: 11/28/2022] Open
Abstract
The origin of amniotes 320 million years ago signaled independence from water in vertebrates and was closely followed by divergences within the mammal and reptile stem lineages (Synapsida and Reptilia). Early members of both groups had highly similar morphologies, being superficially “lizard-like” forms with many plesiomorphies. However, the extent to which they might have exhibited divergent patterns of evolutionary change, with the potential to explain the large biological differences between their living members, is unresolved. We use a new, comprehensive phylogenetic dataset to quantify variation in rates and constraints of morphological evolution among Carboniferous–early Permian amniotes. We find evidence for an early burst of evolutionary rates, resulting in the early origins of morphologically distinctive subgroups that mostly persisted through the Cisuralian. Rates declined substantially through time, especially in reptiles. Early reptile evolution was also more constrained compared with early synapsids, exploring a more limited character state space. Postcranial innovation in particular was important in early synapsids, potentially related to their early origins of large body size. In contrast, early reptiles predominantly varied the temporal region, suggesting disparity in skull and jaw kinematics, and foreshadowing the variability of cranial biomechanics seen in reptiles today. Our results demonstrate that synapsids and reptiles underwent an early divergence of macroevolutionary patterns. This laid the foundation for subsequent evolutionary events and may be critical in understanding the substantial differences between mammals and reptiles today. Potential explanations include an early divergence of developmental processes or of ecological factors, warranting cross-disciplinary investigation. [Amniote; body size; constraint; phylogeny; rate.]
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Affiliation(s)
- Neil Brocklehurst
- Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, UK
| | - David P Ford
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, UK
| | - Roger B J Benson
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, UK
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12
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Werneburg I, Abel P. Modeling Skull Network Integrity at the Dawn of Amniote Diversification With Considerations on Functional Morphology and Fossil Jaw Muscle Reconstructions. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2021.799637] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
One of the major questions in evolutionary vertebrate morphology is the origin and meaning of temporal skull openings in land vertebrates. Partly or fully surrounded by bones, one, two, or even three openings may evolve behind the orbit, within the ancestrally fully roofed anapsid (scutal) skull. At least ten different morphotypes can be distinguished in tetrapods with many modifications and transitions in more crownward representatives. A number of potential factors driving the emergence and differentiation of temporal openings have been proposed in the literature, but only today are proper analytical tools available to conduct traceable tests for the functional morphology underlying temporal skull constructions. In the present study, we examined the anatomical network in the skull of one representative of early amniotes, †Captorhinus aguti, which ancestrally exhibits an anapsid skull. The resulting skull modularity revealed a complex partitioning of the temporal region indicating, in its intersections, the candidate positions for potential infratemporal openings. The framework of †C. aguti was then taken as a template to model a series of potential temporal skull morphotypes in order to understand how skull openings might influence the modular composition of the amniote skull in general. We show that the original pattern of skull modularity (†C. aguti) experiences comprehensive changes by introducing one or two temporal openings in different combinations and in different places. The resulting modules in each skull model are interpreted in regard to the feeding behavior of amniotes that exhibit(ed) the respective skull morphotypes. An important finding is the alternative incorporation of the jugal and palate to different modules enforcing the importance of an integrated view on skull evolution: the temporal region cannot be understood without considering palatal anatomy. Finally, we discuss how to better reconstruct relative jaw muscle compositions in fossils by considering the modularity of the skull network. These considerations might be relevant for future biomechanical studies on skull evolution.
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13
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Song J, Zheng H, Xue J, Liu J, Sun Q, Yang W, Liu F, Xiang X, He K, Chen Y, Cheng J, Li W, Jin J, Brosius J, Deng C. GPR15-C10ORF99 functional pairing initiates colonic Treg homing in amniotes. EMBO Rep 2021; 23:e53246. [PMID: 34939731 PMCID: PMC8892231 DOI: 10.15252/embr.202153246] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 10/29/2021] [Accepted: 12/06/2021] [Indexed: 02/05/2023] Open
Abstract
Regulatory T lymphocyte (Treg) homing reactions mediated by G protein‐coupled receptor (GPCR)–ligand interactions play a central role in maintaining intestinal immune homeostasis by restraining inappropriate immune responses in the gastrointestinal tract. However, the origin of Treg homing to the colon remains mysterious. Here, we report that the C10ORF99 peptide (also known as CPR15L and AP57), a cognate ligand of GPR15 that controls Treg homing to the colon, originates from a duplication of the flanking CDHR1 gene and is functionally paired with GPR15 in amniotes. Evolutionary analysis and experimental data indicate that the GPR15–C10ORF99 pair is functionally conserved to mediate colonic Treg homing in amniotes and their expression patterns are positively correlated with herbivore diet in the colon. With the first herbivorous diet in early amniotes, a new biological process (herbivorous diet short‐chain fatty acid‐C10ORF99/GPR15‐induced Treg homing colon immune homeostasis) emerged, and we propose an evolutionary model whereby GPR15–C10ORF99 functional pairing has initiated the first colonic Treg homing reaction in amniotes. Our findings also highlight that GPCR–ligand pairing leads to physiological adaptation during vertebrate evolution.
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Affiliation(s)
- Jingjing Song
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China.,Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Huaping Zheng
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Jingwen Xue
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Jian Liu
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Qian Sun
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Wei Yang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Fang Liu
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Xiangyin Xiang
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Kai He
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, and Guangdong Provincial Key Laboratory of Single Cell Technology and Application, Southern Medical University, Guangzhou, China
| | - Younan Chen
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Jingqiu Cheng
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Wei Li
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Jin Jin
- MOE Laboratory of Biosystem Homeostasis and Protection, and Life Sciences Institute, Zhejiang University, Hangzhou, China
| | - Juergen Brosius
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China
| | - Cheng Deng
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu, China.,Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
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14
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Zhao X, Yu Y, Clapham ME, Yan E, Chen J, Jarzembowski EA, Zhao X, Wang B. Early evolution of beetles regulated by the end-Permian deforestation. eLife 2021; 10:72692. [PMID: 34747694 PMCID: PMC8585485 DOI: 10.7554/elife.72692] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 11/03/2021] [Indexed: 01/10/2023] Open
Abstract
The end-Permian mass extinction (EPME) led to a severe terrestrial ecosystem collapse. However, the ecological response of insects—the most diverse group of organisms on Earth—to the EPME remains poorly understood. Here, we analyse beetle evolutionary history based on taxonomic diversity, morphological disparity, phylogeny, and ecological shifts from the Early Permian to Middle Triassic, using a comprehensive new dataset. Permian beetles were dominated by xylophagous stem groups with high diversity and disparity, which probably played an underappreciated role in the Permian carbon cycle. Our suite of analyses shows that Permian xylophagous beetles suffered a severe extinction during the EPME largely due to the collapse of forest ecosystems, resulting in an Early Triassic gap of xylophagous beetles. New xylophagous beetles appeared widely in the early Middle Triassic, which is consistent with the restoration of forest ecosystems. Our results highlight the ecological significance of insects in deep-time terrestrial ecosystems.
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Affiliation(s)
- Xianye Zhao
- State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yilun Yu
- University of Chinese Academy of Sciences, Beijing, China.,Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China
| | - Matthew E Clapham
- Department of Earth and Planetary Sciences, University of California, Santa Cruz, Santa Cruz, United States
| | - Evgeny Yan
- Palaeontological Institute, Russian Academy of Sciences, Moscow, Russian Federation
| | - Jun Chen
- State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing, China.,Institute of Geology and Paleontology, Linyi University, Linyi, China
| | - Edmund A Jarzembowski
- State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing, China.,Department of Earth Sciences, Natural History Museum, London, United Kingdom
| | - Xiangdong Zhao
- State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Bo Wang
- State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing, China
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15
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Brocklehurst N, Benson RJ. Multiple paths to morphological diversification during the origin of amniotes. Nat Ecol Evol 2021; 5:1243-9. [PMID: 34312521 DOI: 10.1038/s41559-021-01516-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 06/11/2021] [Indexed: 02/06/2023]
Abstract
Early terrestrial vertebrates (amniotes) provide a classic example of diversification following adaptive zone invasion. The initial terrestrialization of vertebrates was closely followed by dietary diversification, as evidenced by a proliferation of craniomandibular and dental adaptations. However, morphological evolution of early amniotes has received limited study, in analyses with restricted taxonomic scope, leaving substantial questions about the dynamics of this important terrestrial radiation. We use novel analyses of discrete characters to quantify variation in evolutionary rates and constraints during diversification of the amniote feeding apparatus. We find evidence for an early burst, comprising high rates of anatomical change that decelerated through time, giving way to a background of saturated morphological evolution. Subsequent expansions of phenotypic diversity were not associated with increased evolutionary rates. Instead, variation in the mode of evolution became important, with groups representing independent origins of herbivory evolving distinctive, group-specific morphologies and thereby exploring novel character-state spaces. Our findings indicate the importance of plant-animal interactions in structuring the earliest radiation of amniotes and demonstrate the importance of variation in modes of phenotypic divergence during a major evolutionary radiation.
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16
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Mann A, Calthorpe AS, Maddin HC. Joermungandr bolti, an exceptionally preserved 'microsaur' from the Mazon Creek Lagerstätte reveals patterns of integumentary evolution in Recumbirostra. R Soc Open Sci 2021; 8:210319. [PMID: 34295525 PMCID: PMC8292758 DOI: 10.1098/rsos.210319] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 06/24/2021] [Indexed: 05/14/2023]
Abstract
The Carboniferous Pennsylvanian-aged (309-307 Ma) Mazon Creek Lagerstätte produces some of the earliest fossils of major Palaeozoic tetrapod lineages. Recently, several new tetrapod specimens collected from Mazon Creek have come to light, including the earliest fossorially adapted recumbirostrans. Here, we describe a new long-bodied recumbirostran, Joermungandr bolti gen. et sp. nov., known from a single part and counterpart concretion bearing a virtually complete skeleton. Uniquely, Joermungandr preserves a full suite of dorsal, flank and ventral dermal scales, together with a series of thinned and reduced gastralia. Investigation of these scales using scanning electron microscopy reveals ultrastructural ridge and pit morphologies, revealing complexities comparable to the scale ultrastructure of extant snakes and fossorial reptiles, which have scales modified for body-based propulsion and shedding substrate. Our new taxon also represents an important early record of an elongate recumbirostran bauplan, wherein several features linked to fossoriality, including a characteristic recumbent snout, are present. We used parsimony phylogenetic methods to conduct phylogenetic analysis using the most recent recumbirostran-focused matrix. The analysis recovers Joermungandr within Recumbirostra with likely affinities to the sister clades Molgophidae and Brachystelechidae. Finally, we review integumentary patterns in Recumbirostra, noting reductions and losses of gastralia and osteoderms associated with body elongation and, thus, probably also associated with increased fossoriality.
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Affiliation(s)
- Arjan Mann
- Department of Earth Sciences, Carleton University, 2115 Herzberg Laboratories,1125 Colonel By Drive, Ottawa, Ontario, Canada K1S 5B6
| | - Ami S. Calthorpe
- Department of Earth Sciences, Carleton University, 2115 Herzberg Laboratories,1125 Colonel By Drive, Ottawa, Ontario, Canada K1S 5B6
| | - Hillary C. Maddin
- Department of Earth Sciences, Carleton University, 2115 Herzberg Laboratories,1125 Colonel By Drive, Ottawa, Ontario, Canada K1S 5B6
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17
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Singh SA, Elsler A, Stubbs TL, Bond R, Rayfield EJ, Benton MJ. Niche partitioning shaped herbivore macroevolution through the early Mesozoic. Nat Commun 2021; 12:2796. [PMID: 33990610 PMCID: PMC8121902 DOI: 10.1038/s41467-021-23169-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 04/16/2021] [Indexed: 02/04/2023] Open
Abstract
The Triassic (252-201 Ma) marks a major punctuation in Earth history, when ecosystems rebuilt themselves following the devastating Permian-Triassic mass extinction. Herbivory evolved independently several times as ecosystems comprising diverse assemblages of therapsids, parareptiles and archosauromorphs rose and fell, leading to a world dominated by dinosaurs. It was assumed that dinosaurs prevailed either through long-term competitive replacement of the incumbent clades or rapidly and opportunistically following one or more extinction events. Here we use functional morphology and ecology to explore herbivore morphospace through the Triassic and Early Jurassic. We identify five main herbivore guilds (ingestion generalists, prehension specialists, durophagous specialists, shearing pulpers, and heavy oral processors), and find that herbivore clades generally avoided competition by almost exclusively occupying different guilds. Major ecosystem remodelling was triggered multiple times by external environmental challenges, and previously dominant herbivores were marginalised by newly emerging forms. Dinosaur dominance was a mix of opportunity following disaster, combined with competitive advantage in their new world.
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Affiliation(s)
- Suresh A Singh
- School of Earth Sciences, University of Bristol, Bristol, UK.
| | - Armin Elsler
- School of Earth Sciences, University of Bristol, Bristol, UK
| | - Thomas L Stubbs
- School of Earth Sciences, University of Bristol, Bristol, UK
| | - Russell Bond
- School of Earth Sciences, University of Bristol, Bristol, UK
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18
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Brocklehurst N, Kammerer CF, Benson RJ. The origin of tetrapod herbivory: effects on local plant diversity. Proc Biol Sci 2020; 287:20200124. [PMID: 32517628 PMCID: PMC7341937 DOI: 10.1098/rspb.2020.0124] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 05/12/2020] [Indexed: 11/12/2022] Open
Abstract
The origin of herbivory in the Carboniferous was a landmark event in the evolution of terrestrial ecosystems, increasing ecological diversity in animals but also giving them greater influence on the evolution of land plants. We evaluate the effect of early vertebrate herbivory on plant evolution by comparing local species richness of plant palaeofloras with that of vertebrate herbivores and herbivore body size. Vertebrate herbivores became diverse and achieved a much greater range of body sizes across the Carboniferous-Permian transition interval. This coincides with an abrupt reduction in local plant richness that persists throughout the Permian. Time-series regression analysis supports a negative relationship of plant richness with herbivore richness but a positive relationship of plant richness with minimum herbivore body size. This is consistent with studies of present-day ecosystems in which increased diversity of smaller, more selective herbivores places greater predation pressures on plants, while a prevalence of larger bodied, less selective herbivores reduces the dominance of a few highly tolerant plant species, thereby promoting greater local richness. The diversification of herbivores across the Carboniferous-Permian boundary, along with the appearance of smaller, more selective herbivores like bolosaurid parareptiles, constrained plant diversity throughout the Permian. These findings demonstrate that the establishment of widespread vertebrate herbivory has structured plant communities since the late Palaeozoic, as expected from examination of modern ecosystems, and illustrates the potential for fossil datasets in testing palaeoecological hypotheses.
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Affiliation(s)
- Neil Brocklehurst
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, UK
| | | | - Roger J. Benson
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, UK
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19
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Snyder AJ, LeBlanc ARH, Jun C, Bevitt JJ, Reisz RR. Thecodont tooth attachment and replacement in bolosaurid parareptiles. PeerJ 2020; 8:e9168. [PMID: 32440377 PMCID: PMC7229766 DOI: 10.7717/peerj.9168] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 04/20/2020] [Indexed: 11/20/2022] Open
Abstract
Permian bolosaurid parareptiles are well-known for having complex tooth crowns and complete tooth rows in the jaws, in contrast to the comparatively simple teeth and frequent replacement gaps in all other Paleozoic amniotes. Analysis of the specialized dentition of the bolosaurid parareptiles Bolosaurus from North America and Belebey from Russia, utilizing a combination of histological and tomographic data, reveals unusual patterns of tooth development and replacement. The data confirm that bolosaurid teeth have thecodont implantation with deep roots, the oldest known such example among amniotes, and independently evolved among much younger archosauromorphs (including dinosaurs and crocodilians) and among synapsids (including mammals). High-resolution CT scans were able to detect the density boundary between the alveolar bone and the jawbone, as confirmed by histology, and revealed the location and size of developing replacement teeth in the pulp cavity of functional teeth. Evidence provided by the paratype dentary of Belebey chengi indicates that replacement teeth are present along the whole tooth row at slightly different stages of development, with the ontogenetically more developed teeth anteriorly, suggesting that tooth replacement was highly synchronized. CT data also show tooth replacement is directly related to the presence of lingual pits in the jaw, and that migration of tooth buds occurs initially close to these resorption pits to a position immediately below the functional tooth within its pulp cavity. The size and complex shape of the replacement teeth in the holotype of Bolosaurus grandis indicate that the replacement teeth can develop within the pulp cavity to an advanced stage while the previous generation remains functional for an extended time, reminiscent of the condition seen in other amniotes with occluding dentitions, including mammals.
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Affiliation(s)
- Adam J Snyder
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada
| | - Aaron R H LeBlanc
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Chen Jun
- International Center of Future Science, Dinosaur Evolution Research Center, Jilin University, Changchun, China.,Lab for Evolution of Past Life and Environment in Northeast Asia, Jilin University, Ministry of Education, Changchun, China
| | | | - Robert R Reisz
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada.,International Center of Future Science, Dinosaur Evolution Research Center, Jilin University, Changchun, China
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20
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Katz O. Silicon and Plant-Animal Interactions: Towards an Evolutionary Framework. Plants (Basel) 2020; 9:E430. [PMID: 32244583 DOI: 10.3390/plants9040430] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 03/19/2020] [Accepted: 03/20/2020] [Indexed: 12/16/2022]
Abstract
Herbivory is fundamental in ecology, being a major driver of ecosystem structure and functioning. Plant Si and phytoliths play a significant antiherbivory role, the understanding of which and of its evolutionary context will increase our understanding of this phenomenon, its origins, and its significance for past, extant, and future ecosystems. To achieve this goal, we need a superdisciplinary evolutionary framework connecting the role of Si in plant–herbivore interactions, in global processes, and in plant and herbivore evolution. To do this properly, we should acknowledge and incorporate into our work some basic facts that are too often overlooked. First, there is great taxonomic variance both in plant Si contents, forms, and roles, but also in herbivore responses, dietary preferences, and in fossil evidence. Second, species and their traits, as well as whole ecosystems, should be seen in the context of their entire evolutionary history and may therefore reflect not only adaptations to extant selective factors but also anachronistic traits. Third, evolutionary history and evolutionary transitions are complex, resulting in true and apparent asynchronisms. Fourth, evolution and ecology are multiscalar, in which various phenomena and processes act at various scales. Taking these issues into consideration will improve our ability to develop this needed theoretical framework and will bring us closer to gaining a more complete understanding of one of the most exciting and elusive phenomena in plant biology and ecology.
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21
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Cisneros JC, Angielczyk K, Kammerer CF, Smith RM, Fröbisch J, Marsicano CA, Richter M. Captorhinid reptiles from the lower Permian Pedra de Fogo Formation, Piauí, Brazil: the earliest herbivorous tetrapods in Gondwana. PeerJ 2020; 8:e8719. [PMID: 32185112 PMCID: PMC7061909 DOI: 10.7717/peerj.8719] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 02/10/2020] [Indexed: 11/20/2022] Open
Abstract
The Pedra de Fogo Formation in the Parnaíba Basin of northeastern Brazil hosts a recently discovered lacustrine fauna and provides the only known record of the Captorhinidae in South America. Here, new captorhinid remains from this unit are described. Two partial mandibles, including one formerly ascribed to the genus Captorhinus, are here referred to Captorhinikos sp. a genus previously described from North America. The natural mould of a large mandible probably represents a new taxon within the captorhinid subclade Moradisaurinae, and a small skull roof is regarded as Captorhinidae indet. Captorhinids are generally considered to have been herbivores or omnivores. The Pedra de Fogo captorhinids likely played an important ecological role as primary consumers in the palaeoenvironment of this geological unit, which is also known for its extensive record of petrified forests. The new finds reinforce the close relationships between the continental faunas of palaeotropical western Gondwana and palaeoequatorial North America during the Cisuralian.
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Affiliation(s)
- Juan C. Cisneros
- Museu de Arqueologia e Paleontologia, Universidade Federal do Piauí, Teresina, Piauí, Brazil
| | - Kenneth Angielczyk
- Negaunee Integrative Research Center, Field Museum of Natural History, Chicago, IL, USA
| | | | - Roger M.H. Smith
- Department of Karoo Palaeontology, Iziko South African Museum, Cape Town, Western Cape, South Africa
- Evolutionary Studies Institute, University of Witwatersrand, Johannesburg, Gauteng, South Africa
| | - Jörg Fröbisch
- Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Berlin, Germany
- Institut für Biologie, Humboldt Universität Berlin, Berlin, Germany
| | - Claudia A. Marsicano
- Departamento de Ciencias Geológicas, FCEN, IDEAN-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Martha Richter
- Earth Sciences Department, Natural History Museum, London, UK
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22
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Benson RBJ, Barrett PM. Evolution: The Two Faces of Plant-Eating Dinosaurs. Curr Biol 2020; 30:R14-R16. [PMID: 31910368 DOI: 10.1016/j.cub.2019.11.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Plant-eating dinosaurs evolved varied feeding strategies. A new study demonstrates convergent evolution of their skulls and teeth towards two distinct functional optima, one resembling advanced mammalian herbivory and the other echoing herbivory in birds and other reptiles.
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Affiliation(s)
- Roger B J Benson
- Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK.
| | - Paul M Barrett
- Department of Earth Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, UK
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23
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Ford DP, Benson RBJ. The phylogeny of early amniotes and the affinities of Parareptilia and Varanopidae. Nat Ecol Evol 2019; 4:57-65. [DOI: 10.1038/s41559-019-1047-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 10/22/2019] [Indexed: 12/12/2022]
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Whitney MR, Sidor CA. Histological and developmental insights into the herbivorous dentition of tapinocephalid therapsids. PLoS One 2019; 14:e0223860. [PMID: 31665173 PMCID: PMC6821052 DOI: 10.1371/journal.pone.0223860] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 09/30/2019] [Indexed: 11/23/2022] Open
Abstract
Tapinocephalids were one of the earliest therapsid clades to evolve herbivory. In acquiring derived tooth-to-tooth occlusion by means of an exaggerated heel and talon crown morphology, members of this family have long been considered herbivorous, yet little work has been done to describe their dentition. Given the early occurrence of this clade and their acquisition of a dentition with several derived features, tapinocephalids serve as an important clade in understanding adaptations to herbivory as well as macroevolutionary patterns of dental trait acquisition. Here we describe the histology of tapinocephalid jaws and incisors to assess adaptations to herbivory. Our results yield new dental characters for tapinocephalids including a peculiar enamel structure and reduced enamel deposition on the occlusal surface. These traits are convergent with other specialized herbivorous dentitions like those found in ornithischian dinosaurs and ungulates. Furthermore, these results demonstrate that while acquiring some specializations, tapinocephalids also retained plesiomorphic traits like alternate, continuous replacement. We interpret these findings as an example of how different combinations of traits can facilitate a derived and specialized dentition and then discuss their implications in the acquisition of a mammal-like dentition.
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Affiliation(s)
- Megan. R. Whitney
- Department of Biology and Burke Museum, University of Washington, Seattle, Washington, United States of America
- * E-mail:
| | - Christian A. Sidor
- Department of Biology and Burke Museum, University of Washington, Seattle, Washington, United States of America
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Maho S, Gee BM, Reisz RR. A new varanopid synapsid from the early Permian of Oklahoma and the evolutionary stasis in this clade. R Soc Open Sci 2019; 6:191297. [PMID: 31824730 PMCID: PMC6837192 DOI: 10.1098/rsos.191297] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 09/24/2019] [Indexed: 06/10/2023]
Abstract
Varanopids are a basal clade of small- to medium-sized non-therapsid synapsids, whose range extends from the late Pennsylvanian to the late middle Permian, and are found in North America, Russia, Europe and South Africa. The greatest varanopid diversity is observed at the fossiliferous cave deposits near Richards Spur, Oklahoma, well known for the preservation of a complex early Permian upland community. Two previously described varanopids, Mycterosaurus and Varanops, are known only from fragmentary disarticulated material at Richards Spur. A third putative varanopid, Basicranodon fortsillensis, represented by a partial parasphenoid, has been synonymized with Mycterosaurus longiceps. This study reports on a new varanopid taxon, represented by substantially more complete material, including three nearly complete skulls. Such comprehensive cranial material allows for a detailed study of the taxon and its relationship to other varanopids. This new varanopid bears great morphological similarity to Mesenosaurus romeri from the middle Permian Mezen River Basin of northern Russia. Phylogenetic analysis recovers a sister relationship between this taxon and Me. romeri. This relationship, in conjunction with a detailed morphological comparison, supports the placement of this taxon within Mesenosaurus, as a new species, Me. efremovi. These results reveal an unexpected extension of the geographical and temporal range of Mesenosaurus, contributing to our understanding of varanopid dispersal. The extended persistence of this basal clade of predatory synapsids, underscored by the apparent evolutionary stasis of this genus, is unusual among Palaeozoic tetrapods. This phenomenon implies an exceptionally high degree of extended ecological resilience across major faunal and environmental transitions.
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Affiliation(s)
- Sigi Maho
- Department of Biology, University of Toronto at Mississauga, 3359 Mississauga Road, Mississauga, Ontario, CanadaL5L 1C6
| | - Bryan M. Gee
- Department of Biology, University of Toronto at Mississauga, 3359 Mississauga Road, Mississauga, Ontario, CanadaL5L 1C6
| | - Robert R. Reisz
- International Centre of Future Science, Jilin University, 2699 Qianjin Avenue, Changchun, Jilin Province, People's Republic of China
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Gilbert SF. Developmental symbiosis facilitates the multiple origins of herbivory. Evol Dev 2019; 22:154-164. [PMID: 31332951 DOI: 10.1111/ede.12291] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/22/2019] [Accepted: 02/28/2019] [Indexed: 01/05/2023]
Abstract
Developmental bias toward particular evolutionary trajectories can be facilitated through symbiosis. Organisms are holobionts, consisting of zygote-derived cells and a consortia of microbes, and the development, physiology, and immunity of animals are properties of complex interactions between the zygote-derived cells and microbial symbionts. Such symbionts can be agents of developmental plasticity, allowing an organism to develop in particular directions. This plasticity can lead to genetic assimilation either through the incorporation of microbial genes into host genomes or through the direct maternal transmission of the microbes. Such plasticity can lead to niche construction, enabling the microbes to remodel host anatomy and/or physiology. In this article, I will focus on the ability of symbionts to bias development toward the evolution of herbivory. I will posit that the behavioral and morphological manifestations of herbivorous phenotypes must be preceded by the successful establishment of a community of symbiotic microbes that can digest cell walls and detoxify plant poisons. The ability of holobionts to digest plant materials can range from being a plastic trait, dependent on the transient incorporation of environmental microbes, to becoming a heritable trait of the holobiont organism, transmitted through the maternal propagation of symbionts or their genes.
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Affiliation(s)
- Scott F Gilbert
- Department of Biology, Swarthmore College, Swarthmore, Pennsylvania
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Abstract
AbstractThe Carboniferous (Pennsylvanian; 309–307 Mya) ‘Mazon Creek’ Lagerstätte produces some of the earliest tetrapod fossils of major Palaeozoic lineages. Previously, the Mazon Creek record of ‘microsaurs’ was known from a single specimen. However, the lack of key anatomy, such as the skull, precluded a confident taxonomic assignment, thus only a suggested affinity to the microbrachimorph ‘microsaur’ Hyloplesion was determined. Recently several new tetrapod specimens collected from Mazon Creek have come to light, of which some have recumbirostran ‘microsaur’ affinity. Here we describe a new genus and species of short-bodied recumbirostran, Diabloroter bolti, on the basis of a unique combination of autapomorphies. Both parsimony and Bayesian phylogenetic methods recover the new taxon in the Brachystelechidae clade, as sister to a clade including Carrolla and Batropetes. We determine Diabloroter to be the earliest known member of Brachytelechidae and thus establishing a Carboniferous origin of the family. We also provide an updated diagnosis for Brachystelechidae. Finally, we comment on the evolutionary trends in the clade, including dental adaptations for a proposed algivorous diet in derived clade members.
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Affiliation(s)
- Arjan Mann
- Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada
| | - Hillary C Maddin
- Department of Earth Sciences, Carleton University, Ottawa, Ontario, Canada
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Clack JA, Ruta M, Milner AR, Marshall JEA, Smithson TR, Smithson KZ. Acherontiscus caledoniae: the earliest heterodont and durophagous tetrapod. R Soc Open Sci 2019; 6:182087. [PMID: 31218034 PMCID: PMC6549999 DOI: 10.1098/rsos.182087] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 04/01/2019] [Indexed: 06/09/2023]
Abstract
The enigmatic tetrapod Acherontiscus caledoniae from the Pendleian stage of the Early Carboniferous shows heterodontous and durophagous teeth, representing the earliest known examples of significant adaptations in tetrapod dental morphology. Tetrapods of the Late Devonian and Early Carboniferous (Mississippian), now known in some depth, are generally conservative in their dentition and body morphologies. Their teeth are simple and uniform, being cone-like and sometimes recurved at the tip. Modifications such as keels occur for the first time in Early Carboniferous Tournaisian tetrapods. Acherontiscus, dated as from the Pendleian stage, is notable for being very small with a skull length of about 15 mm, having an elongate vertebral column and being limbless. Cladistic analysis places it close to the Early Carboniferous adelospondyls, aïstopods and colosteids and supports the hypothesis of 'lepospondyl' polyphyly. Heterodonty is associated with a varied diet in tetrapods, while durophagy suggests a diet that includes hard tissue such as chitin or shells. The mid-Carboniferous saw a significant increase in morphological innovation among tetrapods, with an expanded diversity of body forms, skull shapes and dentitions appearing for the first time.
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Affiliation(s)
| | - Marcello Ruta
- School of Life Sciences, University of Lincoln, Joseph Banks Laboratories, Green Lane, Lincoln LN6 7DL, UK
| | - Andrew R. Milner
- Department of Earth Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, UK
| | - John E. A. Marshall
- School of Ocean and Earth Science, National Oceanography Centre, University of Southampton, Waterfront Campus, European Way, Southampton SO14 3ZH, UK
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Abstract
Mammals and their closest fossil relatives use their shoulders and forelimbs for many functions, which is reflected by the great range of mammalian forelimb shapes. We found that forelimb shape diversity in the early mammalian lineage (Synapsida) began to increase about 270 million years ago, with the emergence of a group called Therapsida, and is accompanied by new forelimb functions. The functional diversification of therapsid forelimbs was curtailed by the Permo-Triassic mass extinction, but eventually continued as more mammal-like therapsids evolved new ecologies. Our analyses characterize the deep time origin of a quintessential part of the mammalian body plan: evolutionarily labile forelimbs that can be deployed in a wide range of functional and ecological roles. Mammals and their closest fossil relatives are unique among tetrapods in expressing a high degree of pectoral girdle and forelimb functional diversity associated with fully pelagic, cursorial, subterranean, volant, and other lifestyles. However, the earliest members of the mammalian stem lineage, the “pelycosaur”-grade synapsids, present a far more limited range of morphologies and inferred functions. The more crownward nonmammaliaform therapsids display novel forelimb morphologies that have been linked to expanded functional diversity, suggesting that the roots of this quintessentially mammalian phenotype can be traced to the pelycosaur–therapsid transition in the Permian period. We quantified morphological disparity of the humerus in pelycosaur-grade synapsids and therapsids using geometric morphometrics. We found that disparity begins to increase concurrently with the emergence of Therapsida, and that it continues to rise until the Permo-Triassic mass extinction. Further, therapsid exploration of new regions of morphospace is correlated with the evolution of novel ecomorphologies, some of which are characterized by changes to overall limb morphology. This evolutionary pattern confirms that nonmammaliaform therapsid forelimbs underwent ecomorphological diversification throughout the Permian, with functional elaboration initially being more strongly expressed in the proximal end of the humerus than the distal end. The role of the forelimbs in the functional diversification of therapsids foreshadows the deployment of forelimb morphofunctional diversity in the evolutionary radiation of mammals.
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Ware IM, Fitzpatrick CR, Senthilnathan A, Bayliss SLJ, Beals KK, Mueller LO, Summers JL, Wooliver RC, Van Nuland ME, Kinnison MT, Palkovacs EP, Schweitzer JA, Bailey JK. Feedbacks link ecosystem ecology and evolution across spatial and temporal scales: Empirical evidence and future directions. Funct Ecol 2019. [DOI: 10.1111/1365-2435.13267] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Ian M. Ware
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee
| | | | | | - Shannon L. J. Bayliss
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee
| | - Kendall K. Beals
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee
| | - Liam O. Mueller
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee
| | - Jennifer L. Summers
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee
| | - Rachel C. Wooliver
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee
| | | | | | - Eric P. Palkovacs
- Department of Ecology and Evolutionary Biology University of California Santa Cruz California
| | - Jennifer A. Schweitzer
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee
| | - Joseph K. Bailey
- Department of Ecology and Evolutionary Biology University of Tennessee Knoxville Tennessee
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Jones KE, Angielczyk KD, Polly PD, Head JJ, Fernandez V, Lungmus JK, Tulga S, Pierce SE. Fossils reveal the complex evolutionary history of the mammalian regionalized spine. Science 2018; 361:1249-1252. [DOI: 10.1126/science.aar3126] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 04/27/2018] [Accepted: 07/25/2018] [Indexed: 11/02/2022]
Affiliation(s)
- K. E. Jones
- Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - K. D. Angielczyk
- Integrative Research Center, Field Museum of Natural History, Chicago, IL 60605, USA
| | - P. D. Polly
- Department of Earth and Atmospheric Sciences, Indiana University, Bloomington, IN 47405, USA
| | - J. J. Head
- Department of Zoology and University Museum of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - V. Fernandez
- European Synchrotron Radiation Facility, 38000 Grenoble, France
| | - J. K. Lungmus
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637, USA
| | - S. Tulga
- Department of Geophysical Sciences, University of Chicago, Chicago, IL 60637, USA
| | - S. E. Pierce
- Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
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Buchwitz M, Voigt S. On the morphological variability of Ichniotherium tracks and evolution of locomotion in the sistergroup of amniotes. PeerJ 2018; 6:e4346. [PMID: 29404225 PMCID: PMC5797465 DOI: 10.7717/peerj.4346] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 01/19/2018] [Indexed: 11/20/2022] Open
Abstract
Ichniotherium tracks with a relatively short pedal digit V (digit length ratio V/IV < 0.6) form the majority of yet described Late Carboniferous to Early Permian diadectomorph tracks and can be related to a certain diadectid clade with corresponding phalangeal reduction that includes Diadectes and its close relatives. Here we document the variation of digit proportions and trackway parameters in 25 trackways (69 step cycles) from nine localities and seven further specimens with incomplete step cycles from the type locality of Ichniotherium cottae (Gottlob quarry) in order to find out whether this type of Ichniotherium tracks represents a homogeneous group or an assemblage of distinct morphotypes and includes variability indicative for evolutionary change in trackmaker locomotion. According to our results, the largest sample of tracks from three Lower Permian sites of the Thuringian Forest, commonly referred to I. cottae, is not homogeneous but shows a clear distinction in pace length, pace angulation, apparent trunk length and toe proportions between tracks from Bromacker quarry and those from the stratigraphically older sites Birkheide and Gottlob quarry. Three Late Carboniferous trackways of Ichniotherium with relatively short pedal digit V from Haine’s Farm, Ohio, and Alveley near Birmingham, United Kingdom, that have been referred to the ichnotaxa “Baropus hainesi,” “Megabaropus hainesi” and “Ichniotherium willsi,” respectively, share a marked outward rotation of foot imprints with respect to walking direction. Apart from this feature they are in many aspects similar to the Birkheide and Gottlob records of I. cottae. With the possible exception of the Maroon Formation (Early Permian, Colorado) sample, Early Permian Ichniotherium trackways with a relatively short pedal digit V fall into the morphological spectrum of the three well defined “Hainesi–Willsi,” “Birkheide–Gottlob” and “Bromacker” morphotypes. With their more obtuse pace angulations and higher body-size-normalized pace and stride lengths the Bromacker type tracks imply higher walking speeds of their trackmakers compared to all other Ichniotherium tracks. More generally, a trend towards higher locomotion capability from the last common ancestor of all Ichniotherium producers to the last common ancestor of all “Ichniotherium with relatively short pedal digit V” and from the latter to the trackmakers of the mid-Early Permian Bromacker type can be deduced—with the reservation that overall sample size is relatively small, making this scenario a preliminary assessment. Whether the presumed advancements represent a more general pattern within diadectomorphs remains open until the non-European Ichniotherium trackway record improves. Ichnotaxonomic implications are discussed.
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Katz O. Extending the scope of Darwin's 'abominable mystery': integrative approaches to understanding angiosperm origins and species richness. Ann Bot 2018; 121:1-8. [PMID: 29040393 PMCID: PMC5786222 DOI: 10.1093/aob/mcx109] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 08/09/2017] [Indexed: 05/04/2023]
Abstract
Background and aims Angiosperms are the most species-rich group of land plants, but their origins and fast and intense diversification still require an explanation. Scope Extending research scopes can broaden theoretical frameworks and lines of evidence that can lead to solving this 'abominable mystery'. Solutions lie in understanding evolutionary trends across taxa and throughout the Phanerozoic, and integration between hypotheses and ideas that are derived from multiple disciplines. Key Findings Descriptions of evolutionary chronologies should integrate between molecular phylogenies, descriptive palaeontology and palaeoecology. New molecular chronologies open new avenues of research of possible Palaeozoic angiosperm ancestors and how they evolved during as many as 200Myr until the emergence of true angiosperms. The idea that 'biodiversity creates biodiversity' requires evidence from past and present ecologies, with changes in herbivory and resource availability throughout the Phanerozoic appearing to be particularly promising. Conclusions Promoting our understanding of angiosperm origins and diversification in particular, and the evolution of biodiversity in general, requires more profound understanding of the ecological past through integrating taxonomic, temporal and ecological scopes.
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Affiliation(s)
- Ofir Katz
- Department of Geography and Environmental Development, Ben-Gurion University of the Negev, Be’er-Sheva, Israel
- The Dead Sea and Arava Science Center, Mt Massada, Tamar Regional Council, Israel
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35
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Brink KS, Chen YC, Wu YN, Liu WM, Shieh DB, Huang TD, Sun CK, Reisz RR. Dietary adaptions in the ultrastructure of dinosaur dentine. J R Soc Interface 2017; 13:rsif.2016.0626. [PMID: 27974573 DOI: 10.1098/rsif.2016.0626] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Accepted: 11/17/2016] [Indexed: 02/01/2023] Open
Abstract
Teeth are key to understanding the feeding ecology of both extant and extinct vertebrates. Recent studies have highlighted the previously unrecognized complexity of dinosaur dentitions and how specific tooth tissues and tooth shapes differ between taxa with different diets. However, it is unknown how the ultrastructure of these tooth tissues contributes to the differences in feeding style between taxa. In this study, we use third harmonic generation microscopy and scanning electron microscopy to examine the ultrastructure of the dentine in herbivorous and carnivorous dinosaurs to understand how the structure of this tissue contributes to the overall utility of the tooth. Morphometric analyses of dentinal tubule diameter, density and branching rates reveal a strong signal for dietary preferences, with herbivorous saurischian and ornithischian dinosaurs consistently having higher dentinal tubule density than their carnivorous relatives. We hypothesize that this relates to the hardness of the dentine, where herbivorous taxa have dentine that is more resistant to breakage and wear at the dentine-enamel junction than carnivorous taxa. This study advocates the detailed study of dentine and the use of advanced microscopy techniques to understand the evolution of dentition and feeding ecology in extinct vertebrates.
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Affiliation(s)
- Kirstin S Brink
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada L5 L 1C6
| | - Yu-Cheng Chen
- Molecular Imaging Center, National Taiwan University, Taipei 10617, Taiwan, Republic of China
| | - Ya-Na Wu
- Institute of Oral Medicine, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan, Republic of China
| | - Wei-Min Liu
- Department of Electrical Engineering and Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 10617, Taiwan, Republic of China
| | - Dar-Bin Shieh
- Institute of Oral Medicine, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan, Republic of China
| | - Timothy D Huang
- Dinosaur Evolution Research Center, Jilin University, Changchun, Jilin Province 130012, People's Republic of China.,National Chung Hsing University, Taichung 402, Taiwan, Republic of China
| | - Chi-Kuang Sun
- Molecular Imaging Center, National Taiwan University, Taipei 10617, Taiwan, Republic of China.,Department of Electrical Engineering and Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 10617, Taiwan, Republic of China.,Graduate Institute of Biomedical Electronics and Bioinformatics and Center for Optoelectronic Medicine, National Taiwan University, Taipei 10617, Taiwan, Republic of China.,Institute of Physics and Research Center for Applied Sciences, Academia Sinica, Taipei 115, Taiwan, Republic of China
| | - Robert R Reisz
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada L5 L 1C6.,Dinosaur Evolution Research Center, Jilin University, Changchun, Jilin Province 130012, People's Republic of China.,National Chung Hsing University, Taichung 402, Taiwan, Republic of China.,Department of Optics and Photonics, National Central University, Jhongli, Taoyuan 32001, Taiwan, Republic of China
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Abstract
Body size is one of the most important characteristics of an organism, impacting a great variety of ecological characteristics. The influence of diet on body size has received considerable attention, with previous studies suggesting a greater tendency towards increased body size in herbivores than macro-carnivores. The earliest known herbivorous and macro-carnivorous synapsids provide an ideal case study for examining body size evolution in different dietary regimes. Sphenacomorpha contains two lineages: Edaphosauridae (some of the most abundant terrestrial herbivores in the late Carboniferous and early Permian), and Sphenacodontia (the largest and most abundant carnivores of that time). Phylogenetic comparative analyses are used to compare trait evolution in sphenacomorphs, including a Bayesian method for identifying branches along which phenotypic selection occurred. Two branches show rapid increases in body size in the late Carboniferous. The first occurred in Edaphosauridae, along the branch leading to the herbivorous members. The later shift towards larger size occurred in Sphenacodontia, producing a clade of large carnivores. It is possible that the rapid appearance of large herbivorous synapsids in the Carboniferous provided the selective pressure for carnivores to increase their size. Following these two shifts, rates of evolution in edaphosaurids slowed significantly, but the carnivorous sphenacodontians showed further increases.
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Affiliation(s)
- Neil Brocklehurst
- Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstraße 43, D-10115 Berlin, Germany
| | - Kirstin S. Brink
- Department of Oral Health Sciences, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada
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Brocklehurst N. Rates of morphological evolution in Captorhinidae: an adaptive radiation of Permian herbivores. PeerJ 2017; 5:e3200. [PMID: 28417061 PMCID: PMC5392250 DOI: 10.7717/peerj.3200] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 03/18/2017] [Indexed: 11/20/2022] Open
Abstract
The evolution of herbivory in early tetrapods was crucial in the establishment of terrestrial ecosystems, although it is so far unclear what effect this innovation had on the macro-evolutionary patterns observed within this clade. The clades that entered this under-filled region of ecospace might be expected to have experienced an "adaptive radiation": an increase in rates of morphological evolution and speciation driven by the evolution of a key innovation. However such inferences are often circumstantial, being based on the coincidence of a rate shift with the origin of an evolutionary novelty. The conclusion of an adaptive radiation may be made more robust by examining the pattern of the evolutionary shift; if the evolutionary innovation coincides not only with a shift in rates of morphological evolution, but specifically in the morphological characteristics relevant to the ecological shift of interest, then one may more plausibly infer a causal relationship between the two. Here I examine the impact of diet evolution on rates of morphological change in one of the earliest tetrapod clades to evolve high-fibre herbivory: Captorhinidae. Using a method of calculating heterogeneity in rates of discrete character change across a phylogeny, it is shown that a significant increase in rates of evolution coincides with the transition to herbivory in captorhinids. The herbivorous captorhinids also exhibit greater morphological disparity than their faunivorous relatives, indicating more rapid exploration of new regions of morphospace. As well as an increase in rates of evolution, there is a shift in the regions of the skeleton undergoing the most change; the character changes in the herbivorous lineages are concentrated in the mandible and dentition. The fact that the increase in rates of evolution coincides with increased change in characters relating to food acquisition provides stronger evidence for a causal relationship between the herbivorous diet and the radiation event.
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Affiliation(s)
- Neil Brocklehurst
- Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Berlin, Germany
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Clauss M, Nurutdinova I, Meloro C, Gunga HC, Jiang D, Koller J, Herkner B, Sander PM, Hellwich O. Reconstruction of body cavity volume in terrestrial tetrapods. J Anat 2016; 230:325-336. [PMID: 27813090 DOI: 10.1111/joa.12557] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/22/2016] [Indexed: 11/29/2022] Open
Abstract
Although it is generally assumed that herbivores have more voluminous body cavities due to larger digestive tracts required for the digestion of plant fiber, this concept has not been addressed quantitatively. We estimated the volume of the torso in 126 terrestrial tetrapods (synapsids including basal synapsids and mammals, and diapsids including birds, non-avian dinosaurs and reptiles) classified as either herbivore or carnivore in digital models of mounted skeletons, using the convex hull method. The difference in relative torso volume between diet types was significant in mammals, where relative torso volumes of herbivores were about twice as large as that of carnivores, supporting the general hypothesis. However, this effect was not evident in diapsids. This may either reflect the difficulty to reliably reconstruct mounted skeletons in non-avian dinosaurs, or a fundamental difference in the bauplan of different groups of tetrapods, for example due to differences in respiratory anatomy. Evidently, the condition in mammals should not be automatically assumed in other, including more basal, tetrapod lineages. In both synapsids and diapsids, large animals showed a high degree of divergence with respect to the proportion of their convex hull directly supported by bone, with animals like elephants or Triceratops having a low proportion, and animals such as rhinoceros having a high proportion of bony support. The relevance of this difference remains to be further investigated.
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Affiliation(s)
- Marcus Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, University of Zurich, Zurich, Switzerland
| | - Irina Nurutdinova
- Computer Vision and Remote Sensing, Technical University Berlin, Berlin, Germany
| | - Carlo Meloro
- Research Centre in Evolutionary Anthropology and Palaeoecology, Liverpool John Moores University, Liverpool, UK
| | | | - Duofang Jiang
- Computer Vision and Remote Sensing, Technical University Berlin, Berlin, Germany
| | - Johannes Koller
- Computer Vision and Remote Sensing, Technical University Berlin, Berlin, Germany
| | - Bernd Herkner
- Senckenberg Research Institute and Natural History Museum, Frankfurt (Main), Germany
| | - P Martin Sander
- Steinmann Institute of Palaeontology, University of Bonn, Bonn, Germany
| | - Olaf Hellwich
- Computer Vision and Remote Sensing, Technical University Berlin, Berlin, Germany
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Bernardi M, Angielczyk KD, Mitchell JS, Ruta M. Phylogenetic Stability, Tree Shape, and Character Compatibility: A Case Study Using Early Tetrapods. Syst Biol 2016; 65:737-58. [PMID: 27288479 DOI: 10.1093/sysbio/syw049] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Accepted: 05/19/2016] [Indexed: 11/13/2022] Open
Abstract
Phylogenetic tree shape varies as the evolutionary processes affecting a clade change over time. In this study, we examined an empirical phylogeny of fossil tetrapods during several time intervals, and studied how temporal constraints manifested in patterns of tree imbalance and character change. The results indicate that the impact of temporal constraints on tree shape is minimal and highlights the stability through time of the reference tetrapod phylogeny. Unexpected values of imbalance for Mississippian and Pennsylvanian time slices strongly support the hypothesis that the Carboniferous was a period of explosive tetrapod radiation. Several significant diversification shifts take place in the Mississippian and underpin increased terrestrialization among the earliest limbed vertebrates. Character incompatibility is relatively high at the beginning of tetrapod history, but quickly decreases to a relatively stable lower level, relative to a null distribution based on constant rates of character change. This implies that basal tetrapods had high, but declining, rates of homoplasy early in their evolutionary history, although the origin of Lissamphibia is an exception to this trend. The time slice approach is a powerful method of phylogenetic analysis and a useful tool for assessing the impact of combining extinct and extant taxa in phylogenetic analyses of large and speciose clades.
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Affiliation(s)
- Massimo Bernardi
- MUSE-Museo delle Scienze, Corso del Lavoro e della Scienza, 3, 38122 Trento, Italy; School of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol BS8 1RJ, UK;
| | - Kenneth D Angielczyk
- Integrative Research Center, Field Museum of Natural History, 1400 South Lake Shore Drive, Chicago, IL 60605-2496, USA
| | - Jonathan S Mitchell
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48103, USA; and
| | - Marcello Ruta
- School of Life Sciences, Joseph Banks Laboratories, University of Lincoln, Green Lane, Lincoln LN6 7DL, UK
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Brocklehurst N, Ruta M, Müller J, Fröbisch J. Elevated Extinction Rates as a Trigger for Diversification Rate Shifts: Early Amniotes as a Case Study. Sci Rep 2015; 5:17104. [PMID: 26592209 DOI: 10.1038/srep17104] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 10/26/2015] [Indexed: 11/08/2022] Open
Abstract
Tree shape analyses are frequently used to infer the location of shifts in diversification rate within the Tree of Life. Many studies have supported a causal relationship between shifts and temporally coincident events such as the evolution of “key innovations”. However, the evidence for such relationships is circumstantial. We investigated patterns of diversification during the early evolution of Amniota from the Carboniferous to the Triassic, subjecting a new supertree to analyses of tree balance in order to infer the timing and location of diversification shifts. We investigated how uneven origination and extinction rates drive diversification shifts, and use two case studies (herbivory and an aquatic lifestyle) to examine whether shifts tend to be contemporaneous with evolutionary novelties. Shifts within amniotes tend to occur during periods of elevated extinction, with mass extinctions coinciding with numerous and larger shifts. Diversification shifts occurring in clades that possess evolutionary innovations do not coincide temporally with the appearance of those innovations, but are instead deferred to periods of high extinction rate. We suggest such innovations did not cause increases in the rate of cladogenesis, but allowed clades to survive extinction events. We highlight the importance of examining general patterns of diversification before interpreting specific shifts.
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Cisneros JC, Abdala F, Jashashvili T, de Oliveira Bueno A, Dentzien-Dias P. Tiarajudens eccentricus and Anomocephalus africanus, two bizarre anomodonts (Synapsida, Therapsida) with dental occlusion from the Permian of Gondwana. R Soc Open Sci 2015; 2:150090. [PMID: 26587266 PMCID: PMC4632579 DOI: 10.1098/rsos.150090] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 06/16/2015] [Indexed: 06/05/2023]
Abstract
Anomodontia was a highly successful tetrapod clade during the Permian and the Triassic. New morphological information regarding two bizarre basal anomodonts is provided and their palaeoecological significance is explored. The osteology of the recently discovered Tiarajudens eccentricus Cisneros et al. 2011, from the Brazilian Permian, is described in detail. The taxon exhibits unusual postcranial features, including the presence of gastralia. Additional preparation and computed tomography scans of the holotype of Anomocephalus africanus Modesto et al. 1999 discovered in the Karoo Basin of South Africa allow a reappraisal of this genus. Anomocephalus is similar to Tiarajudens with regard to several traits, including a battery of large, transversally expanded, palatal teeth. Molariform teeth are present in the mandible of the African taxon, providing additional insight into the function of the earliest tooth-occlusion mechanism known in therapsids. At least two waves of tooth replacement can be recognized in the palate of Anomocephalus. The outsized, blade-like caniniforms of the herbivorous Tiarajudens allow several non-exclusive ecological interpretations, among which we favour intraspecific display or combat. This behaviour was an alternative to the head-butting practised by the contemporary dinocephalians. Combat specializations that are considered typical of Cenozoic herbivores likely evolved during the Middle Permian, at the time the first communities with diverse, abundant tetrapod herbivores were being assembled.
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Affiliation(s)
| | - Fernando Abdala
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
| | - Tea Jashashvili
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
| | - Ana de Oliveira Bueno
- Departamento de Paleontologia e Estratigrafia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Paula Dentzien-Dias
- Laboratório de Paleontologia e Paleoceanografia, Universidade Federal do Rio Grande, Rio Grande, Brazil
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Brown CM, VanBuren CS, Larson DW, Brink KS, Campione NE, Vavrek MJ, Evans DC. Tooth counts through growth in diapsid reptiles: implications for interpreting individual and size-related variation in the fossil record. J Anat 2015; 226:322-33. [PMID: 25689039 PMCID: PMC4386932 DOI: 10.1111/joa.12280] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/05/2015] [Indexed: 10/24/2022] Open
Abstract
Tooth counts are commonly recorded in fossil diapsid reptiles and have been used for taxonomic and phylogenetic purposes under the assumption that differences in the number of teeth are largely explained by interspecific variation. Although phylogeny is almost certainly one of the greatest factors influencing tooth count, the relative role of intraspecific variation is difficult, and often impossible, to test in the fossil record given the sample sizes available to palaeontologists and, as such, is best investigated using extant models. Intraspecific variation (largely manifested as size-related or ontogenetic variation) in tooth counts has been examined in extant squamates (lizards and snakes) but is poorly understood in archosaurs (crocodylians and dinosaurs). Here, we document tooth count variation in two species of extant crocodylians (Alligator mississippiensis and Crocodylus porosus) as well as a large varanid lizard (Varanus komodoensis). We test the hypothesis that variation in tooth count is driven primarily by growth and thus predict significant correlations between tooth count and size, as well as differences in the frequency of deviation from the modal tooth count in the premaxilla, maxilla, and dentary. In addition to tooth counts, we also document tooth allometry in each species and compare these results with tooth count change through growth. Results reveal no correlation of tooth count with size in any element of any species examined here, with the exception of the premaxilla of C. porosus, which shows the loss of one tooth position. Based on the taxa examined here, we reject the hypothesis, as it is evident that variation in tooth count is not always significantly correlated with growth. However, growth trajectories of smaller reptilian taxa show increases in tooth counts and, although current samples are small, suggest potential correlates between tooth count trajectories and adult size. Nevertheless, interspecific variation in growth patterns underscores the importance of considering and understanding growth when constructing taxonomic and phylogenetic characters, in particular for fossil taxa where ontogenetic patterns are difficult to reconstruct.
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Affiliation(s)
| | | | - Derek W Larson
- Department of Ecology and Evolutionary Biology, University of TorontoToronto, ON, Canada
| | - Kirstin S Brink
- Department of Ecology and Evolutionary Biology, University of TorontoToronto, ON, Canada
| | - Nicolás E Campione
- Palaeobiology Programme, Department of Earth Sciences, Uppsala UniversityUppsala, Sweden
- Subdepartment of Evolution and Development, Department of Organismal Biology, Uppsala UniversityUppsala, Sweden
| | - Matthew J Vavrek
- Department of Natural History, Royal Ontario MuseumToronto, ON, Canada
| | - David C Evans
- Department of Ecology and Evolutionary Biology, University of TorontoToronto, ON, Canada
- Department of Natural History, Royal Ontario MuseumToronto, ON, Canada
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Gibson SZ. Evidence of a specialized feeding niche in a Late Triassic ray-finned fish: evolution of multidenticulate teeth and benthic scraping in †Hemicalypterus. Naturwissenschaften 2015; 102:10. [PMID: 25686871 DOI: 10.1007/s00114-015-1262-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 02/02/2015] [Accepted: 02/04/2015] [Indexed: 10/23/2022]
Abstract
Fishes have evolved to exploit multiple ecological niches. Extant fishes in both marine (e.g., rabbitfishes, surgeonfishes) and freshwater systems (e.g., haplochromine cichlids, characiforms) have evolved specialized, scoop-like, multidenticulate teeth for benthic scraping, feeding primarily on algae. Here, I report evidence of the oldest example of specialized multidenticulate dentition in a ray-finned fish, †Hemicalypterus weiri, from the Upper Triassic Chinle Formation of southeastern Utah (∼210-205 Ma), USA. †H. weiri is a lower actinopterygian species that is phylogenetically remote from modern fishes, and has evolved specialized teeth that converge with those of several living teleost fishes (e.g., characiforms, cichlids, acanthurids, siganids), with a likely function of these teeth being to scrape algae off a rock substrate. This finding contradicts previously held notions that fishes with multicuspid, scoop-like dentition were restricted to teleosts, and indicates that ray-finned fishes were diversifying into different trophic niches and exploring different modes of feeding earlier in their history than previously thought, fundamentally altering our perceptions of the ecological roles of fishes during the Mesozoic.
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Affiliation(s)
- Sarah Z Gibson
- Department of Geology and Biodiversity Institute, University of Kansas, 1345 Jayhawk Boulevard, Lawrence, KS, 66045, USA,
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44
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LeBlanc ARH, Reisz RR. New postcranial material of the early caseid Casea broilii Williston, 1910 (Synapsida: Caseidae) with a review of the evolution of the sacrum in Paleozoic non-mammalian synapsids. PLoS One 2014; 9:e115734. [PMID: 25545624 PMCID: PMC4278720 DOI: 10.1371/journal.pone.0115734] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 12/01/2014] [Indexed: 11/19/2022] Open
Abstract
Here we use the description of a new specimen of the small caseid synapsid Casea broilii that preserves the sacral, pelvic and hind limb regions in great detail and in three dimensions, as a unique opportunity to reevaluate the early stages in the evolution of the sacrum in the lineage that led to mammals. We place this new material in the context of sacral evolution in early caseid synapsids and conclude that the transition from two to three sacral vertebrae occurred in small-bodied species, suggesting that it was not an adaptation to heavy weight bearing. Furthermore, we compare descriptions of sacral anatomy among known early synapsids, including caseids, ophiacodontids, edaphosaurids, varanopids, and sphenacodontians and review sacral evolution in early synapsids. Based on the descriptions of new species of caseids, edaphosaurids, and varanopids over the past several decades, it is clear that a sacrum consisting of three vertebrae evolved independently at least four times in synapsids during the Late Carboniferous and Early Permian. Furthermore, similarities in the morphologies of the sacral vertebrae and ribs of these early synapsids lead us to conclude that an anterior caudal vertebra had been incorporated into the sacral series convergently in these groups. Given the repeated acquisition of a three-vertebra sacrum in early synapsids and no apparent link to body size, we argue that this sacral anatomy was related to more efficient terrestrial locomotion than to increased weight bearing.
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Affiliation(s)
- Aaron R. H. LeBlanc
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada
- * E-mail:
| | - Robert R. Reisz
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada
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45
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Reisz RR, Fröbisch J. The oldest caseid synapsid from the Late Pennsylvanian of Kansas, and the evolution of herbivory in terrestrial vertebrates. PLoS One 2014; 9:e94518. [PMID: 24739998 PMCID: PMC3989228 DOI: 10.1371/journal.pone.0094518] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 02/03/2014] [Indexed: 11/19/2022] Open
Abstract
The origin and early evolution of amniotes (fully terrestrial vertebrates) led to major changes in the structure and hierarchy of terrestrial ecosystems. The first appearance of herbivores played a pivotal role in this transformation. After an early bifurcation into Reptilia and Synapsida (including mammals) 315 Ma, synapsids dominated Paleozoic terrestrial vertebrate communities, with the herbivorous caseids representing the largest vertebrates on land. Eocasea martini gen. et sp. nov., a small carnivorous caseid from the Late Carboniferous, extends significantly the fossil record of Caseidae, and permits the first clade-based study of the origin and initial evolution of herbivory in terrestrial tetrapods. Our results demonstrate for the first time that large caseid herbivores evolved from small, non-herbivorous caseids. This pattern is mirrored by three other clades, documenting multiple, independent, but temporally staggered origins of herbivory and increase in body size among early terrestrial tetrapods, leading to patterns consistent with modern terrestrial ecosystem.
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Affiliation(s)
- Robert R. Reisz
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada
- * E-mail:
| | - Jörg Fröbisch
- Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Berlin, Germany
- Institut für Biologie, Humboldt-Universität zu Berlin, Berlin, Germany
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46
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Clements KD, Angert ER, Montgomery WL, Choat JH. Intestinal microbiota in fishes: what's known and what's not. Mol Ecol 2014; 23:1891-8. [PMID: 24612310 DOI: 10.1111/mec.12699] [Citation(s) in RCA: 143] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 01/29/2014] [Accepted: 02/16/2014] [Indexed: 12/21/2022]
Abstract
High-throughput sequencing approaches have enabled characterizations of the community composition of numerous gut microbial communities, which in turn has enhanced interest in their diversity and functional relationships in different groups of vertebrates. Although fishes represent the greatest taxonomic and ecological diversity of vertebrates, our understanding of their gut microbiota and its functional significance has lagged well behind that of terrestrial vertebrates. In order to highlight emerging issues, we provide an overview of research on fish gut microbiotas and the biology of their hosts. We conclude that microbial community composition must be viewed within an informed context of host ecology and physiology, and that this is of particular importance with respect to research planning and sampling design.
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Affiliation(s)
- Kendall D Clements
- School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand
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47
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Sanders JG, Powell S, Kronauer DJC, Vasconcelos HL, Frederickson ME, Pierce NE. Stability and phylogenetic correlation in gut microbiota: lessons from ants and apes. Mol Ecol 2014; 23:1268-1283. [PMID: 24304129 DOI: 10.1111/mec.12611] [Citation(s) in RCA: 184] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 11/22/2013] [Accepted: 11/27/2013] [Indexed: 01/02/2023]
Abstract
Correlation between gut microbiota and host phylogeny could reflect codiversification over shared evolutionary history or a selective environment that is more similar in related hosts. These alternatives imply substantial differences in the relationship between host and symbiont, but can they be distinguished based on patterns in the community data themselves? We explored patterns of phylogenetic correlation in the distribution of gut bacteria among species of turtle ants (genus Cephalotes), which host a dense gut microbial community. We used 16S rRNA pyrosequencing from 25 Cephalotes species to show that their gut community is remarkably stable, from the colony to the genus level. Despite this overall similarity, the existing differences among species' microbiota significantly correlated with host phylogeny. We introduced a novel analytical technique to test whether these phylogenetic correlations are derived from recent bacterial evolution, as would be expected in the case of codiversification, or from broader shifts more likely to reflect environmental filters imposed by factors such as diet or habitat. We also tested this technique on a published data set of ape microbiota, confirming earlier results while revealing previously undescribed patterns of phylogenetic correlation. Our results indicated a high degree of partner fidelity in the Cephalotes microbiota, suggesting that vertical transmission of the entire community could play an important role in the evolution and maintenance of the association. As additional comparative microbiota data become available, the techniques presented here can be used to explore trends in the evolution of host-associated microbial communities.
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Affiliation(s)
- Jon G Sanders
- Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA, 02138, USA
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48
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Fiorelli LE, Ezcurra MD, Hechenleitner EM, Argañaraz E, Taborda JR, Trotteyn MJ, von Baczko MB, Desojo JB. The oldest known communal latrines provide evidence of gregarism in Triassic megaherbivores. Sci Rep 2013; 3:3348. [PMID: 24287957 DOI: 10.1038/srep03348] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 10/29/2013] [Indexed: 11/09/2022] Open
Abstract
Defecation in communal latrines is a common behaviour of extant mammals widely distributed among megaherbivores. This behaviour has key social functions with important biological and ecological implications. Herbivore communal latrines are only documented among mammals and their fossil record is exceptionally restricted to the late Cenozoic. Here we report the discovery of several massive coprolite associations in the Middle-Late Triassic of the Chañares Formation, Argentina, which represent fossil communal latrines based on a high areal density, small areal extension and taphonomic attributes. Several lines of evidence (size, morphology, abundance and coprofabrics) and their association with kannemeyeriiform dicynodonts indicate that these large synapsids produced the communal latrines and had a gregarious behaviour comparable to that of extant megaherbivores. This is the first evidence of megaherbivore communal latrines in non-mammal vertebrates, indicating that this mammal-type behaviour was present in distant relatives of mammals, and predates its previous oldest record by 220 Mya.
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Reisz RR. “Pelycosaur”-Grade Synapsids: Introduction. In: Kammerer CF, Angielczyk KD, Fröbisch J, editors. Early Evolutionary History of the Synapsida. Dordrecht: Springer Netherlands; 2014. pp. 3-5. [DOI: 10.1007/978-94-007-6841-3_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Abstract
BACKGROUND Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. METHODOLOGY/PRINCIPAL FINDINGS We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days). Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. CONCLUSIONS/SIGNIFICANCE Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size), and derived titanosaurs and diplodocoids independently evolved the highest known tooth replacement rates among archosaurs.
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Affiliation(s)
- Michael D D'Emic
- Anatomical Sciences Department, Stony Brook University, Health Sciences Center, School of Medicine, Stony Brook, New York, USA.
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