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Poropat SF, Frauenfelder TG, Mannion PD, Rigby SL, Pentland AH, Sloan T, Elliott DA. Sauropod dinosaur teeth from the lower Upper Cretaceous Winton Formation of Queensland, Australia and the global record of early titanosauriforms. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220381. [PMID: 35845848 PMCID: PMC9277269 DOI: 10.1098/rsos.220381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
The Upper Cretaceous Winton Formation of Queensland, Australia, has produced several partial sauropod skeletons, but cranial remains-including teeth-remain rare. Herein, we present the first description of sauropod teeth from this formation, based on specimens from three separate sites. An isolated tooth and a dentary fragment from the Diamantinasaurus matildae type locality are considered to be referable to that titanosaurian taxon. A single tooth from the D. matildae referred specimen site is similarly regarded as being part of that individual. Seventeen teeth from a new site that are morphologically uniform, and similar to the teeth from the two Diamantinasaurus sites, are assigned to Diamantinasauria. All sauropod teeth recovered from the Winton Formation to date are compressed-cone-chisel-shaped, have low slenderness index values (2.00-2.88), are lingually curved at their apices, mesiodistally convex on their lingual surfaces, and lack prominent carinae and denticles. They are markedly different from the chisel-like teeth of derived titanosaurs, more closely resembling the teeth of early branching members of the titanosauriform radiation. This provides further support for a 'basal' titanosaurian position for Diamantinasauria. Scanning electron microscope microwear analysis of the wear facets of several teeth reveals more scratches than pits, implying that diamantinasaurians were mid-height (1-10 m) feeders. With a view to assessing the spatio-temporal distribution of sauropod tooth morphotypes before and after deposition of the Winton Formation, we provide a comprehensive continent-by-continent review of the early titanosauriform global record (Early to early Late Cretaceous). This indicates that throughout the Early-early Late Cretaceous, sauropod faunas transitioned from being quite diverse at higher phylogenetic levels and encompassing a range of tooth morphologies at the start of the Berriasian, to faunas comprising solely titanosaurs with limited dental variability by the end-Turonian. Furthermore, this review highlights the different ways in which this transition unfolded on each continent, including the earliest records of titanosaurs with narrow-crowned teeth on each continent.
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Affiliation(s)
- Stephen F. Poropat
- Australian Age of Dinosaurs Natural History Museum, The Jump-Up, Winton, Queensland 4735, Australia
- School of Science, Computing and Engineering Technologies, Swinburne University of Technology, John Street, Hawthorn, Victoria 3122, Australia
| | - Timothy G. Frauenfelder
- School of Environmental and Rural Science, University of New England, Armidale, New South Wales 2351, Australia
| | - Philip D. Mannion
- Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK
| | - Samantha L. Rigby
- Australian Age of Dinosaurs Natural History Museum, The Jump-Up, Winton, Queensland 4735, Australia
- School of Science, Computing and Engineering Technologies, Swinburne University of Technology, John Street, Hawthorn, Victoria 3122, Australia
| | - Adele H. Pentland
- Australian Age of Dinosaurs Natural History Museum, The Jump-Up, Winton, Queensland 4735, Australia
- School of Science, Computing and Engineering Technologies, Swinburne University of Technology, John Street, Hawthorn, Victoria 3122, Australia
| | - Trish Sloan
- Australian Age of Dinosaurs Natural History Museum, The Jump-Up, Winton, Queensland 4735, Australia
| | - David A. Elliott
- Australian Age of Dinosaurs Natural History Museum, The Jump-Up, Winton, Queensland 4735, Australia
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Fiorelli LE, Martinelli AG, da Silva JI, Hechenleitner EM, Soares MVT, Silva Junior JCG, da Silva JC, Borges ÉMR, Ribeiro LCB, Marconato A, Basilici G, da Silva Marinho T. First titanosaur dinosaur nesting site from the Late Cretaceous of Brazil. Sci Rep 2022; 12:5091. [PMID: 35332244 PMCID: PMC8948192 DOI: 10.1038/s41598-022-09125-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 03/17/2022] [Indexed: 11/25/2022] Open
Abstract
Titanosaurs were successful herbivorous dinosaurs widely distributed in all continents during the Cretaceous, with the major diversity in South America. The success of titanosaurs was probably due to several physiological and ecological factors, in addition to a series of morphological traits they achieved during their evolutionary history. However, the generalist nesting behaviour using different palaeoenvironments and strategies was key to accomplish that success. Titanosaur nesting sites have been found extensively around the world, with notable records in Spain, France, Romania, India, and, especially, Argentina. Here, we describe the first titanosaur nesting site from the Late Cretaceous of Brazil that represents the most boreal nesting site for South America. Several egg-clutches, partially preserved, isolated eggs and many eggshell fragments were discovered in an Inceptisol palaeosol profile of the mining Lafarge Quarry, at the Ponte Alta District (Uberaba Municipality, Minas Gerais State), corresponding to the Serra da Galga Formation (Bauru Group, Bauru Basin). Although classical mechanical preparation and CT scans have not revealed embryonic remains in ovo, the eggs and eggshell features match those eggs containing titanosaurian embryos found worldwide. The morphology of the egg-clutches and observations of the sedimentary characteristics bolster the hypothesis that these sauropods were burrow-nester dinosaurs, as was already suggested for the group based on other nesting sites. The egg-clutches distributed in two levels along the Lafarge outcrops, together with the geopalaeontological data collected, provide clear evidence for the first colonial nesting and breeding area of titanosaur dinosaurs in Brazil.
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Affiliation(s)
- Lucas E Fiorelli
- Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR-CONICET-Provincia de La Rioja-UNLaR-SEGEMAR-UNCa), Entre Ríos y Mendoza S/N, CP 5301, Anillaco, La Rioja, Argentina.
| | - Agustín G Martinelli
- Sección Paleontología de Vertebrados, Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"-CONICET, Av. Ángel Gallardo 470, C1405DJR, Buenos Aires, Argentina. .,Centro de Pesquisas Paleontológicas L. I. Price, Complexo Cultural e Científico Peirópolis, Pró-Reitoria de Extensão Universitária, Universidade Federal do Triângulo Mineiro, Rua Estanislau Collenghi 194, Uberaba, Minas Gerais, 38039-755, Brazil.
| | - João Ismael da Silva
- Centro de Pesquisas Paleontológicas L. I. Price, Complexo Cultural e Científico Peirópolis, Pró-Reitoria de Extensão Universitária, Universidade Federal do Triângulo Mineiro, Rua Estanislau Collenghi 194, Uberaba, Minas Gerais, 38039-755, Brazil.,Fundação Cultural de Uberaba, Prefeitura Municipal de Uberaba, Praça Rui Barbosa 356, Uberaba, Minas Gerais, 38010-250, Brazil
| | - E Martín Hechenleitner
- Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR-CONICET-Provincia de La Rioja-UNLaR-SEGEMAR-UNCa), Entre Ríos y Mendoza S/N, CP 5301, Anillaco, La Rioja, Argentina.,Instituto de Biología de la Conservación y Paleobiología (IBICOPA), DACEFYN-CENIIT-UNLaR, Av. Luis M. de La Fuente S/N, CP 5300, Anillaco, La Rioja, Argentina
| | - Marcus Vinícius Theodoro Soares
- Department of Geology and Natural Resources, Institute of Geosciences, State University of Campinas, Rua Carlos Gomes 250, Campinas, São Paulo, 13083-870, Brazil
| | - Julian C G Silva Junior
- Centro de Pesquisas Paleontológicas L. I. Price, Complexo Cultural e Científico Peirópolis, Pró-Reitoria de Extensão Universitária, Universidade Federal do Triângulo Mineiro, Rua Estanislau Collenghi 194, Uberaba, Minas Gerais, 38039-755, Brazil.,Laboratório de Paleontologia de Ribeirão Preto, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo, 14040-901, Brazil
| | - José Carlos da Silva
- Faculdades Associadas de Uberaba (FAZU), Fundação Educacional para o Desenvolvimento das Ciências Agrárias (FUNDAGRI), Associação Brasileira dos Criadores de Zebu (ABCZ), Av. do Tutuna, 720, Tutunas, Uberaba, Minas Gerais, 38061-500, Brazil
| | - Élbia Messias Roteli Borges
- Escola Estadual Presidente João Pinheiro, Rua Menelick de Carvalho 383, Boa Vista, Uberaba, Minas Gerais, 38017-070, Brazil
| | - Luiz Carlos Borges Ribeiro
- Centro de Pesquisas Paleontológicas L. I. Price, Complexo Cultural e Científico Peirópolis, Pró-Reitoria de Extensão Universitária, Universidade Federal do Triângulo Mineiro, Rua Estanislau Collenghi 194, Uberaba, Minas Gerais, 38039-755, Brazil.,Faculdades Associadas de Uberaba (FAZU), Fundação Educacional para o Desenvolvimento das Ciências Agrárias (FUNDAGRI), Associação Brasileira dos Criadores de Zebu (ABCZ), Av. do Tutuna, 720, Tutunas, Uberaba, Minas Gerais, 38061-500, Brazil
| | - André Marconato
- Departamento de Geologia Sedimentar e Ambiental, Instituto de Geociências, Universidade de São Paulo, Rua Do Lago, 562, Cidade Universitária, São Paulo, 05580-080, Brazil
| | - Giorgio Basilici
- Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR-CONICET-Provincia de La Rioja-UNLaR-SEGEMAR-UNCa), Entre Ríos y Mendoza S/N, CP 5301, Anillaco, La Rioja, Argentina.,Department of Geology and Natural Resources, Institute of Geosciences, State University of Campinas, Rua Carlos Gomes 250, Campinas, São Paulo, 13083-870, Brazil
| | - Thiago da Silva Marinho
- Centro de Pesquisas Paleontológicas L. I. Price, Complexo Cultural e Científico Peirópolis, Pró-Reitoria de Extensão Universitária, Universidade Federal do Triângulo Mineiro, Rua Estanislau Collenghi 194, Uberaba, Minas Gerais, 38039-755, Brazil.,Instituto de Ciências Exatas, Naturais e Educação (ICENE), Universidade Federal do Triângulo Mineiro (UFTM), Av. Randolfo Borges Jr. 1400, Univerdecidade, Uberaba, Minas Gerais, 38064-200, Brazil
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Chiarenza AA, Mannion PD, Farnsworth A, Carrano MT, Varela S. Climatic constraints on the biogeographic history of Mesozoic dinosaurs. Curr Biol 2021; 32:570-585.e3. [PMID: 34921764 DOI: 10.1016/j.cub.2021.11.061] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/15/2021] [Accepted: 11/24/2021] [Indexed: 12/13/2022]
Abstract
Dinosaurs dominated Mesozoic terrestrial ecosystems globally. However, whereas a pole-to-pole geographic distribution characterized ornithischians and theropods, sauropods were restricted to lower latitudes. Here, we evaluate the role of climate in shaping these biogeographic patterns through the Jurassic-Cretaceous (201-66 mya), combining dinosaur fossil occurrences, past climate data from Earth System models, and habitat suitability modeling. Results show that, uniquely among dinosaurs, sauropods occupied climatic niches characterized by high temperatures and strongly bounded by minimum cold temperatures. This constrained the distribution and dispersal pathways of sauropods to tropical areas, excluding them from latitudinal extremes, especially in the Northern Hemisphere. The greater availability of suitable habitat in the southern continents, particularly in the Late Cretaceous, might be key to explaining the high diversity of sauropods there, relative to northern landmasses. Given that ornithischians and theropods show a flattened or bimodal latitudinal biodiversity gradient, with peaks at higher latitudes, the closer correspondence of sauropods to a subtropical concentration could hint at fundamental thermophysiological differences to the other two clades.
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Affiliation(s)
- Alfio Alessandro Chiarenza
- Grupo de Ecología Animal, Centro de Investigacion Mariña, Universidade de Vigo, Campus Lagoas-Marcosende, Vigo 36310, Spain; Department of Earth Science and Engineering, Imperial College London, Prince Consort Road, London SW7 2BP, UK; Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK.
| | - Philip D Mannion
- Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK.
| | - Alex Farnsworth
- School of Geographical Sciences, University of Bristol, University Road, Bristol BS8 1RL, UK; State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Matthew T Carrano
- Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, P.O. Box 37012, MRC 121, Washington, DC 20013-7012, USA.
| | - Sara Varela
- Grupo de Ecología Animal, Centro de Investigacion Mariña, Universidade de Vigo, Campus Lagoas-Marcosende, Vigo 36310, Spain
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Maidment SCR, Strachan SJ, Ouarhache D, Scheyer TM, Brown EE, Fernandez V, Johanson Z, Raven TJ, Barrett PM. Bizarre dermal armour suggests the first African ankylosaur. Nat Ecol Evol 2021; 5:1576-1581. [PMID: 34556830 DOI: 10.1038/s41559-021-01553-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 08/09/2021] [Indexed: 11/09/2022]
Abstract
Ankylosauria is a diverse clade of armoured dinosaurs whose members were important constituents of many Cretaceous faunas. Phylogenetic analyses imply that the clade diverged from its sister taxon, Stegosauria, during the late Early Jurassic, but the fossil records of both clades are sparse until the Late Jurassic (~150 million years ago). Moreover, Ankylosauria is almost entirely restricted to former Laurasian continents, with only a single valid Gondwanan taxon. Spicomellus afer gen. et sp. nov. appears to represent the earliest-known ankylosaur and the first to be named from Africa, from the Middle Jurassic (Bathonian-Callovian) of Morocco, filling an important gap in dinosaur evolution. The specimen consists of a rib with spiked dermal armour fused to its dorsal surface, an unprecedented morphology among extinct and extant vertebrates. The specimen reveals an unrealized morphological diversity of armoured dinosaurs during their early evolution, and implies the presence of an important but undiscovered Gondwanan fossil record.
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Affiliation(s)
- Susannah C R Maidment
- Department of Earth Sciences, Natural History Museum, London, UK. .,School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK.
| | - Sarah J Strachan
- Department of Earth Sciences, University College London, London, UK
| | - Driss Ouarhache
- GERA Laboratory, Faculty of Sciences Dhar El Mahraz, SMBA University, Fez, Morocco
| | - Torsten M Scheyer
- Palaeontological Institute and Museum, University of Zurich, Zurich, Switzerland
| | - Emily E Brown
- Department of Earth Sciences, Natural History Museum, London, UK.,School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK
| | | | - Zerina Johanson
- Department of Earth Sciences, Natural History Museum, London, UK
| | - Thomas J Raven
- Department of Earth Sciences, Natural History Museum, London, UK.,School of Environment and Technology, University of Brighton, Brighton, UK
| | - Paul M Barrett
- Department of Earth Sciences, Natural History Museum, London, UK.,Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
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Doran Brownstein C. Dinosaurs from the Santonian-Campanian Atlantic coastline substantiate phylogenetic signatures of vicariance in Cretaceous North America. ROYAL SOCIETY OPEN SCIENCE 2021; 8:210127. [PMID: 34457333 PMCID: PMC8385347 DOI: 10.1098/rsos.210127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 08/02/2021] [Indexed: 06/13/2023]
Abstract
During the Cretaceous, diversifications and turnovers affected terrestrial vertebrates experiencing the effects of global geographical change. However, the poor fossil record from the early Late Cretaceous has concealed how dinosaurs and other terrestrial vertebrates responded to these events. I describe two dinosaurs from the Santonian to Early Campanian of the obscure North American paleolandmass Appalachia. A revised look at a large, potentially novel theropod shows that it likely belongs to a new clade of tyrannosauroids solely from Appalachia. Another partial skeleton belongs to an early member of the Hadrosauridae, a highly successful clade of herbivorous dinosaurs. This skeleton is associated with the first small juvenile dinosaur specimens from the Atlantic Coastal Plain. The tyrannosauroid and hadrosaurid substantiate one of the only Late Santonian dinosaur faunas and help pinpoint the timing of important anatomical innovations in two widespread dinosaur lineages. The phylogenetic positions of the tyrannosauroid and hadrosaurid show Santonian Appalachian dinosaur faunas are comparable to coeval Eurasian ones, and the presence of clades formed only by Appalachian dinosaur taxa establishes a degree of endemism in Appalachian dinosaur assemblages attributable to episodes of vicariance.
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Affiliation(s)
- Chase Doran Brownstein
- Stamford Museum and Nature Center, Stamford, CT, USA
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
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Poropat SF, Kundrát M, Mannion PD, Upchurch P, Tischler TR, Elliott DA. Second specimen of the Late Cretaceous Australian sauropod dinosaur Diamantinasaurus matildae provides new anatomical information on the skull and neck of early titanosaurs. Zool J Linn Soc 2021. [DOI: 10.1093/zoolinnean/zlaa173] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
The titanosaurian sauropod dinosaur Diamantinasaurus matildae is represented by two individuals from the Cenomanian–lower Turonian ‘upper’ Winton Formation of central Queensland, north-eastern Australia. The type specimen has been described in detail, whereas the referred specimen, which includes several elements not present in the type series (partial skull, atlas, axis and postaxial cervical vertebrae), has only been described briefly. Herein, we provide a comprehensive description of this referred specimen, including a thorough assessment of the external and internal anatomy of the braincase, and identify several new autapomorphies of D. matildae. Via an expanded data matrix consisting of 125 taxa scored for 552 characters, we recover a close, well-supported relationship between Diamantinasaurus and its contemporary, Savannasaurus elliottorum. Unlike previous iterations of this data matrix, under a parsimony framework we consistently recover Diamantinasaurus and Savannasaurus as early-diverging members of Titanosauria using both equal weighting and extended implied weighting, with the overall topology largely consistent between analyses. We erect a new clade, named Diamantinasauria herein, that also includes the contemporaneous Sarmientosaurus musacchioi from southern Argentina, which shares several cranial features with the referred Diamantinasaurus specimen. Thus, Diamantinasauria is represented in the mid-Cretaceous of both South America and Australia, supporting the hypothesis that some titanosaurians, in addition to megaraptoran theropods and possibly some ornithopods, were able to disperse between these two continents via Antarctica. Conversely, there is no evidence for rebbachisaurids in Australia, which might indicate that they were unable to expand into high latitudes before their extinction in the Cenomanian–Turonian. Likewise, there is no evidence for titanosaurs with procoelous caudal vertebrae in the mid-Cretaceous Australian record, despite scarce but compelling evidence for their presence in both Antarctica and New Zealand during the Campanian–Maastrichtian. These later titanosaurs presumably dispersed into these landmasses from South America before the Campanian (~85 Mya), when seafloor spreading between Zealandia and Australia commenced. Although Australian mid-Cretaceous dinosaur faunas appear to be cosmopolitan at higher taxonomic levels, closer affinities with South America at finer scales are becoming better supported for sauropods, theropods and ornithopods.
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Affiliation(s)
- Stephen F Poropat
- Faculty of Science, Engineering and Technology, Swinburne University of Technology, John Street, Hawthorn, VIC, Australia
- Australian Age of Dinosaurs Museum of Natural History, The Jump-Up, Winton, QLD, Australia
| | - Martin Kundrát
- Center for Interdisciplinary Biosciences, Technology and Innovation Park, University of Pavol Jozef Šafárik, Košice, Slovakia
| | - Philip D Mannion
- Department of Earth Sciences, University College London, Gower Street, London, UK
| | - Paul Upchurch
- Department of Earth Sciences, University College London, Gower Street, London, UK
| | - Travis R Tischler
- Australian Age of Dinosaurs Museum of Natural History, The Jump-Up, Winton, QLD, Australia
| | - David A Elliott
- Australian Age of Dinosaurs Museum of Natural History, The Jump-Up, Winton, QLD, Australia
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Hechenleitner EM, Leuzinger L, Martinelli AG, Rocher S, Fiorelli LE, Taborda JRA, Salgado L. Two Late Cretaceous sauropods reveal titanosaurian dispersal across South America. Commun Biol 2020; 3:622. [PMID: 33110212 PMCID: PMC7591563 DOI: 10.1038/s42003-020-01338-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 09/29/2020] [Indexed: 11/09/2022] Open
Abstract
South American titanosaurians have been central to the study of the evolution of Cretaceous sauropod dinosaurs. Despite their remarkable diversity, the fragmentary condition of several taxa and the scarcity of records outside Patagonia and southwestern Brazil have hindered the study of continental-scale paleobiogeographic relationships. We describe two new Late Cretaceous titanosaurians from Quebrada de Santo Domingo (La Rioja, Argentina), which help to fill a gap between these main areas of the continent. Our phylogenetic analysis recovers both new species, and several Brazilian taxa, within Rinconsauria. The data suggest that, towards the end of the Cretaceous, this clade spread throughout southern South America. At the same locality, we discovered numerous accumulations of titanosaurian eggs, likely related to the new taxa. With eggs distributed in three levels along three kilometres, the new site is one of the largest ever found and provides further evidence of nesting site philopatry among Titanosauria.
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Affiliation(s)
- E Martín Hechenleitner
- Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR), Provincia de La Rioja, UNLaR, SEGEMAR, UNCa, CONICET, Entre Ríos y Mendoza s/n (5301), Anillaco, La Rioja, Argentina. .,Instituto de Biología de la Conservación y Paleobiología (IBICOPA), DACEFyN-UNLaR, 5300, La Rioja, Argentina.
| | - Léa Leuzinger
- Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR), Provincia de La Rioja, UNLaR, SEGEMAR, UNCa, CONICET, Entre Ríos y Mendoza s/n (5301), Anillaco, La Rioja, Argentina.,Laboratorio de Paleontología de Vertebrados, Departamento de Ciencias Geológicas, Facultad de Ciencias Exactas y Naturales, Pabellón II, Universidad de Buenos Aires, Intendente Güiraldes 2160, Ciudad Universitaria (C1428EGA), Buenos Aires, Argentina
| | - Agustín G Martinelli
- CONICET-Sección Paleontología de Vertebrados, Museo Argentino de Ciencias Naturales "Bernardino Rivadavia", Av. Ángel Gallardo 470, C1405 DJR, Buenos Aires, Argentina
| | - Sebastián Rocher
- Instituto de Geología y Recursos Naturales, Centro de Investigación e Innovación Tecnológica, Universidad Nacional de La Rioja (INGeReN-CENIIT-UNLaR), Av. Gob. Vernet y Apóstol Felipe, 5300, La Rioja, Argentina
| | - Lucas E Fiorelli
- Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR), Provincia de La Rioja, UNLaR, SEGEMAR, UNCa, CONICET, Entre Ríos y Mendoza s/n (5301), Anillaco, La Rioja, Argentina
| | - Jeremías R A Taborda
- Centro de Investigaciones en Ciencias de la Tierra (CICTERRA), Universidad Nacional de Córdoba, CONICET, FCEFyN, Vélez Sarsfield 1611, Ciudad Universitaria, X5016GCA, Córdoba, Argentina
| | - Leonardo Salgado
- Instituto de Investigación en Paleobiología y Geología, Universidad Nacional de Río Negro-CONICET, Av. Presidente Julio A. Roca 1242, 8332, General Roca, Río Negro, Argentina
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Kubo T. Biogeographical Network Analysis of Cretaceous Terrestrial Tetrapods: A Phylogeny-Based Approach. Syst Biol 2020; 68:1034-1051. [PMID: 31135923 DOI: 10.1093/sysbio/syz024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 03/13/2019] [Accepted: 04/09/2019] [Indexed: 11/13/2022] Open
Abstract
Network methods are widely used to represent and analyze biogeography. It is difficult, however, to convert occurrence data of fossil vertebrates to a biogeographical network, as most species were known from a single locality. A new method for creating a biogeographical network that can incorporate phylogenetic information is proposed in this study, which increases the number of edges in the network of fossil vertebrates and enables the application of various network methods. Using ancestral state reconstruction via maximum parsimony, the method first estimates the biogeographical regions of all internal nodes of a given phylogeny using biogeographical information on the terminal taxa. Then, each internal node in the phylogenetic tree is converted to an edge in the biogeographical network that connects the region(s), if unambiguously estimated, of its two descendants. The new method was applied to phylogenetic trees generated by a birth-death model. Under all conditions tested, an average of $CDATA[$CDATA[$>$$70% of the internal nodes in phylogenetic trees were converted into edges. Three network indices-link density, average link weight, and endemism index (EI)-were evaluated for their usefulness in comparing different biogeographical networks. The EI reflects the rate of dispersal; the other indices reflect nonbiogeographical parameters, the number of taxa and regions, which highlights the importance of evaluating network indices before applying them to biogeographical studies. Multiple Cretaceous biogeographical networks were constructed from the phylogenies of five tetrapod taxa: terrestrial crocodyliforms, terrestrial turtles, nonavian dinosaurs, avians, and pterosaurs. The networks of avians and pterosaurs showed similar topologies and a strong correlation, and unexpectedly high endemism indices. These similarities were probably a result of shared taphonomic biases (i.e., the Lagerstätten effect) for volant taxa with fragile skeletons. The crocodyliform network was partitioned into the Gondwanan and Laurasian continents. The dinosaur network was partitioned into three groups of continents: 1) North America, Asia, and Australia; 2) Europe and Africa; and 3) India, Madagascar, and South America. When Early and Late Cretaceous dinosaurs were analyzed separately, the dinosaur networks were divided into 1) North America, Asia, and Australia; and 2) Europe, Africa, India, and South America for the Early Cretaceous and 1) North America, Asia, and Europe; and 2) India, Madagascar, and South America for the Late Cretaceous. This partitioning of dinosaur and crocodyliform networks corroborates the results of previous biogeographical studies and indicates that the method introduced here can retrieve biogeographical signals from a source phylogeny when sufficient data are available for most targeted biogeographical regions.
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Affiliation(s)
- Tai Kubo
- The University Museum, The University of Tokyo, 7-3-1 Hongo, Bunkyou-ku, Tokyo 113-0033, Japan
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10
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Button DJ, Zanno LE. Repeated Evolution of Divergent Modes of Herbivory in Non-avian Dinosaurs. Curr Biol 2020; 30:158-168.e4. [DOI: 10.1016/j.cub.2019.10.050] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 09/08/2019] [Accepted: 10/25/2019] [Indexed: 01/13/2023]
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11
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Han F, Xu X, Sullivan C, Huang L, Guo Y, Wu R. New titanosauriform (Dinosauria: Sauropoda) specimens from the Upper Cretaceous Daijiaping Formation of southern China. PeerJ 2019; 7:e8237. [PMID: 31875155 PMCID: PMC6927344 DOI: 10.7717/peerj.8237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 11/19/2019] [Indexed: 11/20/2022] Open
Abstract
Titanosauriform sauropod dinosaurs were once considered rare in the Upper Cretaceous of Asia, but a number of titanosauriforms from this stratigraphic interval have been discovered in China in recent years. In fact, all adequately known Cretaceous Asian sauropods are titanosauriforms, but only a few have been well studied, lending significance to any new anatomical information that can be extracted from Asia’s Cretaceous sauropod record. Here we give a detailed description of some titanosauriform bones recovered recently from the Upper Cretaceous Daijiaping Formation of Tianyuan County, Zhuzhou City, Hunan Province, southern China. The occurrence of this material in Hunan increases the known geographic range of titanosauriforms in eastern Asia. Although all of the specimens discussed in this paper can be assigned to Titanosauriformes at least tentatively, some bones display a limited number of features that are more typical of basal sauropods and/or derived diplodocoids, suggesting complex patterns of character evolution within Neosauropoda.
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Affiliation(s)
- Fenglu Han
- School of Earth Sciences, China University of Geosciences (Wuhan), Wuhan, China
| | - Xing Xu
- Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China.,CAS Center for Excellence in Life and Paleoenvironment, Beijing, China
| | - Corwin Sullivan
- Department of Biological Sciences, University of Alberta, Edmonton, Canada.,Philip J. Currie Dinosaur Museum, Wembley, Canada
| | - Leqing Huang
- Hunan Institute of Geological Survey, Changsha, China
| | - Yu Guo
- The Geological Museum of China, Beijing, China
| | - Rui Wu
- School of Earth Sciences, China University of Geosciences (Wuhan), Wuhan, China
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12
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Mannion PD, Upchurch P, Jin X, Zheng W. New information on the Cretaceous sauropod dinosaurs of Zhejiang Province, China: impact on Laurasian titanosauriform phylogeny and biogeography. ROYAL SOCIETY OPEN SCIENCE 2019; 6:191057. [PMID: 31598266 PMCID: PMC6731702 DOI: 10.1098/rsos.191057] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 08/01/2019] [Indexed: 05/11/2023]
Abstract
Titanosaurs were a globally distributed clade of Cretaceous sauropods. Historically regarded as a primarily Gondwanan radiation, there is a growing number of Eurasian taxa, with several putative titanosaurs contemporaneous with, or even pre-dating, the oldest known Southern Hemisphere remains. The early Late Cretaceous Jinhua Formation, in Zhejiang Province, China, has yielded two putative titanosaurs, Jiangshanosaurus lixianensis and Dongyangosaurus sinensis. Here, we provide a detailed re-description and diagnosis of Jiangshanosaurus, as well as new anatomical information on Dongyangosaurus. Previously, a 'derived' titanosaurian placement for Jiangshanosaurus was primarily based on the presence of procoelous anterior caudal centra. We show that this taxon had amphicoelous anterior-middle caudal centra. Its only titanosaurian synapomorphy is that the dorsal margins of the scapula and coracoid are approximately level with one another. Dongyangosaurus can clearly be differentiated from Jiangshanosaurus, and displays features that indicate a closer relationship to the titanosaur radiation. Revised scores for both taxa are incorporated into an expanded phylogenetic data matrix, comprising 124 taxa scored for 548 characters. Under equal weights parsimony, Jiangshanosaurus is recovered as a member of the non-titanosaurian East Asian somphospondylan clade Euhelopodidae, and Dongyangosaurus lies just outside of Titanosauria. However, when extended implied weighting is applied, both taxa are placed within Titanosauria. Most other 'middle' Cretaceous East Asian sauropods are probably non-titanosaurian somphospondylans, but at least Xianshanosaurus appears to belong to the titanosaur radiation. Our analyses also recover the Early Cretaceous European sauropod Normanniasaurus genceyi as a 'derived' titanosaur, clustering with Gondwanan taxa. These results provide further support for a widespread diversification of titanosaurs by at least the Early Cretaceous.
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Affiliation(s)
- Philip D. Mannion
- Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK
| | - Paul Upchurch
- Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK
| | - Xingsheng Jin
- Zhejiang Museum of Natural History, Hangzhou, Zhejiang 310014, People's Republic of China
- State Key Laboratory of Palaeobiology and Stratigraphy (Nanjing Institute of Geology and Palaeontology, CAS), Nanjing, Jiangsu 210008, People's Republic of China
| | - Wenjie Zheng
- Zhejiang Museum of Natural History, Hangzhou, Zhejiang 310014, People's Republic of China
- State Key Laboratory of Palaeobiology and Stratigraphy (Nanjing Institute of Geology and Palaeontology, CAS), Nanjing, Jiangsu 210008, People's Republic of China
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13
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Riga BJG, Lamanna MC, Otero A, David LDO, Kellner AWA, Ibiricu LM. An overview of the appendicular skeletal anatomy of South American titanosaurian sauropods, with definition of a newly recognized clade. AN ACAD BRAS CIENC 2019; 91:e20180374. [PMID: 31340217 DOI: 10.1590/0001-3765201920180374] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 01/28/2019] [Indexed: 11/22/2022] Open
Abstract
In the last two decades, the number of phylogenetically informative anatomical characters recognized in the appendicular skeleton of titanosaurian sauropod dinosaurs has increased dramatically with the discovery of new and comparatively complete specimens. Here we provide an overview of the appendicular skeletal morphology of South American titanosaurs and discuss its significance for phylogenetic reconstruction. The appendicular skeletal diversity of South American titanosaurs is substantially greater than was initially appreciated. Moreover, some regions of the appendicular skeleton, such as the pes, exhibit remarkable variability in form. Multiple synapomorphies of Titanosauria and the less inclusive clades Lithostrotia and Saltasauridae consist of characters of the girdles and limbs. Although the phylogenetic definitions of titanosaurian clades such as Saltasaurinae and Lognkosauria are stable, the taxonomic content of these clades has varied in recent analyses depending on the phylogenetic topology recovered. Within Titanosauria, the results of four recent, largely independent analyses support the existence of a derived titanosaurian lineage distinct from the 'Saltasaurinae line,' which is herein termed Colossosauria. At present, this clade is mainly comprised by taxa within Lognkosauria and Rinconsauria, and is useful in discussions of titanosaurian lower-level relationships.
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Affiliation(s)
- Bernardo J González Riga
- CONICET/Laboratorio y Museo de Dinosaurios, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Padre Contreras 1300, Parque Gral. San Martin, Mendoza Capital 5500, Mendoza, Argentina
| | - Matthew C Lamanna
- Section of Vertebrate Paleontology, Carnegie Museum of Natural History, 4400 Forbes Avenue, Pittsburgh, Pennsylvania 15213, U.S.A
| | - Alejandro Otero
- CONICET, División Paleontología de Vertebrados, Museo de La Plata, Paseo del Bosque, s/n, La Plata, B1900FWA, Argentina
| | - Leonardo D Ortiz David
- CONICET/Laboratorio y Museo de Dinosaurios, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Padre Contreras 1300, Parque Gral. San Martin, Mendoza Capital 5500, Mendoza, Argentina
| | - Alexander W A Kellner
- Laboratório de Systemática e Tafonomia de Vertebrados Fósseis, Departamento de Geologia e Paleontologia, Museu Nacional, Universidade Federal do Rio de Janeiro, Quinta da Boa Vista, São Cristóvão, 20940-040 Rio de Janeiro, RJ, Brazil
| | - Lucio M Ibiricu
- Instituto Patagónico de Geología y Paleontología (IPGP-CONICET), Boulevard Almirante Brown, 2915, Puerto Madryn, 9120, Chubut, Argentina
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14
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Klopfstein S, Spasojevic T. Illustrating phylogenetic placement of fossils using RoguePlots: An example from ichneumonid parasitoid wasps (Hymenoptera, Ichneumonidae) and an extensive morphological matrix. PLoS One 2019; 14:e0212942. [PMID: 30939174 PMCID: PMC6445432 DOI: 10.1371/journal.pone.0212942] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 02/12/2019] [Indexed: 11/19/2022] Open
Abstract
The fossil record constitutes the primary source of information about the evolutionary history of extant and extinct groups, and many analyses of macroevolution rely on fossils that are accurately placed within phylogenies. To avoid misinterpretation of the fossil record, especially by non-palaeontologists, the proper assessment and communication of uncertainty in fossil placement is crucial. We here use Bayesian morphological phylogenetics to evaluate the classifications of fossil parasitoid wasps (Hymenoptera, Ichneumonidae) and introduce 'RoguePlots' to illustrate placement uncertainty on the phylogeny of extant taxa. Based on an extensive, newly constructed morphological matrix of 222 characters in 24 fossil and 103 extant taxa, we test three different aspects of models of morphological evolution. We find that a model that includes ordered characters, among-character rate variation, and a state-space restricted to observed states achieves the highest marginal likelihoods. The individual RoguePlots reveal large differences in confidence in the placement of the different fossils and allow some refinements to their classification: Polyhelictes bipolarus and Ichninsum appendicrassum are moved from an uncertain subfamily placement to Pimplinae, Plectiscidea lanhami is transferred to Allomacrus in Cylloceriinae (Allomacrus lanhami, comb. nov.), Lithotorus cressoni is moved from Diplazontinae to Orthocentrinae, and we note uncertainty in the generic placements of Rhyssella? vera and Xanthopimpla? messelensis. We discuss potential artefacts that might result in biased posterior probabilities in Bayesian morphological phylogenetic analyses, pertaining to character and taxon sampling, fossilization biases, and model misspecification. Finally, we suggest future directions both in ichneumonid palaeontology and in the way RoguePlots can improve both assessment and representation of placement uncertainty, both in fossils and other rogue taxa.
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Affiliation(s)
- Seraina Klopfstein
- Naturhistorisches Museum Basel, Biowissenschaften, Basel, Switzerland
- University of Bern, Institute of Ecology and Evolution, Bern, Switzerland
- Naturhistorisches Museum Bern, Department of Invertebrates, Bern, Switzerland
| | - Tamara Spasojevic
- University of Bern, Institute of Ecology and Evolution, Bern, Switzerland
- Naturhistorisches Museum Bern, Department of Invertebrates, Bern, Switzerland
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15
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Gorscak E, O’Connor PM. A new African Titanosaurian Sauropod Dinosaur from the middle Cretaceous Galula Formation (Mtuka Member), Rukwa Rift Basin, Southwestern Tanzania. PLoS One 2019; 14:e0211412. [PMID: 30759122 PMCID: PMC6374010 DOI: 10.1371/journal.pone.0211412] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 01/14/2019] [Indexed: 11/18/2022] Open
Abstract
The African terrestrial fossil record has been limited in its contribution to our understanding of both regional and global Cretaceous paleobiogeography, an interval of significant geologic and macroevolutionary change. A common component in Cretaceous African faunas, titanosaurian sauropods diversified into one of the most specious groups of dinosaurs worldwide. Here we describe the new titanosaurian Mnyamawamtuka moyowamkia gen. et sp. nov. from the Mtuka Member of the Galula Formation in southwest Tanzania. The new specimen preserves teeth, elements from all regions of the postcranial axial skeleton, parts of both appendicular girdles, and portions of both limbs including a complete metatarsus. Unique traits of M. moyowamkia include the lack of an interpostzygapophyseal lamina in posterior dorsal vertebrae, pronounced posterolateral expansion of middle caudal centra, and an unusually small sternal plate. Phylogenetic analyses consistently place M. moyowamkia as either a close relative to lithostrotian titanosaurians (e.g., parsimony, uncalibrated Bayesian analyses) or as a lithostrotian and sister taxon to Malawisaurus dixeyi from the nearby Aptian? Dinosaur Beds of Malawi (e.g., tip-dating Bayesian analyses). M. moyowamkia shares a few features with M. dixeyi, including semi-spatulate teeth and a median lamina between the neural canal and interpostzygapophyseal lamina in anterior dorsal vertebrae. Both comparative morphology and phylogenetic analyses support Mnyamawamtuka as a distinct and distant relative to Rukwatitan bisepultus and Shingopana songwensis from the younger Namba Member of the Galula Formation with these results largely congruent with newly constrained ages for the Mtuka Member (Aptian–Cenomanian) and Namba Member (Campanian). Coupled with recent discoveries from the Dahkla Oasis, Egypt (e.g., Mansourasaurus shahinae) and other parts of continental Afro-Arabia, the Tanzania titanosaurians refine perspectives on the development of African terrestrial faunas throughout the Cretaceous—a critical step in understanding non-marine paleobiogeographic patterns of Africa that have remained elusive until the past few years.
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Affiliation(s)
- Eric Gorscak
- Department of Anatomy, Midwestern University, Downers Grove, Illinois, United States of America
- Integrative Research Center, Field Museum of Natural History, Chicago, Illinois, United States of America
- Department of Biological Sciences, Ohio University, Athens, Ohio, United States of America
- Department of Biomedical Sciences, Ohio University Heritage College of Osteopathic Medicine, Athens, Ohio, United States of America
- Ohio Center for Ecology and Evolutionary Studies, Ohio University, Athens, Ohio, United States of America
- * E-mail:
| | - Patrick M. O’Connor
- Department of Biomedical Sciences, Ohio University Heritage College of Osteopathic Medicine, Athens, Ohio, United States of America
- Ohio Center for Ecology and Evolutionary Studies, Ohio University, Athens, Ohio, United States of America
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16
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Mannion PD, Upchurch P, Schwarz D, Wings O. Taxonomic affinities of the putative titanosaurs from the Late Jurassic Tendaguru Formation of Tanzania: phylogenetic and biogeographic implications for eusauropod dinosaur evolution. Zool J Linn Soc 2019. [DOI: 10.1093/zoolinnean/zly068] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Philip D Mannion
- Department of Earth Science and Engineering, Imperial College London, London, UK
| | - Paul Upchurch
- Department of Earth Sciences, University College London, London, UK
| | | | - Oliver Wings
- Niedersächsisches Landesmuseum Hannover, Hannover, Germany
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17
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Wright AM. Editor's note on 'Putting fossils in trees' special issue. Biol Lett 2018; 13:rsbl.2017.0103. [PMID: 28330978 DOI: 10.1098/rsbl.2017.0103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 03/02/2017] [Indexed: 11/12/2022] Open
Affiliation(s)
- April M Wright
- Ecology, Evolution and Organismal Biology, Iowa State University, Ames, IA 50010, USA .,The Field Museum, Chicago, IL 60605, USA
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18
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Sallam HM, Gorscak E, O'Connor PM, El-Dawoudi IA, El-Sayed S, Saber S, Kora MA, Sertich JJW, Seiffert ER, Lamanna MC. New Egyptian sauropod reveals Late Cretaceous dinosaur dispersal between Europe and Africa. Nat Ecol Evol 2018; 2:445-451. [PMID: 29379183 DOI: 10.1038/s41559-017-0455-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 12/15/2017] [Indexed: 11/09/2022]
Abstract
Prominent hypotheses advanced over the past two decades have sought to characterize the Late Cretaceous continental vertebrate palaeobiogeography of Gondwanan landmasses, but have proved difficult to test because terrestrial vertebrates from the final ~30 million years of the Mesozoic are extremely rare and fragmentary on continental Africa (including the then-conjoined Arabian Peninsula but excluding the island of Madagascar). Here we describe a new titanosaurian sauropod dinosaur, Mansourasaurus shahinae gen. et sp. nov., from the Upper Cretaceous (Campanian) Quseir Formation of the Dakhla Oasis of the Egyptian Western Desert. Represented by an associated partial skeleton that includes cranial elements, Mansourasaurus is the most completely preserved land-living vertebrate from the post-Cenomanian Cretaceous (~94-66 million years ago) of the African continent. Phylogenetic analyses demonstrate that Mansourasaurus is nested within a clade of penecontemporaneous titanosaurians from southern Europe and eastern Asia, thereby providing the first unambiguous evidence for a post-Cenomanian Cretaceous continental vertebrate clade that inhabited both Africa and Europe. The close relationship of Mansourasaurus to coeval Eurasian titanosaurians indicates that terrestrial vertebrate dispersal occurred between Eurasia and northern Africa after the tectonic separation of the latter from South America ~100 million years ago. These findings counter hypotheses that dinosaur faunas of the African mainland were completely isolated during the post-Cenomanian Cretaceous.
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Affiliation(s)
- Hesham M Sallam
- Mansoura University Vertebrate Paleontology Center, Department of Geology, Faculty of Science, Mansoura University, Mansoura, Egypt.
| | - Eric Gorscak
- Department of Biological Sciences, Ohio University, Athens, OH, USA.,Ohio Center for Ecology and Evolutionary Studies, Ohio University, Athens, OH, USA.,Integrative Research Center, The Field Museum of Natural History, Chicago, IL, USA
| | - Patrick M O'Connor
- Ohio Center for Ecology and Evolutionary Studies, Ohio University, Athens, OH, USA.,Department of Biomedical Sciences, Ohio University Heritage College of Osteopathic Medicine, Athens, OH, USA
| | - Iman A El-Dawoudi
- Mansoura University Vertebrate Paleontology Center, Department of Geology, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Sanaa El-Sayed
- Mansoura University Vertebrate Paleontology Center, Department of Geology, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Sara Saber
- Mansoura University Vertebrate Paleontology Center, Department of Geology, Faculty of Science, Mansoura University, Mansoura, Egypt.,Department of Geology, Faculty of Science, Assiut University, Assiut, Egypt
| | - Mahmoud A Kora
- Mansoura University Vertebrate Paleontology Center, Department of Geology, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Joseph J W Sertich
- Department of Earth Sciences, Denver Museum of Nature and Science, Denver, CO, USA
| | - Erik R Seiffert
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Matthew C Lamanna
- Section of Vertebrate Paleontology, Carnegie Museum of Natural History, Pittsburgh, PA, USA
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19
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Gonzàlez Riga BJ, Mannion PD, Poropat SF, Ortiz David LD, Coria JP. Osteology of the Late Cretaceous Argentinean sauropod dinosaur Mendozasaurus neguyelap: implications for basal titanosaur relationships. Zool J Linn Soc 2018. [DOI: 10.1093/zoolinnean/zlx103] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Bernardo J Gonzàlez Riga
- Laboratorio y Museo de Dinosaurios, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mendoza, Argentina
| | - Philip D Mannion
- Department of Earth Science and Engineering, Imperial College London, London, UK
| | - Stephen F Poropat
- Department of Chemistry and Biotechnology, Swinburne University of Technology, John St, Hawthorn, Australia
- Australian Age of Dinosaurs Museum of Natural History, The Jump-Up, Winton, Queensland, Australia
| | - Leonardo D Ortiz David
- Laboratorio y Museo de Dinosaurios, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mendoza, Argentina
| | - Juan Pedro Coria
- Laboratorio y Museo de Dinosaurios, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
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20
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Altimiras J, Lindgren I, Giraldo-Deck LM, Matthei A, Garitano-Zavala Á. Aerobic performance in tinamous is limited by their small heart. A novel hypothesis in the evolution of avian flight. Sci Rep 2017; 7:15964. [PMID: 29162941 PMCID: PMC5698454 DOI: 10.1038/s41598-017-16297-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 11/09/2017] [Indexed: 12/13/2022] Open
Abstract
Some biomechanical studies from fossil specimens suggest that sustained flapping flight of birds could have appeared in their Mesozoic ancestors. We challenge this idea because a suitable musculoskeletal anatomy is not the only requirement for sustained flapping flight. We propose the “heart to fly” hypothesis that states that sustained flapping flight in modern birds required an enlargement of the heart for the aerobic performance of the flight muscles and test it experimentally by studying tinamous, the living birds with the smallest hearts. The small ventricular size of tinamous reduces cardiac output without limiting perfusion pressures, but when challenged to fly, the heart is unable to support aerobic metabolism (quick exhaustion, larger lactates and post-exercise oxygen consumption and compromised thermoregulation). At the same time, cardiac growth shows a crocodilian-like pattern and is correlated with differential gene expression in MAPK kinases. We integrate this physiological evidence in a new evolutionary scenario in which the ground-up, short and not sustained flapping flight displayed by tinamous represents an intermediate step in the evolution of the aerobic sustained flapping flight of modern birds.
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Affiliation(s)
- Jordi Altimiras
- AVIAN Behavioral Genomics and Physiology, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden.
| | - Isa Lindgren
- AVIAN Behavioral Genomics and Physiology, Department of Physics, Chemistry and Biology, Linköping University, Linköping, Sweden
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21
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Borths MR, Stevens NJ. The first hyaenodont from the late Oligocene Nsungwe Formation of Tanzania: Paleoecological insights into the Paleogene-Neogene carnivore transition. PLoS One 2017; 12:e0185301. [PMID: 29020030 PMCID: PMC5636082 DOI: 10.1371/journal.pone.0185301] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 09/05/2017] [Indexed: 11/25/2022] Open
Abstract
Throughout the Paleogene, most terrestrial carnivore niches in Afro-Arabia were occupied by Hyaenodonta, an extinct lineage of placental mammals. By the end of the Miocene, terrestrial carnivore niches had shifted to members of Carnivora, a clade with Eurasian origins. The transition from a hyaenodont-carnivore fauna to a carnivoran-carnivore fauna coincides with other ecological changes in Afro-Arabia as tectonic conditions in the African Rift System altered climatic conditions and facilitated faunal exchange with Eurasia. Fossil bearing deposits in the Nsungwe Formation in southwestern Tanzania are precisely dated to ~25.2 Ma (late Oligocene), preserving a late Paleogene Afro-Arabian fauna on the brink of environmental transition, including the earliest fossil evidence of the split between Old World monkeys and apes. Here we describe a new hyaenodont from the Nsungwe Formation, Pakakali rukwaensis gen. et sp. nov., a bobcat-sized taxon known from a portion of the maxilla that preserves a deciduous third premolar and alveoli of dP4 and M1. The crown of dP3 bears an elongate parastyle and metastyle and a small, blade-like metacone. Based on alveolar morphology, the two more distal teeth successively increased in size and had relatively large protocones. Using a hyaenodont character-taxon matrix that includes deciduous dental characters, Bayesian phylogenetic methods resolve Pakakali within the clade Hyainailouroidea. A Bayesian biogeographic analysis of phylogenetic results resolve the Pakakali clade as Afro-Arabian in origin, demonstrating that this small carnivorous mammal was part of an endemic Afro-Arabian lineage that persisted into the Miocene. Notably, Pakakali is in the size range of carnivoran forms that arrived and began to diversify in the region by the early Miocene. The description of Pakakali is important for exploring hyaenodont ontogeny and potential influences of Afro-Arabian tectonic events upon mammalian evolution, providing a deep time perspective on the stability of terrestrial carnivore niches through time.
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Affiliation(s)
- Matthew R. Borths
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, United States of America
- Center for Ecology and Evolutionary Studies, Ohio University, Athens, Ohio, United States of America
| | - Nancy J. Stevens
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, Ohio, United States of America
- Center for Ecology and Evolutionary Studies, Ohio University, Athens, Ohio, United States of America
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22
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Carballido JL, Pol D, Otero A, Cerda IA, Salgado L, Garrido AC, Ramezani J, Cúneo NR, Krause JM. A new giant titanosaur sheds light on body mass evolution among sauropod dinosaurs. Proc Biol Sci 2017; 284:20171219. [PMID: 28794222 PMCID: PMC5563814 DOI: 10.1098/rspb.2017.1219] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 07/06/2017] [Indexed: 11/12/2022] Open
Abstract
Titanosauria was the most diverse and successful lineage of sauropod dinosaurs. This clade had its major radiation during the middle Early Cretaceous and survived up to the end of that period. Among sauropods, this lineage has the most disparate values of body mass, including the smallest and largest sauropods known. Although recent findings have improved our knowledge on giant titanosaur anatomy, there are still many unknown aspects about their evolution, especially for the most gigantic forms and the evolution of body mass in this clade. Here we describe a new giant titanosaur, which represents the largest species described so far and one of the most complete titanosaurs. Its inclusion in an extended phylogenetic analysis and the optimization of body mass reveals the presence of an endemic clade of giant titanosaurs inhabited Patagonia between the Albian and the Santonian. This clade includes most of the giant species of titanosaurs and represents the major increase in body mass in the history of Titanosauria.
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Affiliation(s)
- José L Carballido
- CONICET, Museo Paleontológico Egidio Feruglio, Trelew U9100GYO, Argentina
| | - Diego Pol
- CONICET, Museo Paleontológico Egidio Feruglio, Trelew U9100GYO, Argentina
| | - Alejandro Otero
- CONICET, División Paleontología de Vertebrados, Museo de La Plata, La Plata B1900FWA, Argentina
| | - Ignacio A Cerda
- CONICET, Instituto de Investigación en Paleobiología y Geología, Universidad Nacional de Río Negro, General Roca 8332, Argentina
| | - Leonardo Salgado
- CONICET, Instituto de Investigación en Paleobiología y Geología, Universidad Nacional de Río Negro, General Roca 8332, Argentina
| | - Alberto C Garrido
- Museo Provincial de Ciencias Naturales 'Juan Olsacher', Zapala 8340, Argentina
- Departamento Geología y Petróleo, Facultad de Ingeniería, Universidad Nacional del Comahue, Neuquén 8400, Argentina
| | - Jahandar Ramezani
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Néstor R Cúneo
- CONICET, Museo Paleontológico Egidio Feruglio, Trelew U9100GYO, Argentina
| | - Javier M Krause
- CONICET, Museo Paleontológico Egidio Feruglio, Trelew U9100GYO, Argentina
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Torcida Fernández-Baldor F, Canudo JI, Huerta P, Moreno-Azanza M, Montero D. Europatitan eastwoodi, a new sauropod from the lower Cretaceous of Iberia in the initial radiation of somphospondylans in Laurasia. PeerJ 2017; 5:e3409. [PMID: 28674644 PMCID: PMC5490465 DOI: 10.7717/peerj.3409] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 05/12/2017] [Indexed: 11/20/2022] Open
Abstract
The sauropod of El Oterillo II is a specimen that was excavated from the Castrillo de la Reina Formation (Burgos, Spain), late Barremian–early Aptian, in the 2000s but initially remained undescribed. A tooth and elements of the axial skeleton, and the scapular and pelvic girdle, represent it. It is one of the most complete titanosauriform sauropods from the Early Cretaceous of Europe and presents an opportunity to deepen our understanding of the radiation of this clade in the Early Cretaceous and study the paleobiogeographical relationships of Iberia with Gondwana and with other parts of Laurasia. The late Barremian–early Aptian is the time interval in the Cretaceous with the greatest diversity of sauropod taxa described in Iberia: two titanosauriforms, Tastavinsaurus and Europatitan; and a rebbachisaurid, Demandasaurus. The new sauropod Europatitan eastwoodi n. gen. n. sp. presents a series of autapomorphic characters in the presacral vertebrae and scapula that distinguish it from the other sauropods of the Early Cretaceous of Iberia. Our phylogenetic study locates Europatitan as the basalmost member of the Somphospondyli, clearly differentiated from other clades such as Brachiosauridae and Titanosauria, and distantly related to the contemporaneous Tastavinsaurus. Europatitan could be a representative of a Eurogondwanan fauna like Demandasaurus, the other sauropod described from the Castrillo de la Reina Formation. The presence of a sauropod fauna with marked Gondwananan affinities in the Aptian of Iberia reinforces the idea of faunal exchanges between this continental masses during the Early Cretaceous. Further specimens and more detailed analysis are needed to elucidate if this Aptian fauna is caused by the presence of previously unnoticed Aptian land bridges, or it represents a relict fauna from an earlier dispersal event.
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Affiliation(s)
- Fidel Torcida Fernández-Baldor
- Museo de Dinosaurios, Salas de los Infantes, Burgos, Spain.,Colectivo Arqueológico-Paleontológico Salense, Salas de los Infantes, Burgos, Spain
| | - José Ignacio Canudo
- Paleontología, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain.,Grupo Aragosaurus-IUCA, Universidad de Zaragoza, Zaragoza, Spain
| | - Pedro Huerta
- Museo de Dinosaurios, Salas de los Infantes, Burgos, Spain.,Colectivo Arqueológico-Paleontológico Salense, Salas de los Infantes, Burgos, Spain.,Departamento de Geología, Escuela Politécnica Superior de Ávila, Universidad de Salamanca, Salamanca, Spain
| | - Miguel Moreno-Azanza
- GeoBioTec, Departamento de Ciências da Terra, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal.,Museu da Lourinhã, Lourinhã, Portugal
| | - Diego Montero
- Museo de Dinosaurios, Salas de los Infantes, Burgos, Spain.,Colectivo Arqueológico-Paleontológico Salense, Salas de los Infantes, Burgos, Spain
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A Sauropod Tooth from the Santonian of Hungary and the European Late Cretaceous 'Sauropod Hiatus'. Sci Rep 2017; 7:3261. [PMID: 28607394 PMCID: PMC5468229 DOI: 10.1038/s41598-017-03602-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 05/02/2017] [Indexed: 11/16/2022] Open
Abstract
The lack of sauropod body fossils from the 20 My-long mid-Cenomanian to the late Campanian interval of the Late Cretaceous in Europe is referred to as the ‘sauropod hiatus’, with only a few footprints reported from the Apulian microplate (i.e. the southern part of the European archipelago). Here we describe a single tooth from the Santonian continental beds of Iharkút, Hungary, that represents the first European body fossil evidence of a sauropod from this critical time interval. The mosaic of derived and plesiomorphic features documented by the tooth crown morphology points to a basal titanosauriform affinity suggesting the occurrence of a clade of sauropods in the Upper Cretaceous of Europe that is quite different from the previously known Campano-Maastrichtian titanosaurs. Along with the footprints coming from shallow marine sediments, this tooth further strengthens the view that the extreme rarity of sauropod remains from this period of Europe is the result of sampling bias related to the dominance of coastal over inland sediments, in the latter of which sauropod fossils usually occur. This is also in line with the hypothesis that sauropods preferred inland habitats to swampy environments.
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Borths MR, Holroyd PA, Seiffert ER. Hyainailourine and teratodontine cranial material from the late Eocene of Egypt and the application of parsimony and Bayesian methods to the phylogeny and biogeography of Hyaenodonta (Placentalia, Mammalia). PeerJ 2016; 4:e2639. [PMID: 27867761 PMCID: PMC5111901 DOI: 10.7717/peerj.2639] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Accepted: 09/30/2016] [Indexed: 11/27/2022] Open
Abstract
Hyaenodonta is a diverse, extinct group of carnivorous mammals that included weasel- to rhinoceros-sized species. The oldest-known hyaenodont fossils are from the middle Paleocene of North Africa and the antiquity of the group in Afro-Arabia led to the hypothesis that it originated there and dispersed to Asia, Europe, and North America. Here we describe two new hyaenodont species based on the oldest hyaenodont cranial specimens known from Afro-Arabia. The material was collected from the latest Eocene Locality 41 (L-41, ∼34 Ma) in the Fayum Depression, Egypt. Akhnatenavus nefertiticyon sp. nov. has specialized, hypercarnivorous molars and an elongate cranial vault. In A. nefertiticyon the tallest, piercing cusp on M1-M2 is the paracone. Brychotherium ephalmos gen. et sp. nov. has more generalized molars that retain the metacone and complex talonids. In B. ephalmos the tallest, piercing cusp on M1-M2 is the metacone. We incorporate this new material into a series of phylogenetic analyses using a character-taxon matrix that includes novel dental, cranial, and postcranial characters, and samples extensively from the global record of the group. The phylogenetic analysis includes the first application of Bayesian methods to hyaenodont relationships. B. ephalmos is consistently placed within Teratodontinae, an Afro-Arabian clade with several generalist and hypercarnivorous forms, and Akhnatenavus is consistently recovered in Hyainailourinae as part of an Afro-Arabian radiation. The phylogenetic results suggest that hypercarnivory evolved independently three times within Hyaenodonta: in Teratodontinae, in Hyainailourinae, and in Hyaenodontinae. Teratodontines are consistently placed in a close relationship with Hyainailouridae (Hyainailourinae + Apterodontinae) to the exclusion of "proviverrines," hyaenodontines, and several North American clades, and we propose that the superfamily Hyainailouroidea be used to describe this relationship. Using the topologies recovered from each phylogenetic method, we reconstructed the biogeographic history of Hyaenodonta using parsimony optimization (PO), likelihood optimization (LO), and Bayesian Binary Markov chain Monte Carlo (MCMC) to examine support for the Afro-Arabian origin of Hyaenodonta. Across all analyses, we found that Hyaenodonta most likely originated in Europe, rather than Afro-Arabia. The clade is estimated by tip-dating analysis to have undergone a rapid radiation in the Late Cretaceous and Paleocene; a radiation currently not documented by fossil evidence. During the Paleocene, lineages are reconstructed as dispersing to Asia, Afro-Arabia, and North America. The place of origin of Hyainailouroidea is likely Afro-Arabia according to the Bayesian topologies but it is ambiguous using parsimony. All topologies support the constituent clades-Hyainailourinae, Apterodontinae, and Teratodontinae-as Afro-Arabian and tip-dating estimates that each clade is established in Afro-Arabia by the middle Eocene.
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Affiliation(s)
- Matthew R Borths
- Department of Biomedical Sciences, Ohio University , Athens, Ohio , United States
| | - Patricia A Holroyd
- Museum of Paleontology, University of California, Berkeley , Berkeley, California , United States
| | - Erik R Seiffert
- Department of Cell and Neurobiology, University of Southern California , Los Angeles, California , United States
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26
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Donoghue PCJ, Yang Z. The evolution of methods for establishing evolutionary timescales. Philos Trans R Soc Lond B Biol Sci 2016; 371:20160020. [PMID: 27325838 PMCID: PMC4920342 DOI: 10.1098/rstb.2016.0020] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/15/2016] [Indexed: 11/12/2022] Open
Abstract
The fossil record is well known to be incomplete. Read literally, it provides a distorted view of the history of species divergence and extinction, because different species have different propensities to fossilize, the amount of rock fluctuates over geological timescales, as does the nature of the environments that it preserves. Even so, patterns in the fossil evidence allow us to assess the incompleteness of the fossil record. While the molecular clock can be used to extend the time estimates from fossil species to lineages not represented in the fossil record, fossils are the only source of information concerning absolute (geological) times in molecular dating analysis. We review different ways of incorporating fossil evidence in modern clock dating analyses, including node-calibrations where lineage divergence times are constrained using probability densities and tip-calibrations where fossil species at the tips of the tree are assigned dates from dated rock strata. While node-calibrations are often constructed by a crude assessment of the fossil evidence and thus involves arbitrariness, tip-calibrations may be too sensitive to the prior on divergence times or the branching process and influenced unduly affected by well-known problems of morphological character evolution, such as environmental influence on morphological phenotypes, correlation among traits, and convergent evolution in disparate species. We discuss the utility of time information from fossils in phylogeny estimation and the search for ancestors in the fossil record.This article is part of the themed issue 'Dating species divergences using rocks and clocks'.
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Affiliation(s)
- Philip C J Donoghue
- School of Earth Sciences, University of Bristol, Life Sciences Building, Tyndall Avenue, Bristol BS8 1TQ, UK
| | - Ziheng Yang
- Department of Genetics, Evolution and Environment, University College London, Gower Street, London WC1E 6BT, UK
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Lund EK, O’Connor PM, Loewen MA, Jinnah ZA. A New Centrosaurine Ceratopsid, Machairoceratops cronusi gen et sp. nov., from the Upper Sand Member of the Wahweap Formation (Middle Campanian), Southern Utah. PLoS One 2016; 11:e0154403. [PMID: 27192148 PMCID: PMC4871575 DOI: 10.1371/journal.pone.0154403] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 04/13/2016] [Indexed: 11/19/2022] Open
Abstract
The Upper Cretaceous (middle-late Campanian) Wahweap Formation of southern Utah contains the oldest diagnostic evidence of ceratopsids (to date, all centrosaurines) in North America, with a number of specimens recovered from throughout a unit that spans between 81 and 77 Ma. Only a single specimen has been formally named, Diabloceratops eatoni, from the lower middle member of the formation. Machairoceratops cronusi gen. et sp. nov., a new centrosaurine ceratopsid from the upper member of the Wahweap Formation, is here described based on cranial material representing a single individual recovered from a calcareous mudstone. The specimen consists of two curved and elongate orbital horncores, a left jugal, a nearly complete, slightly deformed braincase, the left squamosal, and a mostly complete parietal ornamented by posteriorly projected, anterodorsally curved, elongate spikes on either side of a midline embayment. The fan-shaped, stepped-squamosal is diagnostic of Centrosaurinae, however, this element differs from the rectangular squamosal in Diabloceratops. Machairoceratops also differs in the possession of two anterodorsally (rather than laterally) curved epiparietal ornamentations on either side of a midline embayment that are distinguished by a posteromedially-oriented sulcus along the entire length of the epiparietal. Additionally, the parietosquamosal frill is lacking any other epiossifications along its periphery. Machairoceratops shares a triangular (rather than round) frill and spike-like epiparietal loci (p1) ornamentation with the stratigraphically lower Diabloceratops. Both parsimony and Bayesian phylogenetic analyses place Machairoceratops as an early-branching centrosaurine. However, the parsimony-based analysis provides little resolution for the position of the new taxon, placing it in an unresolved polytomy with Diabloceratops. The resultant Bayesian topology yielded better resolution, aligning Machairoceratops as the definitive sister taxon to a clade formed by Diabloceratops and Albertaceratops. Considered together, both phylogenetic methods unequivocally place Machairoceratops as an early-branching centrosaurine, and given the biostratigraphic position of Machairoceratops, these details increase the known ceratopsid diversity from both the Wahweap Formation and the southern portion of Laramidia. Finally, the unique morphology of the parietal ornamentation highlights the evolutionary disparity of frill ornamentation near the base of Centrosaurinae.
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Affiliation(s)
- Eric K. Lund
- Department of Biomedical Sciences, Ohio University Heritage College of Osteopathic Medicine, Athens, Ohio, United States of America
- Ohio Center for Ecology and Evolutionary Studies, Ohio University, Athens, Ohio, United States of America
- * E-mail:
| | - Patrick M. O’Connor
- Department of Biomedical Sciences, Ohio University Heritage College of Osteopathic Medicine, Athens, Ohio, United States of America
- Ohio Center for Ecology and Evolutionary Studies, Ohio University, Athens, Ohio, United States of America
| | - Mark A. Loewen
- Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah, United States of America
- Natural History Museum of Utah, Salt Lake City, Utah, United States of America
| | - Zubair A. Jinnah
- School of Geosciences, University of the Witwatersrand, Johannesburg South Africa
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