DOCSLIB.ORG

UC Davis IDAV Publications

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
UC Davis IDAV Publications UC Davis IDAV Publications Title Possibilities and limitations of three dimensional retrodeformation of a trilobite and plesiosaur vertebrae Permalink https://escholarship.org/uc/item/6tt3t5q2 Authors Motani, Ryosuke Amenta, Nina Wiley, David F. Publication Date 2005 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Nortfr American Pafeontofogy Convention DalhousieUniversity, Halifax, NovaScotia CANADA June lg-25,2005 OI'N O5 AA' R5'TO.OI'N UF TAG,T TT A{,T 5 PROGRAMMEAND ABSTRACTS $' ,t" .ir"4.ir. .'r.,.kij NAPC 2OO5 PaleoBios MUSEUMOF PALEONTOLOGY UNIVERSITYOF CALIFORNIA,BERKELEY Volume25, Supplement to number2 ISSN0031-0298 June20, 2005 NAPC2005- PaoeaeunloAaslRncls 88 the question arisesas to whether or not there symmetrical pairs of landmarks to calculate the were potentially new life modes available for three-bythree symmetric matrix that represents opportunisticmicrobes. The answeris yes, and the linear strains. Assumptionswere madethat: in particularit appearsthat calcium carbonate (1) the original animal was bilaterally number exoskeletonsof bryozoans,if not other symmetricalon average;(2) a sufficient (3) invertebrates,provided substrateopportunities. of landmarks are available; and the Other invertebrateswith similar exoskeletons deformation was linear. The results exposed could serve as alternative substrates. The difficulties causedby the violation of the three advantagesare increasingsurface areas for assumptions.First, animalscan be very incrustingand providing a variety of substrates asymmetrical:it is necessaryto identiff the more abovethe sediment-waterinterface. Our symmetricalparts of the animal and limit the preliminary studies show that the bryozoan datacollection to theseareas. Second,the exoskeletonsupport a gardenofmicroflora that number of landmark pairs neededto find the includesfilaments, diatoms, coccoliths, bacilli matrix can be quite large. The theoretical and cocci morphotypes,and extensivedeposits minimum is five pairs,but many more are of biofilm. The microbesfossilize in a similar neededbecause ofthe inherentredundancy manner to those found on the surfacesof rocks amongpairs. In the caseof the trilobite, eleven there and other sediments.The fossilizedforms pairs turnedout to be insufficient. Third, much indicatethe presenceof the following ions: Ca' are too many alternativesolutions without nearly Mg, Fe,Al, with lesserlevels of K and P. differencein symmetryscores. Therefore, Microbialroles have changed, and as the Earth symmetricalreconstruction of the originalanimal evolves,opportunistic microbes will adapt. with incorrectlengthiwidth/height ratios could easily misleadresearchers. With care,however, POSSIBILITIESAND LIMITATIONS OF it was possibleto retrodeformall the specimens. THREE DIMENSIONAL The methodwill be madeavailable in a software RETRODEFORMATIONOF A TRILOBITE package,including a 3D landmarkeditor which AND PLESIOSAURVERTEBRAE canalso be usedfor morphometricstudies. OF MOTANI, Ryosuker;Amenta, Nina:: WileY, THE EARLY EVOLUTIONARY HISTORY Davids THE EUREPTILIA (AMNIOTA, REPTILIA) rUniversityof California,Davis, Geology Dept, MUELLER, Johannesr One ShieldsAvenue, Davis, California,956l6, 2Dept. rDept. USA; ComputerSciences, UC Davis, of Biology, University of Toronto at 3lnstitute Davis, Caiifornia, 95616,USA; for Mississauga,3359 Mississar.rga Rd. N., Data Analysis and Visualization,UC Davis, Mississauga,ON, L5L lC6, Canada Davis,California, 95616, USA Besidesthe Synapsidaand the Parareptilia,the Three-dimensionalfossils have often been Eureptiliaform the third major cladeof the as deformedduring preservation' Such defonnatton Amniota and includepopular animals such usually causespronounced asymmetry, which dinosaurs,birds, crocodiles,or snakes.Their could bias the outcomeof morphometricstudies. early evolutionaryhistory, however,is only It is thereforedesirable to removethe distortions poorly understood.Early eureptilescan be probably by a geologicaldeformation model' This subdividedinto the Captorhinidae,the process,called retrodeformation,has been paraphyleticProtorothyrididae, and the basal practicedtwo-dimensionally by previous diapsidclade Araeoscelidia. A problem of this workers.We exploredthe possibrlitiesof classificationis that it is mainly basedon very few expandingthe model to threedimensions. cladisticanalyses that incltrdedonly a We usedone individual of the trilobite Phacops eureptilianrepresentatives. Thus, we are only rana and I I cervicalvertebrae ofthe poorly informed aboutthe more detailed we elasmosauridplesiosaur Thalassomedon relationshipsof basaleureptiles, and do indeed haningtonifor our study. All specimens currentlynot know ifprotorothyridids are if all apparentlyhad simple distortion,i.e., closerto diapsidsthan to captorhinids,or homogeneouscompression and,/or expansion that the taxa designatedas eureptilesdo evenbelong can be modeledby a linear transformation.We to this clade.Recent research on the early the collectedcoordinate data from the laterally Eureptiliaincluded the new descriptionof .
Load more

Recommended publications
  • 622-2014Lectureweek5
    BIOLOGY 622 – FALL 2014 BASAL AMNIOTA - STRUCTURE AND PHYLOGENY WEEK – 5 EUREPTILIA – “PROTOROTHYRIDIDAE AND ARAEOSCELIDIA S. S. SUMIDA INTRODUCTION Now that we have determined the distinction of Eureptilia and Parareptilia, and used Captorhinidae as the model of the basalmost family of eureptilians, we may now address the remaining primitive members of Eureptilia. Of course Eureptilia is a huge group, including numerous extinct groups, and all sorts of extant taxa including extant diapsids – lizards and snakes, turtles (which are probably highly derived diapsids) the remaining extant archosauromorphs – the crocodilians and the birds (derived from saurischian therapod dinosaurs). The group that was “displaced” by the Captorhinidae as the most primitive of reptilians has a somewhat complicated history. Recall that Carroll (1969) designated the family Romeriidae as the group from which all other amniotes arose. The group was named for genus Romeria, originally named by Lewellyn Price with two species – Romeria texana and R. pricei (both from the Lower Permian of Texas). In the 1970s, Heaton (1979) removed Romeria from Romeriidae, suggesting they were better placed in the Captorhinidae. This left Romeriidae without its namesake, so the name reverted to Protorothyrididae. (Carroll persisted in calling this group the “Protorothyridae”.) Nonetheless, the monophyly of the Protorothyrididae was assumed. This was in part because most workers that “included” the Protorothyrididae in any phylogenetic analyses, usually did so only by using a single representative genus to represent the entire family – usually Protorthyris or Paleothyris. For example, in the illustration following, Heaton and Reisz (1986) used only Captorhinus to represent Captorhinidae, Protorothyris to represent Protorothyrididae, and Petrolacosaurus to represent basal Diapsida.
    [Show full text]
  • Amniota: Eureptilia) from the Upper Permian of Mallorca (Balearic Islands, Western Mediterranean)
    A large multiple tooth-rowed captorhinid reptile (Amniota: Eureptilia) from the Upper Permian of Mallorca (Balearic Islands, Western Mediterranean) TORSTEN LIEBRECHT,1 JOSEP FORTUNY,2 ÀNGEL GALOBART,2 JOHANNES MÜLLER,1 and P. MARTIN SANDER,3 1 Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstraße 43, 10115 Berlin, Germany, [email protected], [email protected]; 2 Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Edifici ICTA-ICP, Carrer de les Columnes s/n, Campus de la UAB, 08193 Cerdanyola del Vallès, Barcelona, Spain, [email protected], [email protected]; 3 Steinmann-Institut für Geologie, Mineralogie und Paläontologie, Rheinische Friedrich-Wilhelms-Universität Bonn, Nussallee 8, 53115 Bonn, Germany, [email protected] Supplementary data GEOLOGIC SETTING Today, the Balearic Islands (Spanish: Islas Baleares; Catalan: Illes Balears; Fig. S1) represent the geomorphologically highest, and thus emergent, parts of the north-eastern extension of the Betic Cordillera of southern Spain. This extension is also called the Balearic Promontory, which to the northwest is separated from the Iberian mainland by the Valencia Trough, an Oligocene to recent extensional structure that has a complex tectonic history closely connected to the Alpidic collisional movements that affected the western Mediterranean realm in the Late Mesozoic and Cenozoic (Roca, 1996). The northwestern part of the Island of Mallorca is occupied by the Serra de Tramuntana (Serra del Nord), a southwest-northeast trending horst-like structure that internally is built up of southeast-dipping Alpidic thrust sheets of unmetamorphosed, predominantly calcareous rocks of Jurassic age. Exposures of Permian to Middle Triassic terrestrial redbeds (so-called ‘Permo- Triassic’) are present only at the northwestern flank of the Serra de Tramuntana in the coastal area between the villages of Estellencs and Valldemosa.
    [Show full text]
  • A Reassessment of the Taxonomic Position of Mesosaurs, and a Surprising Phylogeny of Early Amniotes
    ORIGINAL RESEARCH published: 02 November 2017 doi: 10.3389/feart.2017.00088 A Reassessment of the Taxonomic Position of Mesosaurs, and a Surprising Phylogeny of Early Amniotes Michel Laurin 1* and Graciela H. Piñeiro 2 1 CR2P (UMR 7207) Centre de Recherche sur la Paléobiodiversité et les Paléoenvironnements (Centre National de la Recherche Scientifique/MNHN/UPMC, Sorbonne Universités), Paris, France, 2 Departamento de Paleontología, Facultad de Ciencias, University of the Republic, Montevideo, Uruguay We reassess the phylogenetic position of mesosaurs by using a data matrix that is updated and slightly expanded from a matrix that the first author published in 1995 with his former thesis advisor. The revised matrix, which incorporates anatomical information published in the last 20 years and observations on several mesosaur specimens (mostly from Uruguay) includes 17 terminal taxa and 129 characters (four more taxa and five more characters than the original matrix from 1995). The new matrix also differs by incorporating more ordered characters (all morphoclines were ordered). Parsimony Edited by: analyses in PAUP 4 using the branch and bound algorithm show that the new matrix Holly Woodward, Oklahoma State University, supports a position of mesosaurs at the very base of Sauropsida, as suggested by the United States first author in 1995. The exclusion of mesosaurs from a less inclusive clade of sauropsids Reviewed by: is supported by a Bremer (Decay) index of 4 and a bootstrap frequency of 66%, both of Michael S. Lee, which suggest that this result is moderately robust. The most parsimonious trees include South Australian Museum, Australia Juliana Sterli, some unexpected results, such as placing the anapsid reptile Paleothyris near the base of Consejo Nacional de Investigaciones diapsids, and all of parareptiles as the sister-group of younginiforms (the most crownward Científicas y Técnicas (CONICET), Argentina diapsids included in the analyses).
    [Show full text]
  • Now, on to Mesozoic Marine Reptiles
    Now, on to Mesozoic Marine Reptiles NOT DINOSAURS! • They are reptiles, but some have adopted different skull fenestration • “Euryapsid” and “Anapsid” conditions are likely modified Diapsids • First reptiles returned to the sea in the Permian (Mesosaurus) How they are related: Sauropterygia Mosasauridae Thalattosuchia Dinosauria Phytosauria Lepidosauromorpha Crurotarsi Prolacertiformes Archosauromorpha Thalattosauriformes? Ichthyosauromorpha Sauria Claudiosaurus Neodiapsida Morphology • 4 basic body plans (Baupläne): (a) Thunniform advanced ichthyosaur (b) Long neck/small head plesiosaur (elasmosaur) (c) Short neck/big head pliosaur (d) Undulatory mosasaur (and basal ichthyosaur) • + “functional group 3” after Robert L. Carroll (“swimming lizards”) Morphological Trends • Limbs become rigid, often with hyperphalangy (many phalanges) • Polydactyly in ichthyosaurs Morphological Trends • (A) Merriamia (basal ichthyosaur) manus • (B) Opthalmosaurus (Jurassic ichthyosaur) manus • (C) Elasmosaurus (Cretaceous plesiosaur) manus • (D) Nothosaur pes • (E) Mosasaur pes Morphological Trends • Thoracic stiffening a usual trend • Lateral flexion directed posteriorly, or propulsion moved paraxially Carrier’s Constraint • Because of their sprawling gait, *GASP!* reptiles cannot breathe and run at the same time Ahhh… • Same applies to marine reptiles with lateral flexion (they breathe air!) *GASP!* • Solved by moving propulsion posteriorly, stiffening thorax, or moving limbs independently of spine Triassic Seas • Pangea beginning to break up • Marine
    [Show full text]
  • Homeotic Shift at the Dawn of the Turtle Evolution Rsos.Royalsocietypublishing.Org Tomasz Szczygielski
    Downloaded from http://rsos.royalsocietypublishing.org/ on April 5, 2017 Homeotic shift at the dawn of the turtle evolution rsos.royalsocietypublishing.org Tomasz Szczygielski Institute of Paleobiology, Polish Academy of Sciences, Twarda 51/55, 00-818 Warsaw, Research Poland TS, 0000-0001-5108-8493 Cite this article: Szczygielski T. 2017 Homeotic shift at the dawn of the turtle All derived turtles are characterized by one of the strongest evolution. R. Soc. open sci. 4: 160933. reductions of the dorsal elements among Amniota, and have http://dx.doi.org/10.1098/rsos.160933 only 10 dorsal and eight cervical vertebrae. I demonstrate that the Late Triassic turtles, which represent successive stages of the shell evolution, indicate that the shift of the boundary between the cervical and dorsal sections of the Received: 21 November 2016 vertebral column occurred over the course of several million Accepted: 8 March 2017 years after the formation of complete carapace. The more generalized reptilian formula of at most seven cervicals and at least 11 dorsals is thus plesiomorphic for Testudinata. The morphological modifications associated with an anterior homeotic change of the first dorsal vertebra towards the Subject Category: last cervical vertebra in the Triassic turtles are partially Biology (whole organism) recapitulated by the reduction of the first dorsal vertebra in crown-group Testudines, and they resemble the morphologies Subject Areas: observed under laboratory conditions resulting from the palaeontology/evolution/developmental experimental changes of Hox gene expression patterns. This biology homeotic shift hypothesis is supported by the, unique to turtles, restriction of Hox-5 expression domains, somitic precursors of scapula, and brachial plexus branches to the cervical region, Keywords: by the number of the marginal scute-forming placodes, which homeosis, Carnian, Norian, Pan-Testudinata, was larger in the Triassic than in modern turtles, and by patterning, palaeontology phylogenetic analyses.
    [Show full text]
  • Eureptilia, Captorhinidae, Moradisaurinae) from the Lower Permian of North-Central Texas
    UC Berkeley PaleoBios Title A juvenile of the multiple-tooth-rowed reptile Labidosaurikos (Eureptilia, Captorhinidae, Moradisaurinae) from the Lower Permian of north-central Texas Permalink https://escholarship.org/uc/item/1zz8w026 Journal PaleoBios, 34(0) ISSN 0031-0298 Authors Jung, Jason P. Sumida, Stuart S. Publication Date 2017-07-20 DOI 10.5070/P9341035708 Peer reviewed eScholarship.org Powered by the California Digital Library University of California PaleoBios 34:1–5, July 20, 2017 PaleoBios OFFICIAL PUBLICATION OF THE UNIVERSITY OF CALIFORNIA MUSEUM OF PALEONTOLOGY Jason P. Jung and Stuart S. Sumida 2017. A juvenile of the multiple-tooth- rowed reptile Labidosaurikos (Eureptilia, Captorhinidae, Moradisaurinae) from the Lower Permian of north-central Texas. Cover photo: Views of a juvenile partial maxillary toothplate of the basal reptilian Labidosaurikos. Harvard Museum of Comparative Zoology specimen MCZ 1352, scale bar=1 cm. Citation: Jung, J.P. and S.S. Sumida 2017. A juvenile of the multiple-tooth-rowed reptile Labidosaurikos (Eureptilia, Captorhinidae, Moradisauri- nae) from the Lower Permian of north-central Texas. PaleoBios, 34. ucmp_paleobios_35708. A juvenile of the multiple-tooth-rowed reptile Labidosaurikos (Eureptilia, Captorhinidae, Moradisaurinae) from the Lower Permian of north-central Texas JASON P. JUNG* and STUART S. SUMIDA Department of Biology California State University, San Bernardino 5500 University Parkway San Bernardino, California, USA 92407 [email protected] [email protected] Harvard University Museum of Comparative Zoology (MCZ) 1352 is a partial maxillary toothplate of a basal rep- tilian from the Lower Permian of Baylor County, north-central Texas. The specimen displays the straight rows of teeth characteristic of the subfamily Moradisaurinae (family: Captorhinidae) and is nearly identical in shape to the maxilla of Labidosaurikos meachami.
    [Show full text]
  • An Early Kuehneosaurid Reptile (Reptilia: Diapsida) from the Early Trias− Sic of Poland
    AN EARLY KUEHNEOSAURID REPTILE FROM THE EARLY TRIASSIC OF POLAND SUSAN E. EVANS Evans, S.E. 2009. An early kuehneosaurid reptile (Reptilia: Diapsida) from the Early Trias− sic of Poland. Palaeontologia Polonica 65, 145–178. The Early Triassic locality of Czatkowice, Poland has yielded fish, amphibians, and a series of small reptiles including procolophonians, lepidosauromorphs and archosauromorphs. The lepidosauromorphs are amongst the smallest and rarest components of the assemblage and constitute two new taxa, one of which is described and named here. Pamelina polonica shares skull and vertebral characters with the kuehneosaurs, a group of specialised long− ribbed gliders, previously known only from the Late Triassic of Britain and North America. The relationship is confirmed by cladistic analysis. Pamelina is the earliest known kuehneo− saur and provides new information about the history of this clade. It is less derived post− cranially than any of the Late Triassic taxa, but probably had at least rudimentary gliding or parachuting abilities. Key words: Reptilia, Kuehneosauridae, Triassic, Poland, gliding, Czatkowice. Susan E. Evans [[email protected]], Department of Cell and Developmental Biology, UCL, University College London, Gower Street, London, WC1E 6BT, UK. Received 1 May 2006, accepted 15 August 2007 146 SUSAN E. EVANS INTRODUCTION The Neodiapsida of Benton (1985) encompasses a wide range of diapsid lineages, most of which can be assigned to either Archosauromorpha or Lepidosauromorpha (Gauthier et al. 1988). Archosauromorpha encompasses a large and successful crown clade (Archosauria) and a series of distinctive stem lineages (e.g., protorosaurs, tanystropheiids, Prolacerta, Rhynchosauria, Trilophosauria, Evans 1988; Gauthier et al. 1988; Müller 2002, 2004; Modesto and Sues 2004).
    [Show full text]
  • A Reevaluation of Early Amniote Phylogeny
    Zoological Journal of the Linnean Society (1995), 113: 165–223. With 9 figures A reevaluation of early amniote phylogeny MICHEL LAURIN AND ROBERT R. REISZ* Department of Zoology, Erindale Campus, University of Toronto, Mississauga, Ontario, Canada L5L 1C6 Received February 1994, accepted for publication July 1994 A new phylogenetic analysis of early amniotes based on 124 characters and 13 taxa (including three outgroups) indicates that synapsids are the sister-group of all other known amniotes. The sister-group of Synapsida is Sauropsida, including Mesosauridae and Reptilia as its two main subdivisions. Reptilia is divided into Parareptilia and Eureptilia. Parareptilia includes Testudines and its fossil relatives (Procolophonidae, Pareiasauria and Millerettidae), while Eureptilia includes Diapsida and its fossil relatives (Paleothyris and Captorhinidae). Parts of the phylogeny are robust, such as the sister-group relationship between procolophonids and testudines, and between pareiasaurs and the testudinomorphs (the clade including procolophonids and testudines). Other parts of the new tree are not so firmly established, such as the position of mesosaurs as the sister-group of reptiles. The new phylogeny indicates that three major clades of amniotes extend from the present to the Palaeozoic. These three clades are the Synapsida (including Mammalia), Parareptilia (including Testudines), and Eureptilia (including Sauria). In addition, the Procolophonidae, a group of Triassic parareptiles, are the sister-group of Testudines. ADDITIONAL KEY WORDS:—Amniota – Sauropsida – Mesosauridae – Reptilia – Parareptilia – Eureptilia – Testudines – phylogenetics – evolution – Palaeozoic. CONTENTS Introduction . 166 Methods . 169 Results . 171 Amniote taxonomy . 172 Cotylosauria Cope 1880 . 173 Diadectomorpha Watson 1917 . 173 Amniota Haeckel 1866 . 177 Synapsida Osborn 1903 . 179 Sauropsida Huxley 1864 .
    [Show full text]
  • 622-2014Lectureweek7
    BIOLOGY 622 – FALL 2014 BASAL AMNIOTA - STRUCTURE AND PHYLOGENY WEEK – 7 INTRODUCTON TO PARAREPTILIA MESOSAURIA, MILLERETTIDAE and ANKYRAMORPHA: (including) LANTHANOSUCHIDAE S. S. SUMIDA INTRODUCTION We have previously noted the distinction of Eureptilia and Parareptilia, and used Captorhinidae as the model of the basal-most family of eureptilians. The story and definition of the Parareptilia, though based on a fairly simple set of concepts, has had a rather tortured taxonomic history during its relatively short life as a taxonomic term. WHY THE TERM PARAREPTILIA? As we have said, Eureptilia is a huge group, including numerous eXtinct groups, and all sorts of eXtant taxa including eXtant diapsids – lizards and snakes, turtles (which are probably highly derived diapsids) the remaining eXtant archosauromorphs – the crocodilians and the birds (derived from saurischian therapod dinosaurs). The key here is that it includes eXtant members of Reptilia. • Essentially, within the Reptilia, the Eureptilia have included those reptilian taxa that are eXtant today. • Parareptilia has functioned to include reptilian grade amniotes, buT reptilian grade amniotes that somehow are not closely related to eXtant (living, surviving) reptiles (including birds). • This has meant that the phylogenetic position of the eXtant turtles has had a lot to do with parareptilian systematics. • In recent years the [somewhat confident] resolution of the position of turtles as highly modified diapsids has removed some of the obstacles to a clearer understanding of parareptiles. This has been further facilitated by: o A host of new, in many cases younger, workers in he field, who have somwhaT fearlessly taken on this problem. Among them Modesto, Müller, Tsuji, Cisneros joining and influencing many of the researchers that have become familiar Thus far.
    [Show full text]
  • Classification and Phylogeny of the Diapsid Reptiles
    zoological Journal Ofthe Linnean Society (1985), 84: 97-164. With 17 figures Classification and phylogeny of the diapsid reptiles MICHAEL J. BENTON Department of zoology and University Museum, Parks Road, Oxford OX1 3PW, U.El. * Received June 1983, revised and accepted for publication March 1984 Reptiles with two temporal openings in the skull are generally divided into two groups-the Lepidosauria (lizards, snakes, Sphenodon, ‘eosuchians’) and the Archosauria (crocodiles, thecodontians, dinosaurs, pterosaurs). Recent suggestions that these two are not sister-groups are shown to be unproven, whereas there is strong evidence that they form a monophyletic group, the Diapsida, on the basis of several synapomorphies of living and fossil forms. A cladistic analysis of skull and skeletal characters of all described Permo-Triassic diapsid reptiles suggests some significant rearrangements to commonly held views. The genus Petrolacosaurus is the sister-group of all later diapsids which fall into two large groups-the Archosauromorpha (Pterosauria, Rhynchosauria, Prolacertiformes, Archosauria) and the Lepidosauromorpha (Younginiformes, Sphenodontia, Squamata). The pterosaurs are not archosaurs, but they are the sister-group of all other archosauromorphs. There is no close relationship betwcen rhynchosaurs and sphenodontids, nor between Prolacerta or ‘Tanystropheus and lizards. The terms ‘Eosuchia’, ‘Rhynchocephalia’ and ‘Protorosauria’ have become too wide in application and they are not used. A cladistic classification of the Diapsida is given, as well as a phylogenetic tree which uses cladistic and stratigraphic data. KEY WORDS:-Reptilia ~ Diapsida - taxonomy ~ classification - cladistics - evolution - Permian - Triassic. CONTENTS Introduction ................... 98 Historical survey .................. 99 Monophyly of the Diapsida ............... 101 Romer (1968). ................. 102 The three-taxon statements .............. 102 Lmtrup (1977) and Gardiner (1982) ...........
    [Show full text]
  • New Information on the Early Permian Lanthanosuchoid Feeserpeton Oklahomensis Based on Computed Tomography
    New information on the early Permian lanthanosuchoid Feeserpeton oklahomensis based on computed tomography Mark J. MacDougall1, Anika Winge1, Jasper Ponstein1, Maren Jansen1,2, Robert R. Reisz3 and Jörg Fröbisch1,4 1 Museum für Naturkunde Leibniz-Institute für Evolutions- und Biodiversitätsforschung, Berlin, Germany 2 Museum für Naturkunde Magdeburg, Magdeburg, Germany 3 University of Toronto Mississauga, Mississauga, ON, Canada 4 Humboldt-Universität zu Berlin, Berlin, Germany ABSTRACT The cave deposits of the Lower Permian Richards Spur locality in Oklahoma, USA, have produced an incredible number of terrestrial tetrapod taxa, many of which are currently only known from this locality. One of the many recent taxa to be described from the locality was the small lanthanosuchoid parareptile Feeserpeton oklahomensis. Represented by a well-preserved, near complete skull, F. oklahomensis would have been a small predatory reptile, likely preying upon arthropods, and contributes to the extensive tetrapod fauna that was present at Richards Spur. New computed tomography data of the holotype and only specimen has allowed us to visualize and describe previously obscured and inaccessible anatomy of this taxon. These areas include the mandibular ramus, the palate, the sphenethmoid, the epipterygoids, and the braincase. Furthermore, this new anatomical information allowed formerly unknown character codings to be updated, thus we also performed new phylogenetic analyses that incorporated this new information. The results of these updated phylogenetic analyses are very similar to those of past studies, with F. oklahomensis being found as the sister taxon to all other lanthanosuchoids. Submitted 16 May 2019 Accepted 26 August 2019 Subjects Paleontology, Zoology Published 31 October 2019 Keywords Reptilia, Cisuralian, Parareptilia, Palaeozoic, Sauropsida Corresponding author Mark J.
    [Show full text]
  • 1 the Palatal Dentition of Tetrapods and Its Functional Significance 1 2 3
    1 The palatal dentition of tetrapods and its functional significance 2 3 Ryoko Matsumoto1 and Susan E. Evans2 4 5 1 Kanagawa Prefectural Museum Natural History, Odawara, Kanagawa, Japan. 6 2 Department of Cell and Developmental Biology, University College London (UCL), London 7 UK 8 9 Corresponding author: Ryoko Matsumoto, Kanagawa Prefectural Museum Natural History, 10 499 Iryuda, Odawara, Kanagawa, 250-0031, Japan. [email protected] 11 12 Abstract 13 The presence of a palatal dentition is generally considered to be the primitive condition in 14 amniotes, with each major lineage showing a tendency toward reduction. This study 15 highlights the variation in palatal tooth arrangements and reveals clear trends within the 16 evolutionary history of tetrapods. Major changes occurred in the transition between early 17 tetrapods and amphibians on the one hand, and stem amniotes on the other. These changes 18 reflect the function of the palatal dentition, which can play an important role in holding and, 19 manipulating food during feeding. Differences in the arrangement of palatal teeth, and in their 20 pattern of loss, likely reflect differences in feeding strategy but also changes in the 21 arrangement of cranial soft tissues, as the palatal dentition works best with a well-developed 22 mobile tongue. It is difficult to explain the loss of palatal teeth in terms of any single factor, but 23 palatal tooth patterns have the potential to provide new information on diet and feeding 24 strategy in extinct taxa. 25 26 Keywords: Palatal dentition; Function; Feeding behavior; Cranial soft anatomy; Tetrapoda; 27 Amniota; Evolution. 28 29 30 1 31 Introduction 32 Any consideration of feeding in vertebrates will include detailed discussion of the marginal 33 dentition.
    [Show full text]