DOCSLIB.ORG

Terrestrial-Style Feeding in a Very Early Aquatic Tetrapod Is Supported by Evidence from Experimental Analysis of Suture Morphology

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Terrestrial-Style Feeding in a Very Early Aquatic Tetrapod Is Supported by Evidence from Experimental Analysis of Suture Morphology Terrestrial-style feeding in a very early aquatic tetrapod is supported by evidence from experimental analysis of suture morphology Molly J. Markey*† and Charles R. Marshall*‡ *Department of Earth and Planetary Sciences and ‡Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, 26 Oxford Street, Cambridge, MA 02138 Communicated by Andrew H. Knoll, Harvard University, Cambridge, MA, March 6, 2007 (received for review September 25, 2006) There is no consensus on when in the fish-tetrapod transition stega, captured prey using suction or biting (15). Specifically, the suction feeding, the primary method of prey capture in the aquatic fishes Eusthenopteron, Panderichthys, and Tiktaalik, and the early realm, evolved into the direct biting on prey typical of terrestrial tetrapod Ventastega, all possess large coronoid fangs, whereas animals. Here, we show that differences in the morphology of se- these teeth are absent in the more derived Acanthostega.In lected cranial sutures between species that span the fish–tetrapod addition, Eusthenopteron and Panderichthys both exhibit an transition (the Devonian osteolepiform fish Eusthenopteron, the ossified operculum, whereas the bony gill cover is lost in aquatic Devonian tetrapod Acanthostega, and the Permian terres- Tiktaalik, Ventastega, and Acanthostega. Finally, the glenoid fossa trial tetrapod Phonerpeton) can be used to infer when terrestrial of the articular faces posteriordorsally in the fish taxa discussed feeding first appeared. Our approach consists of defining a sutural here (Eusthenopteron, Panderichthys, and Tiktaalik) whereas, in morphospace, assigning functional fields to that morphospace the tetrapods Ventastega and Acanthostega, this fossa points based on our previous measurements of suture function made dorsally, indicating that the lower jaw changed the nature of its during feeding in the living fish Polypterus, inferring the functions articulation to the skull across the fish–tetrapod transition. (See of the fossil sutures based on where they fall in the morphospace, ref. 15 for a discussion of these changes in all taxa save Tiktaalik; and then using the correlation between feeding mode and the for Tiktaalik, see refs. 5 and 6.) These changes, along with the patterns of inferred suture function across the skull roof in taxa reduction of the gill chamber, are hypothesized to indicate a where feeding mode is unambiguous to infer the feeding mode reduced reliance on suction feeding in early tetrapods compared practiced by Acanthostega. Using this procedure, we find that the with osteolepiform fishes (15). suture morphologies of Acanthostega are inconsistent with the However, it is unclear how definitive the morphological hypothesis that it captured prey primarily by means of suction, changes described above are in helping us understand when in which suggests that it may have bitten directly on prey at or near the fish–tetrapod transition taxa were no longer dependent on the water’s edge. Thus, our data strongly support the hypothesis suction feeding. For example, extant fish that capture prey by that the terrestrial mode of feeding first emerged in aquatic taxa. means of suction exhibit an incredible variety of tooth arrange- ments and jaw shapes (see ref. 16). In addition, the loss of the Acanthostega ͉ fish–tetrapod transition ͉ suction feeding ͉ operculum observed in Acanthostega is reminiscent of the con- Eusthenopteron dition seen in the extant lungfish Neoceratodus (17), which nonetheless employs suction to capture prey (18). Therefore, he origin of tetrapods and their invasion of terrestrial whereas the changes noted above certainly indicate major Tenvironments are major events in vertebrate evolution. changes in the details of the feeding mechanisms between taxa Comparing early tetrapod taxa such as the Devonian tetrapods such as Eusthenopteron and Acanthostega, and may indicate a Acanthostega (1) and Ventastega (2) with the closely related reduced ability of Acanthostega to develop a pressure drop within osteolepiform fishes Eusthenopteron (3), Panderichthys (4), and the buccal cavity compared with Eusthenopteron, these morpho- Tiktaalik (5, 6) shows that the fish–tetrapod transition was logical changes do not enable us to determine how reliant defined by a suite of anatomical changes linked to changes in Acanthostega might have been on suction feeding, per se. locomotion, respiration, reproduction, the sensory apparatus, Thus, motivated by these uncertainties, we here provide an and feeding (7–9). approach for evaluating whether transitional tetrapods, specif- Feeding in water presents organisms with different challenges ically Acanthostega, captured prey primarily using suction, or by than those experienced when feeding on land because water is biting directly on prey items. This work follows the suggestion 900 times as dense, and 80 times as viscous, as air (10). Because that the shift from suction to biting prey capture should be of these differences, suction feeding, the most widespread reflected in the morphology of the cranial sutures of taxa that method of prey capture used by aquatic vertebrates, is impossible span the fish–tetrapod transition and the tetrapod invasion of in air (10), so animals that capture prey in terrestrial settings use land (13, 14, 19). In vivo different techniques, such as overtaking prey items with the jaws experiments demonstrate that cranial sutures are important indicators of skull function (20–23). However, no and biting on them (11). Therefore, we assume that fish pre- ceding the transition, such as Eusthenopteron, captured prey using suction, whereas later, fully terrestrial tetrapods captured Author contributions: M.J.M. and C.R.M. designed research; M.J.M. performed research; prey items by biting on them (see also ref. 12). Transitional forms M.J.M. analyzed data; and M.J.M. and C.R.M. wrote the paper. such as Acanthostega are thought to have captured prey in the The authors declare no conflict of interest. water (12–14), but the exact type of prey capture (i.e., suction Abbreviations: IF, interfrontal suture; IP, interparietal suture; IPP, interpostparietal suture; versus biting) used by Acanthostega and other early tetrapods is FP, frontoparietal suture; NF, nasofrontal suture; SMNH, Swedish Museum of Natural difficult to determine. History; MCZ, Harvard Museum of Comparative Zoology; CT, computed tomography. Stepwise morphological changes in the lower jaw, dentition, †To whom correspondence should be addressed. E-mail: [email protected]. degree of ossification of the operculum, and relative size of the This article contains supporting information online at www.pnas.org/cgi/content/full/ gill chamber in taxa that span the fish–tetrapod transition 0701706104/DC1. provide clues as to whether early tetrapods, including Acantho- © 2007 by The National Academy of Sciences of the USA 7134–7138 ͉ PNAS ͉ April 24, 2007 ͉ vol. 104 ͉ no. 17 www.pnas.org͞cgi͞doi͞10.1073͞pnas.0701706104 Downloaded by guest on September 29, 2021 previous studies have documented quantitative changes in su- IF tural morphology across the fish–tetrapod transition or linked specific sutural morphologies to specific feeding modes (e.g., Fr Fr suction feeding). Here, we assess where in the transition feeding changes occurred by (i) quantifying the three-dimensional mor- phology of selected sutures in taxa that span the fish–tetrapod Fr transition and the tetrapod invasion of land; (ii) inferring the IP function of these sutures using correlations between suture morphology and deformation during feeding in the extant fish Pa Pa Polypterus (23); and (iii) associating specific fossil suture mor- Pa phologies with aquatic (suction) feeding or terrestrial feeding (biting on prey). IP Here, the fish–tetrapod transition is represented by the os- teolepiform fish Eusthenopteron (3) and the Devonian tetrapod Acanthostega, the best-known early tetrapod (14). Although Pa Pa Panderichthys and Elpistostege are more closely related to tetra- Eusthenopteron pods than Eusthenopteron is (8), we did not have access to any panderichthyid specimens so those taxa were not included. We Fig. 1. Cross-sections through the IF and IP sutures of the osteolepiform fish Phonerpeton Eusthenopteron and their approximate positions through the skull roof (see selected the Permian terrestrial tetrapod (Dissoro- Introduction for discussion of the terminology used for these bones). The phoidea) (24) to represent the invasion of terrestrial environ- cross-section drawings are modified after the original drawings in the litera- ments by tetrapods because of its terrestrial lifestyle (24), the fact ture (29). The color of the sutural label indicates the location of the slice that its small skull size falls within the range exhibited by through the skull. The dorsal reconstruction is modified from the literature Eusthenopteron and Acanthostega (24), and the excellent three- (30) and was largely based on SMNH P222, the specimen used to generate the dimensional preservation exhibited by several specimens in the grinding series and cross-sectional drawings. [Scale bars: 1 mm (sutures) and 1 Museum of Comparative Zoology, Harvard University. cm (skull).] Fr, frontal; Pa, parietal. In this study, we are not concerned with the exact homologies between the skull roof bones of these taxa. Instead, we wish to compare bones that are similar in size, proportion (compared metrics used to quantify suture morphology in Eusthenopteron, with the rest of the skull),
Load more

Recommended publications
  • Early Tetrapod Relationships Revisited
    Biol. Rev. (2003), 78, pp. 251–345. f Cambridge Philosophical Society 251 DOI: 10.1017/S1464793102006103 Printed in the United Kingdom Early tetrapod relationships revisited MARCELLO RUTA1*, MICHAEL I. COATES1 and DONALD L. J. QUICKE2 1 The Department of Organismal Biology and Anatomy, The University of Chicago, 1027 East 57th Street, Chicago, IL 60637-1508, USA ([email protected]; [email protected]) 2 Department of Biology, Imperial College at Silwood Park, Ascot, Berkshire SL57PY, UK and Department of Entomology, The Natural History Museum, Cromwell Road, London SW75BD, UK ([email protected]) (Received 29 November 2001; revised 28 August 2002; accepted 2 September 2002) ABSTRACT In an attempt to investigate differences between the most widely discussed hypotheses of early tetrapod relation- ships, we assembled a new data matrix including 90 taxa coded for 319 cranial and postcranial characters. We have incorporated, where possible, original observations of numerous taxa spread throughout the major tetrapod clades. A stem-based (total-group) definition of Tetrapoda is preferred over apomorphy- and node-based (crown-group) definitions. This definition is operational, since it is based on a formal character analysis. A PAUP* search using a recently implemented version of the parsimony ratchet method yields 64 shortest trees. Differ- ences between these trees concern: (1) the internal relationships of aı¨stopods, the three selected species of which form a trichotomy; (2) the internal relationships of embolomeres, with Archeria
    [Show full text]
  • I Ecomorphological Change in Lobe-Finned Fishes (Sarcopterygii
    Ecomorphological change in lobe-finned fishes (Sarcopterygii): disparity and rates by Bryan H. Juarez A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science (Ecology and Evolutionary Biology) in the University of Michigan 2015 Master’s Thesis Committee: Assistant Professor Lauren C. Sallan, University of Pennsylvania, Co-Chair Assistant Professor Daniel L. Rabosky, Co-Chair Associate Research Scientist Miriam L. Zelditch i © Bryan H. Juarez 2015 ii ACKNOWLEDGEMENTS I would like to thank the Rabosky Lab, David W. Bapst, Graeme T. Lloyd and Zerina Johanson for helpful discussions on methodology, Lauren C. Sallan, Miriam L. Zelditch and Daniel L. Rabosky for their dedicated guidance on this study and the London Natural History Museum for courteously providing me with access to specimens. iii TABLE OF CONTENTS ACKNOWLEDGEMENTS ii LIST OF FIGURES iv LIST OF APPENDICES v ABSTRACT vi SECTION I. Introduction 1 II. Methods 4 III. Results 9 IV. Discussion 16 V. Conclusion 20 VI. Future Directions 21 APPENDICES 23 REFERENCES 62 iv LIST OF TABLES AND FIGURES TABLE/FIGURE II. Cranial PC-reduced data 6 II. Post-cranial PC-reduced data 6 III. PC1 and PC2 Cranial and Post-cranial Morphospaces 11-12 III. Cranial Disparity Through Time 13 III. Post-cranial Disparity Through Time 14 III. Cranial/Post-cranial Disparity Through Time 15 v LIST OF APPENDICES APPENDIX A. Aquatic and Semi-aquatic Lobe-fins 24 B. Species Used In Analysis 34 C. Cranial and Post-Cranial Landmarks 37 D. PC3 and PC4 Cranial and Post-cranial Morphospaces 38 E. PC1 PC2 Cranial Morphospaces 39 1-2.
    [Show full text]
  • Bones, Molecules, and Crown- Tetrapod Origins
    TTEC11 05/06/2003 11:47 AM Page 224 Chapter 11 Bones, molecules, and crown- tetrapod origins Marcello Ruta and Michael I. Coates ABSTRACT The timing of major events in the evolutionary history of early tetrapods is discussed in the light of a new cladistic analysis. The phylogenetic implications of this are com- pared with those of the most widely discussed, recent hypotheses of basal tetrapod interrelationships. Regardless of the sequence of cladogenetic events and positions of various Early Carboniferous taxa, these fossil-based analyses imply that the tetrapod crown-group had originated by the mid- to late Viséan. However, such estimates of the lissamphibian–amniote divergence fall short of the date implied by molecular studies. Uneven rates of molecular substitutions might be held responsible for the mismatch between molecular and morphological approaches, but the patchy quality of the fossil record also plays an important role. Morphology-based estimates of evolutionary chronology are highly sensitive to new fossil discoveries, the interpreta- tion and dating of such material, and the impact on tree topologies. Furthermore, the earliest and most primitive taxa are almost always known from very few fossil localities, with the result that these are likely to exert a disproportionate influence. Fossils and molecules should be treated as complementary approaches, rather than as conflicting and irreconcilable methods. Introduction Modern tetrapods have a long evolutionary history dating back to the Late Devonian. Their origins are rooted into a diverse, paraphyletic assemblage of lobe-finned bony fishes known as the ‘osteolepiforms’ (Cloutier and Ahlberg 1996; Janvier 1996; Ahlberg and Johanson 1998; Jeffery 2001; Johanson and Ahlberg 2001; Zhu and Schultze 2001).
    [Show full text]
  • Достающее Звено. Книга 1. Обезьяны И Все-Все-Все Серия «Primus» Серия «Достающее Звено», Книга 1
    Станислав Владимирович Дробышевский Достающее звено. Книга 1. Обезьяны и все-все-все Серия «Primus» Серия «Достающее звено», книга 1 Текст предоставлен правообладателем http://www.litres.ru/pages/biblio_book/?art=24427200 Достающее звено. Книга первая: Обезьяны и все-все-все / Станислав Дробышевский: АСТ : CORPUS; Москва; 2017 ISBN 978-5-17-099215-7 Аннотация Кто был непосредственным предком человека? Как выглядит цепь, на конце которой находится Homo sapiens, и все ли ее звенья на месте? Почему некоторые находки оказываются не тем, чем кажутся поначалу? И почему разумными стали именно гоминиды, а не другие млекопитающие? “Достающее звено” – история происхождения человека в двух книгах – подробно и увлекательно отвечает на эти и другие животрепещущие вопросы о нашем прошлом. Ведущий российский антрополог, научный редактор портала “Антропогенез.ру” и блестящий лектор Станислав Дробышевский знает об этом, вероятно, больше, чем любой другой живущий потомок палеоантропов, и как никто другой умеет заразить интересом к современной, бурно развивающейся науке, имеющей прямое отношение к каждому из нас. Первая книга посвящена тем, кто внес вклад в формирование нашего вида задолго до того, как мы встали на ноги, расправили плечи и отрастили мозг. Содержание Пролог, 8 Введение, 13 Методы познания бытия 18 Глава 1 20 Сила Духа: креационизм 22 Сила мысли: философские концепции 27 антропогенеза Сила доказательств: научные 32 концепции антропогенеза Глава 2 43 Палеоантропологические методы 43 Смежные науки 50 Глава 3 57 Особая обезьяна 67 Глава 4 67 Глава 5 77 Прямохождение 79 Рука, приспособленная к 115 использованию и изготовлению орудий Мозг 124 Тело человека от докембрия до наших 180 дней (история в четырнадцати звеньях с прологом и эпилогом) Пролог 180 Глава 6 185 Глава 7 190 Глава 8 201 Глава 9 220 Глава 10 230 Глава 11 239 Глава 12 251 Конец ознакомительного фрагмента.
    [Show full text]
  • Tetrapod Trackways from the Early Middle Devonian Period of Poland
    Vol 463 | 7 January 2010 | doi:10.1038/nature08623 ARTICLES Tetrapod trackways from the early Middle Devonian period of Poland Grzegorz Niedz´wiedzki1, Piotr Szrek2,3, Katarzyna Narkiewicz3, Marek Narkiewicz3 & Per E. Ahlberg4 The fossil record of the earliest tetrapods (vertebrates with limbs rather than paired fins) consists of body fossils and trackways. The earliest body fossils of tetrapods date to the Late Devonian period (late Frasnian stage) and are preceded by transitional elpistostegids such as Panderichthys and Tiktaalik that still have paired fins. Claims of tetrapod trackways predating these body fossils have remained controversial with regard to both age and the identity of the track makers. Here we present well-preserved and securely dated tetrapod tracks from Polish marine tidal flat sediments of early Middle Devonian (Eifelian stage) age that are approximately 18 million years older than the earliest tetrapod body fossils and 10 million years earlier than the oldest elpistostegids. They force a radical reassessment of the timing, ecology and environmental setting of the fish–tetrapod transition, as well as the completeness of the body fossil record. The last quarter-century has seen a dramatic expansion in the known Valentia Island, Ireland36, have been dated radiometrically to 385 million body fossil record of Devonian tetrapods, the earliest known limbed years ago. At the time of publication this was taken to imply an Eifelian vertebrates1–21. Equally importantly, the discovery of articulated (early Middle Devonian) age39, which clashed with the occurrence of specimens of elpistostegids, the animals that fall immediately below the Late Devonian index fossil (for Laurussia) Bothriolepis in the same them in the tetrapod stem group, has greatly enhanced our under- strata.
    [Show full text]
  • Shipman (2006)
    A reprint from American Scientist the magazine of Sigma Xi, The Scientific Research Society This reprint is provided for personal and noncommercial use. For any other use, please send a request to Permissions, American Scientist, P.O. Box 13975, Research Triangle Park, NC, 27709, U.S.A., or by electronic mail to [email protected]. ©Sigma Xi, The Scientific Research Society and other rightsholders Marginalia Missing Links and Found Links Pat Shipman hough missing links are of- sion enhanced by its four-to-nine-foot Tten talked about, it’s the found In and out of the length. Its skeleton differs markedly ones that hold a special place in my from those of crocodiles or alligators, heart. Found links are fossils that il- though, despite the overall resemblance lustrate major transitions during evo- water, transitional in body shape. Tiktaalik’s front fins hold lutionary history. More than that, such the biggest surprise. Each was a sort of creatures offer unexpected glimpses of forms from the fossil half-fin, half-leg containing the bony the never-predictable twists and turns elements found in a limb—with a func- taken by evolution. Their discovery record illuminate tional wrist, elbow and shoulder—and and surprise bring sheer fun to pale- yet retaining the bony “rays” of a fish ontology and biology. the nuts and bolts of fin. According to team member Farish I have always loved the iconic Arch- Jenkins, Jr., of Harvard University, the aeopteryx, a beautiful fossil recognized evolution front fins were sturdy enough to sup- in 1860 that unmistakably combines port the creature in very shallow water features of two major groups of ani- or on land for brief trips.
    [Show full text]
  • The Origin of Tetrapods Topic 4: the Origin of Tetrapods
    8/19/2013 Topic 4: The Origin of Tetrapods Topic 4: The Origin of Tetrapods Next two lectures will deal with: What is the geological time scale and why is it important? Origin of Tetrapods, transition from Where do herps fit in the vertebrate water to land. phylogeny? What are the evolutionary origins of Origin of Amniotes, transition to dry tetrapods? habitats. What changes were involved in the transition from water to land? The geological time scale The geological time scale Organizes the history of the earth Eon Era MYA Precambrian accounts for Cenozoic 0-65 ~88% of Earth Based on geological and biological/fossil criteria history Phanerozoic Mesozoic 65-245 We will Allows us to consider “________________” concentrate on Phanerozoic Paleozoic 245-570 Time scale over which geological and ___________________ phenomena occur st Proterozoic 570-2500 1 multicellular organisms Organized into hierarchical ________, ________, Precambrian Archaen 2500-3800 1st unicellular organisms ______________, and ______________ Age of oldest rocks Hadean 3800-4600 The Paleozoic Era The Mesozoic Era Period MYA Events Period MYA Events - Mass extinction at end of 1st _________________ Permian 245-286 Cretaceous Cretaceous 65-144 - 1st modern Squamata 1st reptiles, amphibians Carboniferous 286-320 specialize st st Devonian 360-408 1 amphibians - 1 Urodela, Anura - 1st Rynchocephalia st Jurassic 144-208 Silurian 408-438 1 jawed fishes - High reptile diversity - 1st birds 1st jawless fishes & st Ordovician 438-505 land plants -1 Angiosperms, dinosaurs, mammals 1st vertebrates Cambrian 505-570 Triassic 208-245 - 1st Testudines, ___________ 1 8/19/2013 The Cenozoic Era What are stem and crown groups? Period Epoch MYA Comments _________________ – smallest Modern humans Holocene Recent monophyletic group to contain the last common ancestor of all extant members Quanternary Evolution of humans Pleistocene 0.01-1.5 of a taxon 1st hominines Pliocene 1.5-5 _________________ – contains crown Miocene 5-24 group plus closely related extinct taxa.
    [Show full text]
  • Thermal Physiology and the Origin of Terrestriality in Vertebrates
    Blackwell Science, LtdOxford, UKZOJZoological Journal of the Linnean Society0024-4082The Lin- nean Society of London, 2005? 2005 1433 345358 Original Article ORIGIN OF TETRAPODSR. L. CARROLL ET AL. Zoological Journal of the Linnean Society, 2005, 143, 345–358. With 11 figures Thermal physiology and the origin of terrestriality in vertebrates ROBERT L. CARROLL FLS1*, JASON IRWIN2† and DAVID M. GREEN1 1Redpath Museum, McGill University, 859 Sherbrooke St. West, Montreal, Quebec, Canada, H3A 2K6 2Biology Department, Bucknell University, Lewisburg, Pennsylvania, PA 17837, USA Received January 2004; accepted for publication September 2004 The adaptive reasons for the evolutionary transition between obligatorily aquatic lobe-finned fish and facultatively terrestrial early tetrapods have long been debated. The oldest adequately known amphibians, Acanthostega and Ich- thyostega, from the final stage in the Upper Devonian (Famennian), can be clearly distinguished from the most advanced choanate sarcopterygian fish from the next older stage (Frasnian) by the presence of large pectoral and pel- vic girdles, limbs generally resembling those of later Palaeozoic land vertebrates, and the absence of bones linking the back of the skull with the shoulder girdle. Upper Devonian and most Lower Carboniferous amphibians, like their aquatic predecessors, differed significantly from modern amphibians in their much larger size, up to a metre or more in length. Animals of this size, resembling modern crocodiles and the marine iguana, could have raised their body temperatures by basking in the sun and sustained them upon re-entry into the water. It is hypothesized that the physiological advantages of thermoregulation were a major selective force that resulted in the increasing capacity for the ancestors of tetrapods to move into shallow water, and later to support their bodies against the force of gravity and increase the size and locomotor capacities of the limbs.
    [Show full text]
  • Pelvic Girdle and Fin of Tiktaalik Roseae
    Tiktaalik roseae Pelvic girdle and fin of INAUGURAL ARTICLE Neil H. Shubina,1, Edward B. Daeschlerb, and Farish A. Jenkins, Jr.c,2 aDepartment of Organismal Biology and Anatomy, The University of Chicago, Chicago, IL 60637; bAcademy of Natural Sciences of Drexel University, Philadelphia, PA 19103; and cDepartment of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138 This contribution is part of the special series of Inaugural Articles by members of the National Academy of Sciences elected in 2011. Contributed by Neil H. Shubin, December 3, 2013 (sent for review November 12, 2013) A major challenge in understanding the origin of terrestrial and tetrapods (Fig. 1). Most noticeable is that, in finned taxa, the vertebrates has been knowledge of the pelvis and hind append- entire pelvic appendage is significantly smaller than the pectoral. age of their closest fish relatives. The pelvic girdle and appendage In particular, the pelvic girdle of finned tetrapodomorphs is di- of tetrapods is dramatically larger and more robust than that of minutive relative to the pectoral: the pelvis represents a small fish and contains a number of structures that provide greater fraction of the length of the body (the maximum length of pelvis- musculoskeletal support for posture and locomotion. The discov- to-body length is 1:20 in Eusthenopteron per ref. 10). In addition, ery of pelvic material of the finned elpistostegalian, Tiktaalik there are major differences in the morphology of the pelvic gir- roseae, bridges some of these differences. Multiple isolated pelves dles of finned and limbed taxa. The girdles of Eusthenopteron and have been recovered, each of which has been prepared in three Gooloogongia have posteriorly facing acetabulae and lack sacral dimensions.
    [Show full text]
  • BOA1.2 Introduction of Amphibians.Key
    The Biology of Amphibians @ Agnes Scott College Mark Mandica Executive Director The Amphibian Foundation [email protected] 678 379 TOAD (8623) Phyllomedusidae: Agalychnis moreletii 1.2: Introduction of Amphibians Centrolenidae: Hyalinobatrachium valeroi Evolution of Amphibians † † † † Actinopterygian Coelacanth, Tetrapodomorpha †Amniota *Gerobatrachus (Ray-fin Fishes) Lungfish (stem-tetrapods) (Reptiles, Mammals)Lepospondyls † (’frogomander’) Eocaecilia GymnophionaKaraurus Caudata Triadobatrachus Anura (including Apoda Urodela Prosalirus †) Salientia Batrachia Lissamphibia *Gerobatrachus may be the sister taxon Temnospondyls † to Batrachia Tetrapods Osteichthyes Sarcopterygian (Bony Fishes) (Lobe-fin Fishes) Amphibian Reign Time Period Devonian Carboniferus Permian Triassic Jurassic Cretaceous Millions of Years Ago (420 MYA) (350 MYA) (300 MYA) (250 MYA) (200 MYA) (150-65 MYA) Present Day resembles Plate Tectonics Gondwana + Laurussia Pangea Pangea Pangea begins to break Pangea breaks present day The Biology of Amphibians amphibbio.amphibianfoundation.org Plate Tectonics Evolution of Amphibians † † † † Actinopterygian Coelacanth, Tetrapodomorpha †Amniota *Gerobatrachus (Ray-fin Fishes) Lungfish (stem-tetrapods) (Reptiles, Mammals)Lepospondyls † (’frogomander’) Eocaecilia GymnophionaKaraurus Caudata Triadobatrachus Anura (including Apoda Urodela Prosalirus †) Salientia Batrachia Lissamphibia *Gerobatrachus may be the sister taxon Temnospondyls † to Batrachia Tetrapods Osteichthyes Sarcopterygian (Bony Fishes) (Lobe-fin Fishes) Amphibian
    [Show full text]
  • Fish/Tetrapod Communities in the Upper Devonian
    Fish/tetrapod Communities Examensarbete vid Institutionen för geovetenskaper in the Upper Devonian ISSN 1650-6553 Nr 301 Maxime Delgehier Fish/tetrapod Communities Vertebrate communities including tetrapods and fishes are known from a in the Upper Devonian limited number of Late Devonian localities from several areas worldwide. These localities encompass a wide variety of environments, from true marine conditions of the near shore neritic province, to fluvial or lacustrine conditions. These localities form the foundation for a number of data matrices from which three different sets of cluster analyses were made. The first set practices a strait forward taxonomical framework using present/absent data on species and genus level to test similarity between the various localities. The second set of analyses builds on the Maxime Delgehier first one with the integration of artificial hierarchies to compensate taxonomical biases and instead infer relationship. The third also builds on the previous ones, but integrates morphological data as indicators of relationships between taxa. From this, a critical review was made for each method which comes to the conclusion that the first analysis and the first artificial level of the second analysis provide the distinctions between Frasnian and Frasnian/Famennian locality whereas the second artificial level of the second analysis and the third analysis need to be improved. Uppsala universitet, Institutionen för geovetenskaper Examensarbete D/E1/E2/E, Geologi/Hydrologi/Naturgeografi /Paleobiologi, 15/30/45
    [Show full text]
  • A New Look at the Origin of Tetrapods Per E
    Earth and Environmental Science Transactions of the Royal Society of Edinburgh, 109, 115–137, 2019 (for 2018) Early Vertebrate Evolution Follow the footprints and mind the gaps: a new look at the origin of tetrapods Per E. AHLBERG Department of Organismal Biology, Uppsala University, Norbyva¨gen 18A, 752 36 Uppsala, Sweden. Email: [email protected] ABSTRACT: The hypothesis that tetrapods evolved from elpistostegids during the Frasnian, in a predominantly aquatic context, has been challenged by the discovery of Middle Devonian tetrapod trackways predating the earliest body fossils of both elpistostegids and tetrapods. Here I present a new hypothesis based on an overview of the trace fossil and body fossil evidence. The trace fossils demonstrate that tetrapods were capable of performing subaerial lateral sequence walks before the end of the Middle Devonian. The derived morphological characters of elpistostegids and Devonian tetrapods are related to substrate locomotion, weight support and aerial vision, and thus to terres- trial competence, but the retention of lateral-line canals, gills and fin rays shows that they remained closely tied to the water. Elpistostegids and tetrapods both evolved no later than the beginning of the Middle Devonian. The earliest tetrapod records come from inland river basins, sabkha plains and ephemeral coastal lakes that preserve few, if any, body fossils; contemporary elpistostegids occur in deltas and the lower reaches of permanent rivers where body fossils are preserved. During the Frasnian, elpistostegids disappear and these riverine-deltaic environments are colonised by tetrapods. This replacement has, in the past, been misinterpreted as the origin of tetrapods. KEY WORDS: body fossils, Devonian, terrestrialisation, trackways, vertebrates.
    [Show full text]