DOCSLIB.ORG

Middle Triassic Vertebrates of India

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Middle Triassic Vertebrates of India Journal of African Earth Sciences, Vol. 29, No. 1, pp.233-241, 1999 g 1999 Elsevier Science Ltd Pergamon Pll:SO899-5382(99)00093-7 All rights reserved. Printed in Great Britain 0899.5362/99 $- see front matter Middle Triassic vertebrates of India SASWATI BANDYOPADHYAY * and DHURJATI P. SENGUPTA Geological Studies Unit, Indian Statistical Institute, 203 BT Road, Calcutta 700 035, India ABSTRACT-Until recently, the Yerrapalli Formation of the Pranhita-Godavari Valley, Deccan, India, was considered as the only Middle Triassic vertebrate-bearing horizon of. India. A new fauna1 assemblage comprising dipnoans, capitosaurids, brachyopids, trematosaurids, dicynodonts, rhynchosaurs and archosaurs has recently been recovered from the Denwa Formation of the Satpura Basin, central India. This fauna1 assemblage gives ample indications to suggest another Middle Triassic vertebrate-bearing horizon from India. The fauna1 elements of the Denwa Formation compare very well with those from the Moenkopi Formation of North America, and appear slightly older than the Yerrapalli fauna. The Bhimaram Formation, occurring immediately above the Yerrapalli and below the Carnian Maleri Formation, has also produced some capitosaurid and dicynodont fragments. An analysis of these three vertebrate-bearing horizons from India reveals that, while the Denwa and Yerrapalli Formations can be dated as Early and Middle Anisian, respectively, the Bhimaram Formation may be anywhere between Late Anisian and Ladinian. o 1999 Elsevier Science Limited. All rights reserved. RESUME-Jusqu’il y a peu, la Formation Yerrapalli de la vallee de Pranhita-Godavari (Deccan, Inde) dtait considerbe comme le seul niveau $I vertebres du Trias moyen. Une nouvelle association faunistique comprenant des dipneustes, des capitosaurides, des brachyopides, des tremato- saurides, des dicynidontes, des rhynchosaures et des archosaures a et& recemment decouverte dans la Formation de Denwa, du bassin de Saptura, en lnde centrale. Cette association faunis- tique permet de suggerer I’existence d’un nouvel horizon a vertebres du Trias moyen en Inde. Les elements faunistiques de la Formation de Denwa sont tres proches de ceux de la Formation de Moenkopi d’Amerique du Nord et apparait legerement plus vieille que la faune de Yerrapalli. La Formation de Bhimaram, qui se situe juste au-dessus de la Formation de Yerrapalli et sous la Formation de Maleri d’dge Carnien, a fournit Bgalement quelques fragments de capitosaures et de dicynodontes. Une analyse de ces trois niveaux a vertebres d’lnde revele que les Formations de Denwa et de Yerrapalli peuvent etre datees respectivement de I’Anisien inferieur et moyen, tandis que la Formation de Bhimaram se situerait entre I’Anisien superieur et le Ladinien. Q 1999 Elsevier Science Limited. All rights reserved. (Received l/7/98: revised version received 20/l O/98: accepted 16/l l/98) INTRODUCTION In India, Middle Triassic vertebrates were first immediately overlying the Yerrapalli and underlying reported by Jain et a/. (1964) from the Yerrapalli the definite Late Triassic vertebrate-bearing Maleri Formation of the Pranhita-Godavari Valley, Deccan Formation (Kutty and Sengupta, 19891, has yielded (Fig. 1 I. Anderson and Cruickshank (1978) assigned a few fragmentary vertebrate bones. Some fragmen- an Anisian age to the fauna. Apart from the Yerrapalli tary bones are also known from the Middle Triassic Formation, there were sporadic reports of fossil Denwa Formation of the Satpura Gondwana Basin vertebrate fragments of possible Middle Triassic age of central India, situated about 400 km north of the from other places in India. The Bhimaram Formation, Pranhita-Godavari Valley (Fig. 1). These reports never * Corresponding author Journal of African Earth Sciences 233 S. BANDYOPADHYA Y and D. P. SENGUPTA I I 1 780 820 86" ,yt.J IOOkm I ‘1. *i-t:> (,X.~ 24" Rewa Basr \ SatPufa Bas’n ‘:::::I;:.. .....__ .;.. : dii. ..__ CALCUTTA . yJ NAGPUR ?? Figure 1. The Gondwana basins of India. received proper attention and the Yerrapalli Formation and occasionally in the sandstone. Two new species was considered as the only definite contender for of Parotosuchus (Mukherjee and Sengupta, 19981, the Indian Middle Triassic terrestrial vertebrate- a lonchorhynchine trematosaurid (Welles, 19931, and bearing horizon. some dicynodonts (Bandyopadhyay, 1988) are known Recently, several well-preserved specimens have from the Denwa Formation. Recently, identifiable been collected from the Denwa Formation by wor- fragments of a dipnoan, Ceratodus, a brachyopid, a kers of the Indian Statistical Institute. The new fossil large- and a medium-sized dicynodont, a rhynchosaur assemblage from the Denwa has only a broad simi- and a small archosaur have been recovered from larity with that of the Yerrapalli. Some specific ele- this horizon. ments, however, suggest that a part of the Denwa Capitosaurids are the dominant temnospondyl of assemblage could be older than that of the Yerrapalli. the Denwa fauna. Hughes, in 1877, recovered a The present paper gives an account of the new fauna1 bone fragment which was described as a crocodilian elements and attempts to correlate the Denwa fauna1 scute by Lydekker (1885a). Later, this bone was assemblage with other similar faunas of the world. identified as part of a right clavicle of Mastodono- saurusindicus by Lydekker (1885b, 1890). Chatter- jee and RoyChowdhury (19741, however, doubted FAUNA FROM THE DENWA FORMATION the identification as well as the taxonomic assign- The Denwa Formation of the Satpura Basin, central ment of the specimen. They described it as a left India, conformably overlies the Pachmarhi Formation tabular and assigned it to Parotosuchus. Recently, (Table 1) of probable Permo-Triassic age. It is domin- Mukherjee and Sengupta (1998) reported two spe- ated by red mudstone which is silty in places; cies of Parotosuchus based on several well-preserved variegated coloured mudstone interbedded with cal- skull specimens. careous sandstone and palasosols are also present. The two Parotosuchus species differ from all other The vertebrate remains occur mainly in the mudstone parotosuchids by the presence of a large anterior 234 Journal of African Earth Sciences Middle Triassic vertebrates of India Table 1. The Upper Gondwana stratigraphy of the Satpura Basin (modified after Crookshank, 19361 Formations Brief Litholoav Lameta Conglomerate, limestone and mudstone ] Massive white sandstone with Jabalpur conglomerate; white and red mudstone; Ptiloph yllum flora Lower carbonaceous shale and coal lenses Cretaceous Predominant coarse conglomerate, bands of calcareous sandstone, variegated dinosaurs ? mudstone and calcareous marly lenses Unio, Ceratodus, ti capitosaurids, Predominant red mudstone, variegated brachyopid, Denwa mudstone interbedded with sandstone; trematosaurid, Middle pebbly at places; peloidal calcirudite/ dicynodonts, Triassic calcarenite rhynchosaur, archosaur White coarse-grained sandstone with Pachmarhi lenses of angular to subangular quartz temnospondyl Permo- pebbles, green shales Triassic Figure 2. Parotosuchus denwai (ISIA 54). (Al Dorsal and (~31ventral views of the skull. Scale bar= 5 cm. Journal of African Ewth Sciences S. BANDYOPADHYAYand D.P. SENGUPTA L Figure 3. Parotosuchus crookshanki IISIA 55). (A) Dorsal and (l3) ventral views of the skull. Scale bar = 5 cm. palatal vacuity, which is single and reniform but and Estes, 1969). This is the second Hadrokkosaums- longitudinally divided by a narrow and low strip of like skull found from anywhere in the world. There bone appearing inside the vacuity. One of the spe- are, however, certain important differences that cies, Parotosuchus denwai, (Fig. 2) is a large form require the Denwa brachyopid to be distinguished with a broad snout and an almost open otic notch as a separate taxon. It is also important to note that defined by posteriorly-pointed tabular horns curved the mandible and the skull of Hadrokkosaurus from at tips. The other species, Parotosuchus crookshanki the Moenkopi Formation were collected from two (Fig. 31, has a slender snout, anteromedially flattened different localities and questions have been raised tabular horns, which define a semiclosed otic notch on their being part of the same animal (Morales, (closure is more marked than that of the other spe- 19871. Jupp and Warren (19861, while working on cies), and an extremely broad body of the pterygoid temnospondyl mandibles, commented that the Ha- behind the interpterygoid vacuities. drokkosaurus mandible has many characteristics of The other temnospondyl is a brachyopid represen- an archosaur which were not apparent in any temno- ted by a well-preserved skull along with both the spondyl. It should be noted that the skull and the mandibles. The skull is typically parabolic in outline mandibles of the new brachyopid were found arti- with large anterolateral eyes, widely-spaced nares culated. Moreover, the mandible is very similar to and a deeply vaulted palate. Tabular horns and the that of Hadrokkosaurs, and the so-called archosaur otic embayment are absent. The mandible has a characters as mentioned by Jupp and Warren (1986) very long retroarticular process. Only the anterior are all present in the mandible of this new brachyopid third of the total mandible length is dentigerous. specimen. The skull roof morphology, and particularly the large A trematosaurid rostrum, represented by the tip extension of the post glenoid area of the mandible, and another fragment immediately behind that, has are comparable with
Load more

Recommended publications
  • Constraints on the Timescale of Animal Evolutionary History
    Palaeontologia Electronica palaeo-electronica.org Constraints on the timescale of animal evolutionary history Michael J. Benton, Philip C.J. Donoghue, Robert J. Asher, Matt Friedman, Thomas J. Near, and Jakob Vinther ABSTRACT Dating the tree of life is a core endeavor in evolutionary biology. Rates of evolution are fundamental to nearly every evolutionary model and process. Rates need dates. There is much debate on the most appropriate and reasonable ways in which to date the tree of life, and recent work has highlighted some confusions and complexities that can be avoided. Whether phylogenetic trees are dated after they have been estab- lished, or as part of the process of tree finding, practitioners need to know which cali- brations to use. We emphasize the importance of identifying crown (not stem) fossils, levels of confidence in their attribution to the crown, current chronostratigraphic preci- sion, the primacy of the host geological formation and asymmetric confidence intervals. Here we present calibrations for 88 key nodes across the phylogeny of animals, rang- ing from the root of Metazoa to the last common ancestor of Homo sapiens. Close attention to detail is constantly required: for example, the classic bird-mammal date (base of crown Amniota) has often been given as 310-315 Ma; the 2014 international time scale indicates a minimum age of 318 Ma. Michael J. Benton. School of Earth Sciences, University of Bristol, Bristol, BS8 1RJ, U.K. [email protected] Philip C.J. Donoghue. School of Earth Sciences, University of Bristol, Bristol, BS8 1RJ, U.K. [email protected] Robert J.
    [Show full text]
  • The Early Evolution of Rhynchosaurs Butler, Richard; Montefeltro, Felipe; Ezcurra, Martin
    University of Birmingham The early evolution of Rhynchosaurs Butler, Richard; Montefeltro, Felipe; Ezcurra, Martin DOI: 10.3389/fevo.2015.00142 License: Creative Commons: Attribution (CC BY) Document Version Publisher's PDF, also known as Version of record Citation for published version (Harvard): Butler, R, Montefeltro, F & Ezcurra, M 2016, 'The early evolution of Rhynchosaurs', Frontiers in Ecology and Evolution. https://doi.org/10.3389/fevo.2015.00142 Link to publication on Research at Birmingham portal Publisher Rights Statement: Frontiers is fully compliant with open access mandates, by publishing its articles under the Creative Commons Attribution licence (CC-BY). Funder mandates such as those by the Wellcome Trust (UK), National Institutes of Health (USA) and the Australian Research Council (Australia) are fully compatible with publishing in Frontiers. Authors retain copyright of their work and can deposit their publication in any repository. The work can be freely shared and adapted provided that appropriate credit is given and any changes specified. General rights Unless a licence is specified above, all rights (including copyright and moral rights) in this document are retained by the authors and/or the copyright holders. The express permission of the copyright holder must be obtained for any use of this material other than for purposes permitted by law. •Users may freely distribute the URL that is used to identify this publication. •Users may download and/or print one copy of the publication from the University of Birmingham research portal for the purpose of private study or non-commercial research. •User may use extracts from the document in line with the concept of ‘fair dealing’ under the Copyright, Designs and Patents Act 1988 (?) •Users may not further distribute the material nor use it for the purposes of commercial gain.
    [Show full text]
  • University of Birmingham the Earliest Bird-Line Archosaurs and The
    University of Birmingham The earliest bird-line archosaurs and the assembly of the dinosaur body plan Nesbitt, Sterling; Butler, Richard; Ezcurra, Martin; Barrett, Paul; Stocker, Michelle; Angielczyk, Kenneth; Smith, Roger; Sidor, Christian; Niedzwiedzki, Grzegorz; Sennikov, Andrey; Charig, Alan DOI: 10.1038/nature22037 License: None: All rights reserved Document Version Peer reviewed version Citation for published version (Harvard): Nesbitt, S, Butler, R, Ezcurra, M, Barrett, P, Stocker, M, Angielczyk, K, Smith, R, Sidor, C, Niedzwiedzki, G, Sennikov, A & Charig, A 2017, 'The earliest bird-line archosaurs and the assembly of the dinosaur body plan', Nature, vol. 544, no. 7651, pp. 484-487. https://doi.org/10.1038/nature22037 Link to publication on Research at Birmingham portal Publisher Rights Statement: Checked for eligibility: 03/03/2017. General rights Unless a licence is specified above, all rights (including copyright and moral rights) in this document are retained by the authors and/or the copyright holders. The express permission of the copyright holder must be obtained for any use of this material other than for purposes permitted by law. •Users may freely distribute the URL that is used to identify this publication. •Users may download and/or print one copy of the publication from the University of Birmingham research portal for the purpose of private study or non-commercial research. •User may use extracts from the document in line with the concept of ‘fair dealing’ under the Copyright, Designs and Patents Act 1988 (?) •Users may not further distribute the material nor use it for the purposes of commercial gain. Where a licence is displayed above, please note the terms and conditions of the licence govern your use of this document.
    [Show full text]
  • Gondwana Vertebrate Faunas of India: Their Diversity and Intercontinental Relationships
    438 Article 438 by Saswati Bandyopadhyay1* and Sanghamitra Ray2 Gondwana Vertebrate Faunas of India: Their Diversity and Intercontinental Relationships 1Geological Studies Unit, Indian Statistical Institute, 203 B. T. Road, Kolkata 700108, India; email: [email protected] 2Department of Geology and Geophysics, Indian Institute of Technology, Kharagpur 721302, India; email: [email protected] *Corresponding author (Received : 23/12/2018; Revised accepted : 11/09/2019) https://doi.org/10.18814/epiiugs/2020/020028 The twelve Gondwanan stratigraphic horizons of many extant lineages, producing highly diverse terrestrial vertebrates India have yielded varied vertebrate fossils. The oldest in the vacant niches created throughout the world due to the end- Permian extinction event. Diapsids diversified rapidly by the Middle fossil record is the Endothiodon-dominated multitaxic Triassic in to many communities of continental tetrapods, whereas Kundaram fauna, which correlates the Kundaram the non-mammalian synapsids became a minor components for the Formation with several other coeval Late Permian remainder of the Mesozoic Era. The Gondwana basins of peninsular horizons of South Africa, Zambia, Tanzania, India (Fig. 1A) aptly exemplify the diverse vertebrate faunas found Mozambique, Malawi, Madagascar and Brazil. The from the Late Palaeozoic and Mesozoic. During the last few decades much emphasis was given on explorations and excavations of Permian-Triassic transition in India is marked by vertebrate fossils in these basins which have yielded many new fossil distinct taxonomic shift and faunal characteristics and vertebrates, significant both in numbers and diversity of genera, and represented by small-sized holdover fauna of the providing information on their taphonomy, taxonomy, phylogeny, Early Triassic Panchet and Kamthi fauna.
    [Show full text]
  • A Taxonomic Note Concerning a Dicynodont (Synapsida: Anomodontia) from the Middle Triassic of East Africa
    Short Communication A taxonomic note concerning a dicynodont (Synapsida: Anomodontia) from the Middle Triassic of East Africa A.J. Renaut1*, R.J. Damiani1, A.M. Yates1 & P.J. Hancox2 1Bernard Price Institute for Palaeontological Research, School of Geosciences, University of the Witwatersrand, Private Bag 3, WITS, 2050 South Africa 2School of Geosciences, University of the Witwatersrand, Private Bag 3, WITS, 2050 South Africa Received 26 May 2003. Accepted 20 November 2003 The complicated histories of the Indian dicynodont Rechnisaurus and the East African dicynodont Kannemeyeria cristarhynchus has led to the incorrect use of the name ‘cristarhynchus’ for the latter taxon. This paper therefore proposes a new species name and diagnosis. Keywords: Triassic, therapsid, Kannemeyeria. INTRODUCTION previously been referred to Kannemeyeria simocephalus by Dicynodonts were a diverse clade of herbivorous, non- Keyser (1973). Keyser & Cruickshank (1979) recognized mammalian therapsids (‘mammal-like reptiles’), which that BP/1/3638 and R313 were in fact congeneric with flourished during the Permian and Triassic periods. Kannemeyeria, but a different species from Kannemeyeria Dicynodont fossils have been recorded from every simocephalus. Consequently, Keyser & Cruickshank (1979), continent and an enormous number of genera and species accepting that BP/1/3638 was conspecific with the Indian have been named, many of which are ill-diagnosed or Rechnisaurus cristarhynchus Roy-Chowdhury, argued that based on poorly preserved material (King 1988). Not Rechnisaurus was a junior synonym of Kannemeyeria. This surprisingly, the taxonomy and phylogenetic inter- recognized the new combination Kannemeyeria crista- relationships of dicynodonts remains contentious (e.g. rhynchus (Roy-Chowdhury) for the Indian and Zambian Angielczyk 2001; Hancox et al.
    [Show full text]
  • Heptasuchus Clarki, from the ?Mid-Upper Triassic, Southeastern Big Horn Mountains, Central Wyoming (USA)
    The osteology and phylogenetic position of the loricatan (Archosauria: Pseudosuchia) Heptasuchus clarki, from the ?Mid-Upper Triassic, southeastern Big Horn Mountains, Central Wyoming (USA) † Sterling J. Nesbitt1, John M. Zawiskie2,3, Robert M. Dawley4 1 Department of Geosciences, Virginia Tech, Blacksburg, VA, USA 2 Cranbrook Institute of Science, Bloomfield Hills, MI, USA 3 Department of Geology, Wayne State University, Detroit, MI, USA 4 Department of Biology, Ursinus College, Collegeville, PA, USA † Deceased author. ABSTRACT Loricatan pseudosuchians (known as “rauisuchians”) typically consist of poorly understood fragmentary remains known worldwide from the Middle Triassic to the end of the Triassic Period. Renewed interest and the discovery of more complete specimens recently revolutionized our understanding of the relationships of archosaurs, the origin of Crocodylomorpha, and the paleobiology of these animals. However, there are still few loricatans known from the Middle to early portion of the Late Triassic and the forms that occur during this time are largely known from southern Pangea or Europe. Heptasuchus clarki was the first formally recognized North American “rauisuchian” and was collected from a poorly sampled and disparately fossiliferous sequence of Triassic strata in North America. Exposed along the trend of the Casper Arch flanking the southeastern Big Horn Mountains, the type locality of Heptasuchus clarki occurs within a sequence of red beds above the Alcova Limestone and Crow Mountain formations within the Chugwater Group. The age of the type locality is poorly constrained to the Middle—early Late Triassic and is Submitted 17 June 2020 Accepted 14 September 2020 likely similar to or just older than that of the Popo Agie Formation assemblage from Published 27 October 2020 the western portion of Wyoming.
    [Show full text]
  • Sedimentology and Paleocurrent Study of the Early Triassic Rocks in the Ruhuhu Basin, SW Tanzania
    Tanzania Journal of Science 46(2): 383-396, 2020 ISSN 0856-1761, e-ISSN 2507-7961 © College of Natural and Applied Sciences, University of Dar es Salaam, 2020 Sedimentology and Paleocurrent Study of the Early Triassic Rocks in the Ruhuhu Basin, SW Tanzania Audax Syprian Kiwango* and Diwakar Mishra Department of Geology, College of Earth Sciences and Engineering, The University of Dodoma, P. O. Box 259, Dodoma, Tanzania E-mail addresses: [email protected]; [email protected] *Corresponding author Received 14 November 2019, Revised 9 April 2020, Accepted 27 April 2020, Published June 2020 Abstract The sedimentary succession ranging in age from Permian to Early Triassic in Ruhuhu basin was subdivided into eight informal lithostratigraphic units, identified by the symbols from K1 to K8. Manda Formation (K8) belongs to Early Triassic age and comprises two Members, i.e., Lower Kingori Member and Upper Lifua Member (150-200 m thickness). The implications of present study relate to inter and intra basinal correlations which may provide regional depositional framework from a mass of local details. Present investigation connoting the lithofacies studies in conjunction with palaeocurrent and grain size analysis of the early Triassic strata aims at interpreting the depositional environment of Lifua Member. Based on the present study, five lithofacies have been identified, namely (i) Massive matrix supported paraconglomerate (Gmm), (ii) Massive sandstone (Sm), (iii) Parallel-horizontal laminated sandstone (Sh), (iv) Planar cross- bedded sandstone (Sp) and (v) Fine silt, mud and clay (Fl). Sandstone facies (Sm, Sh, and Sp) exhibit normal grading and unimodal palaeocurrent direction. Grain size analysis indicated that the sandstones were moderately sorted, finely skewed, mesokurtic and most of the grains were silty- sand.
    [Show full text]
  • PDF Available Here
    Edinburgh Research Explorer The sail-backed reptile Ctenosauriscus from the latest Early Triassic of Germany and the timing and biogeography of the early archosaur radiation Citation for published version: Butler, RJ, Brusatte, SL, Reich, M, Hornung, JJ, Nesbitt, SJ & Schoch, RR 2011, 'The sail-backed reptile Ctenosauriscus from the latest Early Triassic of Germany and the timing and biogeography of the early archosaur radiation', PLoS ONE, vol. 6, no. 10. https://doi.org/10.1371/journal.pone.0025693 Digital Object Identifier (DOI): 10.1371/journal.pone.0025693 Link: Link to publication record in Edinburgh Research Explorer Document Version: Publisher's PDF, also known as Version of record Published In: PLoS ONE Publisher Rights Statement: This is an Open-Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly cited. Made available through the Public Library of Science (2011) General rights Copyright for the publications made accessible via the Edinburgh Research Explorer is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policy The University of Edinburgh has made every reasonable effort to ensure that Edinburgh Research Explorer content complies with UK legislation. If you believe that the public display of this file breaches copyright please contact [email protected] providing details, and we will remove access to the work immediately and investigate your claim.
    [Show full text]
  • University of Birmingham the Earliest Bird-Line Archosaurs and The
    University of Birmingham The earliest bird-line archosaurs and the assembly of the dinosaur body plan Nesbitt, Sterling; Butler, Richard; Ezcurra, Martin; Barrett, Paul; Stocker, Michelle; Angielczyk, Kenneth; Smith, Roger; Sidor, Christian; Niedzwiedzki, Grzegorz; Sennikov, Andrey; Charig, Alan DOI: 10.1038/nature22037 License: None: All rights reserved Document Version Peer reviewed version Citation for published version (Harvard): Nesbitt, S, Butler, R, Ezcurra, M, Barrett, P, Stocker, M, Angielczyk, K, Smith, R, Sidor, C, Niedzwiedzki, G, Sennikov, A & Charig, A 2017, 'The earliest bird-line archosaurs and the assembly of the dinosaur body plan', Nature, vol. 544, no. 7651, pp. 484-487. https://doi.org/10.1038/nature22037 Link to publication on Research at Birmingham portal Publisher Rights Statement: Checked for eligibility: 03/03/2017. General rights Unless a licence is specified above, all rights (including copyright and moral rights) in this document are retained by the authors and/or the copyright holders. The express permission of the copyright holder must be obtained for any use of this material other than for purposes permitted by law. •Users may freely distribute the URL that is used to identify this publication. •Users may download and/or print one copy of the publication from the University of Birmingham research portal for the purpose of private study or non-commercial research. •User may use extracts from the document in line with the concept of ‘fair dealing’ under the Copyright, Designs and Patents Act 1988 (?) •Users may not further distribute the material nor use it for the purposes of commercial gain. Where a licence is displayed above, please note the terms and conditions of the licence govern your use of this document.
    [Show full text]
  • DINOSAUR SUCCESS in the TRIASSIC: a NONCOMPETITIVE ECOLOGICAL MODEL This Content Downloaded from 137.222.248.217 on Sat, 17
    VOLUME 58, No. 1 THE QUARTERLY REVIEW OF BIOLOGY MARCH 1983 DINOSAUR SUCCESS IN THE TRIASSIC: A NONCOMPETITIVE ECOLOGICAL MODEL MICHAEL J. BENTON University Museum, Parks Road, Oxford OX] 3PW, England, UK ABSTRACT The initial radiation of the dinosaurs in the Triassic period (about 200 million years ago) has been generally regarded as a result of successful competition with the previously dominant mammal- like reptiles. A detailed review of major terrestrial reptile faunas of the Permo- Triassic, including estimates of relative abundance, gives a different picture of the pattern of faunal replacements. Dinosaurs only appeared as dominant faunal elements in the latest Triassic after the disappear- ance of several groups qf mammal-like reptiles, thecondontians (ancestors of dinosaurs and other archosaurs), and rhynchosaurs (medium-sized herbivores). The concepts of differential survival ("competitive") and opportunistic ecological replacement of higher taxonomic categories are contrasted (the latter involves chance radiation to fill adaptive zones that are already empty), and they are applied to the fossil record. There is no evidence that either thecodontians or dinosaurs demonstrated their superiority over mammal-like reptiles in massive competitive take-overs. Thecodontians arose as medium-sized carnivores after the extinction of certain mammal-like reptiles (opportunism, latest Permian). Throughout most of the Triassic, the thecodontians shared carnivore adaptive zones with advanced mammal-like reptiles (cynodonts) until the latter became extinct (random processes, early to late Triassic). Among herbivores, the dicynodont mammal-like reptiles were largely replaced by diademodontoid mammal-like reptiles and rhynchosaurs (differential survival, middle to late Triassic). These groups then became extinct and dinosaurs replaced them and radiated rapidly (opportunism, latest Triassic).
    [Show full text]
  • Download Article (PDF)
    OCCASIONAL PAPER No. 251 Records of the Zoological Survey of India A Bibliography of Foss·' .. Reptilia of India T. K. Pal s. K. Ray B. Barik K. D. Saha ZOOLOGICAL SURVEY OF L DIA OCCASIONAL PAPER No. 251 RECORDS OF THE ZOOLOGICAL SURVEY OF INDIA A Bibliography of Fossil Reptilia of India T.K.PAL S. K. RAY B.BARIK K.D.SABA Zoological Survey of India, M Block, New Alipore, Kolkata-700 053, India. Edited by the Director, Zoological Survey of India, Kolkata Zoological Survey of India Kolkata CITATION Pal, T. K., Ray, S. K., Barik, B. and Saha, K. D. 2006. A Bibliography of Fossil, Reptilia of India. Rec. zool. Surv. India, Occ. Paper No. 251 : 1-47, (Published by the Director, Zool. Surv. India, Kolkata) Published : May, 2006 ISBN 81-8171-109-2 © Govt. of India, 2006 ALL RIGHTS RESERVED • No part of this publication may be reproduced stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without the prior permission of the publisher. • This book is sold subject to the condition that it shall not, by way of trade, be lent, resold hired out or otherwise disposed of without the publisher's consent, in an form of binding or cover other than that in which, it is published. • The correct price of this publication is the price printed on this page. Any revised price indicated by a rubber stamp or by a sticker or by any other means is incorrect and should be unacceptable. PRICE Indian Rs.
    [Show full text]
  • ON the PRINCIPLES of GLOBAL CORRELATION of the CONTINENTAL TRIASSIC on the TETRAPODS the Triassic Was a Time of Transition From
    Acta Palaeontologica Polonica Vol. 34, No. 2 pp. 149-173 Warszawa, 1989 V. G. OCHEV and M. A. SHISHKIN ON THE PRINCIPLES OF GLOBAL CORRELATION OF THE CONTINENTAL TRIASSIC ON THE TETRAPODS OCHEV, V. G. and SHISHKIN, M. A.: On the principles of global correlation af the continental Triassic on the tetsapods. Acta Palaeont. Polonica, 34, 2, 143--173, 1989. History of the Triassic land vertebrates comprises three successive global epoches referred to as proterosuchian, kannemeyeroid and dinosaur ones. The earliest and the middle epoches are typified by the regional faunal sequence of East Europe. The proterosuchian time spaas here the Neorhachitome and Paroto- suchus faunas, the former being directly correlated with the Induan-Lower Olenekian, and the latter with the Upper Olenekian (Spathian). The Eryosuchus and Mastodonsaurus faunas of the kannemeyeroid epoch in East Europe are Middle Triassic in age and correspond to the Muschelkalk and Lettenkohle respectively. An evidence is brought for contemporaneity of the protero- suchian-kannemeyeroid biotic replacement in Laurasia and Gondwana. This implies the Middle Triassic age of the Cynognathus Zone of South Africa and its equivalents in South America. The bulk of Lystrosausus fauna in Gondwana is suggested to range over the most of, or the whole, Early Triassic. K e y w 0 r d s: Triassic tetrapods, biotic epoches, correlation. V. G. Ochev, Saratov State University, Saratov, USSR; M. A. Shtshktn, PaUleontologtcal Institute, Academy of Sciences of the USSR, Profsoyuznaya, 123 Moscow, USSR. Received: December 1988. INTRODUCTION The Triassic was a time of transition from the late Palaeozoic (the- rapsid) to the true Mesozoic (archosaur) stage of the tetrapod faunal evolution.
    [Show full text]