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Evolutionary Patterns of Trilobites Across the End Ordovician Mass Extinction
Evolutionary Patterns of Trilobites Across the End Ordovician Mass Extinction by Curtis R. Congreve B.S., University of Rochester, 2006 M.S., University of Kansas, 2008 Submitted to the Department of Geology and the Faculty of the Graduate School of The University of Kansas in partial fulfillment on the requirements for the degree of Doctor of Philosophy 2012 Advisory Committee: ______________________________ Bruce Lieberman, Chair ______________________________ Paul Selden ______________________________ David Fowle ______________________________ Ed Wiley ______________________________ Xingong Li Defense Date: December 12, 2012 ii The Dissertation Committee for Curtis R. Congreve certifies that this is the approved Version of the following thesis: Evolutionary Patterns of Trilobites Across the End Ordovician Mass Extinction Advisory Committee: ______________________________ Bruce Lieberman, Chair ______________________________ Paul Selden ______________________________ David Fowle ______________________________ Ed Wiley ______________________________ Xingong Li Accepted: April 18, 2013 iii Abstract: The end Ordovician mass extinction is the second largest extinction event in the history or life and it is classically interpreted as being caused by a sudden and unstable icehouse during otherwise greenhouse conditions. The extinction occurred in two pulses, with a brief rise of a recovery fauna (Hirnantia fauna) between pulses. The extinction patterns of trilobites are studied in this thesis in order to better understand selectivity of the -
Zootaxa,Crustacean Classification
Zootaxa 1668: 313–325 (2007) ISSN 1175-5326 (print edition) www.mapress.com/zootaxa/ ZOOTAXA Copyright © 2007 · Magnolia Press ISSN 1175-5334 (online edition) Crustacean classification: on-going controversies and unresolved problems* GEOFF A. BOXSHALL Department of Zoology, The Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom E-mail: [email protected] *In: Zhang, Z.-Q. & Shear, W.A. (Eds) (2007) Linnaeus Tercentenary: Progress in Invertebrate Taxonomy. Zootaxa, 1668, 1–766. Table of contents Abstract . 313 Introduction . 313 Treatment of parasitic Crustacea . 315 Affinities of the Remipedia . 316 Validity of the Entomostraca . 318 Exopodites and epipodites . 319 Using of larval characters in estimating phylogenetic relationships . 320 Fossils and the crustacean stem lineage . 321 Acknowledgements . 322 References . 322 Abstract The journey from Linnaeus’s original treatment to modern crustacean systematics is briefly characterised. Progress in our understanding of phylogenetic relationships within the Crustacea is linked to continuing discoveries of new taxa, to advances in theory and to improvements in methodology. Six themes are discussed that serve to illustrate some of the major on-going controversies and unresolved problems in the field as well as to illustrate changes that have taken place since the time of Linnaeus. These themes are: 1. the treatment of parasitic Crustacea, 2. the affinities of the Remipedia, 3. the validity of the Entomostraca, 4. exopodites and epipodites, 5. using larval characters in estimating phylogenetic rela- tionships, and 6. fossils and the crustacean stem-lineage. It is concluded that the development of the stem lineage concept for the Crustacea has been dominated by consideration of taxa known only from larval or immature stages. -
Ediakara Ediacara
Ediakara Stratotyyppi ja elämän varhaiskehityksen problematiikka Ediacara Stratotype and the problematics of the Metazoan origins ANNA HAAPANIEMI Abstract tavasti viimeaikoina. Tämä on saattanut olla yksi niistä syistä, miksi aikakaudesta usein käytetty nimi The new geological period Ediacara has been ”Vendi” korvattiin nyt Ediakaralla. Mutta samalla discussed vividly ever since its formal ratification kun kambrikautisten fossiilien joukosta on löytynyt in 2004. Although Ediacara is a considerable leap merkkejä ediakaraeliöstöstä, niin nyt myös ediaka- in the construction of an international geological rakautisista kerrostumista on raportoitu löydetyn timetable, it is also connected to several theories entuudestaan tunnettuja kambrikautisia eläimiä. and concepts central to the geological community, Nämä löydöt siirtäisivät kiistattomasti monisoluis- but sometimes little understood. The Vendobionta ten kehityksen prekambriin. Näin ollen komplek- theory created by Seilacher is now rivalled by sisen elämän synnyn tutkimuksen painopiste on the “Ediacaran survivors” –hypothesis of Con- siirtynyt kambrikauden radiaation syistä ediakara- way Morris. Supporting evidence of Ediacarans kauden alkuun. Eliöstön mahdollinen kehittyminen in Cambrian strata seems to be piling up, but at Rodinian hajoamisen jälkeisten jäätiköiden keskelle the same time Cambrian animals appear to have on problemaattinen; jäätiköitymiskauden on arvioi- their origin deep in ediacaran times. Thus, the tu olleen tuona aikana epätavallisen laaja. Mikäli focus of current research has partly shifted from elämän kehittyminen on ollut mahdollista, on voi- the causes of Cambrian radiation to the beginning makas valintapaine ja isolaatio saattanut olla radiaa- of Ediacaran. However, the first appearance of the tion taustalla. Vaihtoehtoisesti kyseessä on saattanut biota in the glacial conditions of the post-Rodinian olla ’punctuated equilibrium’ -teorian mukainen world is problematic; the glacial extent has been evoluutionopeuden kiihtyminen; viimeisimmän jää- estimated unusually large. -
An Exceptionally Preserved Arthropod Cardiovascular System from the Early Cambrian
ARTICLE Received 20 Dec 2013 | Accepted 4 Mar 2014 | Published 7 Apr 2014 DOI: 10.1038/ncomms4560 An exceptionally preserved arthropod cardiovascular system from the early Cambrian Xiaoya Ma1,2, Peiyun Cong1, Xianguang Hou1, Gregory D. Edgecombe2 & Nicholas J. Strausfeld3 The assumption that amongst internal organs of early arthropods only the digestive system withstands fossilization is challenged by the identification of brain and ganglia in early Cambrian fuxianhuiids and megacheirans from southwest China. Here we document in the 520-million-year-old Chengjiang arthropod Fuxianhuia protensa an exceptionally preserved bilaterally symmetrical organ system corresponding to the vascular system of extant arthropods. Preserved primarily as carbon, this system includes a broad dorsal vessel extending through the thorax to the brain where anastomosing branches overlap brain seg- ments and supply the eyes and antennae. The dorsal vessel provides segmentally paired branches to lateral vessels, an arthropod ground pattern character, and extends into the anterior part of the abdomen. The addition of its vascular system to documented digestive and nervous systems resolves the internal organization of F. protensa as the most completely understood of any Cambrian arthropod, emphasizing complexity that had evolved by the early Cambrian. 1 Yunnan Key Laboratory for Palaeobiology, Yunnan University, Kunming 650091, China. 2 Department of Earth Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD, UK. 3 Department of Neuroscience and Center for Insect Science, University of Arizona, Tucson, Arizona 85721, USA. Correspondence and requests for materials should be addressed to X.H. (email: [email protected]) or to N.J.S. (email: fl[email protected]). -
001-012 Primeras Páginas
PUBLICACIONES DEL INSTITUTO GEOLÓGICO Y MINERO DE ESPAÑA Serie: CUADERNOS DEL MUSEO GEOMINERO. Nº 9 ADVANCES IN TRILOBITE RESEARCH ADVANCES IN TRILOBITE RESEARCH IN ADVANCES ADVANCES IN TRILOBITE RESEARCH IN ADVANCES planeta tierra Editors: I. Rábano, R. Gozalo and Ciencias de la Tierra para la Sociedad D. García-Bellido 9 788478 407590 MINISTERIO MINISTERIO DE CIENCIA DE CIENCIA E INNOVACIÓN E INNOVACIÓN ADVANCES IN TRILOBITE RESEARCH Editors: I. Rábano, R. Gozalo and D. García-Bellido Instituto Geológico y Minero de España Madrid, 2008 Serie: CUADERNOS DEL MUSEO GEOMINERO, Nº 9 INTERNATIONAL TRILOBITE CONFERENCE (4. 2008. Toledo) Advances in trilobite research: Fourth International Trilobite Conference, Toledo, June,16-24, 2008 / I. Rábano, R. Gozalo and D. García-Bellido, eds.- Madrid: Instituto Geológico y Minero de España, 2008. 448 pgs; ils; 24 cm .- (Cuadernos del Museo Geominero; 9) ISBN 978-84-7840-759-0 1. Fauna trilobites. 2. Congreso. I. Instituto Geológico y Minero de España, ed. II. Rábano,I., ed. III Gozalo, R., ed. IV. García-Bellido, D., ed. 562 All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system now known or to be invented, without permission in writing from the publisher. References to this volume: It is suggested that either of the following alternatives should be used for future bibliographic references to the whole or part of this volume: Rábano, I., Gozalo, R. and García-Bellido, D. (eds.) 2008. Advances in trilobite research. Cuadernos del Museo Geominero, 9. -
The Cambrian Explosion: a Big Bang in the Evolution of Animals
The Cambrian Explosion A Big Bang in the Evolution of Animals Very suddenly, and at about the same horizon the world over, life showed up in the rocks with a bang. For most of Earth’s early history, there simply was no fossil record. Only recently have we come to discover otherwise: Life is virtually as old as the planet itself, and even the most ancient sedimentary rocks have yielded fossilized remains of primitive forms of life. NILES ELDREDGE, LIFE PULSE, EPISODES FROM THE STORY OF THE FOSSIL RECORD The Cambrian Explosion: A Big Bang in the Evolution of Animals Our home planet coalesced into a sphere about four-and-a-half-billion years ago, acquired water and carbon about four billion years ago, and less than a billion years later, according to microscopic fossils, organic cells began to show up in that inert matter. Single-celled life had begun. Single cells dominated life on the planet for billions of years before multicellular animals appeared. Fossils from 635,000 million years ago reveal fats that today are only produced by sponges. These biomarkers may be the earliest evidence of multi-cellular animals. Soon after we can see the shadowy impressions of more complex fans and jellies and things with no names that show that animal life was in an experimental phase (called the Ediacran period). Then suddenly, in the relatively short span of about twenty million years (given the usual pace of geologic time), life exploded in a radiation of abundance and diversity that contained the body plans of almost all the animals we know today. -
The Evolution of Trilobite Body Patterning
ANRV309-EA35-14 ARI 20 March 2007 15:54 The Evolution of Trilobite Body Patterning Nigel C. Hughes Department of Earth Sciences, University of California, Riverside, California 92521; email: [email protected] Annu. Rev. Earth Planet. Sci. 2007. 35:401–34 Key Words First published online as a Review in Advance on Trilobita, trilobitomorph, segmentation, Cambrian, Ordovician, January 29, 2007 diversification, body plan The Annual Review of Earth and Planetary Sciences is online at earth.annualreviews.org Abstract This article’s doi: The good fossil record of trilobite exoskeletal anatomy and on- 10.1146/annurev.earth.35.031306.140258 togeny, coupled with information on their nonbiomineralized tis- Copyright c 2007 by Annual Reviews. sues, permits analysis of how the trilobite body was organized and All rights reserved developed, and the various evolutionary modifications of such pat- 0084-6597/07/0530-0401$20.00 terning within the group. In several respects trilobite development and form appears comparable with that which may have charac- terized the ancestor of most or all euarthropods, giving studies of trilobite body organization special relevance in the light of recent advances in the understanding of arthropod evolution and devel- opment. The Cambrian diversification of trilobites displayed mod- Annu. Rev. Earth Planet. Sci. 2007.35:401-434. Downloaded from arjournals.annualreviews.org ifications in the patterning of the trunk region comparable with by UNIVERSITY OF CALIFORNIA - RIVERSIDE LIBRARY on 05/02/07. For personal use only. those seen among the closest relatives of Trilobita. In contrast, the Ordovician diversification of trilobites, although contributing greatly to the overall diversity within the clade, did so within a nar- rower range of trunk conditions. -
The Impact of Deep-Tier Burrow Systems in Sediment Mixing and Ecosystem Engineering in Early Cambrian Carbonate Settings
www.nature.com/scientificreports OPEN The impact of deep-tier burrow systems in sediment mixing and ecosystem engineering in early Received: 17 November 2016 Accepted: 02 March 2017 Cambrian carbonate settings Published: 04 April 2017 Li-Jun Zhang1, Yong-An Qi1, Luis A. Buatois2, M. Gabriela Mángano2, Yao Meng1 & Da Li1 Bioturbation plays a substantial role in sediment oxygen concentration, chemical cycling, regeneration of nutrients, microbial activity, and the rate of organic matter decomposition in modern oceans. In addition, bioturbators are ecosystem engineers which promote the presence of some organisms, while precluding others. However, the impact of bioturbation in deep time remains controversial and limited sediment mixing has been indicated for early Paleozoic seas. Our understanding of the actual impact of bioturbation early in the Phanerozoic has been hampered by the lack of detailed analysis of the functional significance of specific burrow architectures. Integration of ichnologic and sedimentologic evidence from North China shows that deep-tier Thalassinoides mazes occur in lower Cambrian nearshore carbonate sediments, leading to intense disruption of the primary fabric. Comparison with modern studies suggest that some of the effects of this style of Cambrian bioturbation may have included promotion of nitrogen and ammonium fluxes across the sediment-water interface, average deepening of the redox discontinuity surface, expansion of aerobic bacteria, and increase in the rate of organic matter decomposition and the regeneration of nutrients. Our study suggests that early Cambrian sediment mixing in carbonate settings may have been more significant than assumed in previous models. Bioturbation, involving both particle and solute transport within burrows, into the surrounding sediment and across the sediment-water interface, is one of the most important factors in affecting oxygen concentration in the sediment, chemical cycling, regeneration of nutrients, microbial activity and the rate of organic matter decom- position in modern oceans1–3. -
Th TRILO the Back to the Past Museum Guide to TRILO BITES
With regard to human interest in fossils, trilobites may rank second only to dinosaurs. Having studied trilobites most of my life, the English version of The Back to the Past Museum Guide to TRILOBITES by Enrico Bonino and Carlo Kier is a pleasant treat. I am captivated by the abundant color images of more than 600 diverse species of trilobites, mostly from the authors’ own collections. Carlo Kier The Back to the Past Museum Guide to Specimens amply represent famous trilobite localities around the world and typify forms from most of the Enrico Bonino Enrico 250-million-year history of trilobites. Numerous specimens are masterpieces of modern professional preparation. Richard A. Robison Professor Emeritus University of Kansas TRILOBITES Enrico Bonino was born in the Province of Bergamo in 1966 and received his degree in Geology from the Depart- ment of Earth Sciences at the University of Genoa. He currently lives in Belgium where he works as a cartographer specialized in the use of satellite imaging and geographic information systems (GIS). His proficiency in the use of digital-image processing, a healthy dose of artistic talent, and a good knowledge of desktop publishing software have provided him with the skills he needed to create graphics, including dozens of posters and illustrations, for all of the displays at the Back to the Past Museum in Cancún. In addition to his passion for trilobites, Enrico is particularly inter- TRILOBITES ested in the life forms that developed during the Precambrian. Carlo Kier was born in Milan in 1961. He holds a degree in law and is currently the director of the Azul Hotel chain. -
The Role of Chironomidae in Separating Naturally Poor from Disturbed Communities
From taxonomy to multiple-trait bioassessment: the role of Chironomidae in separating naturally poor from disturbed communities Da taxonomia à abordagem baseada nos multiatributos dos taxa: função dos Chironomidae na separação de comunidades naturalmente pobres das antropogenicamente perturbadas Sónia Raquel Quinás Serra Tese de doutoramento em Biociências, ramo de especialização Ecologia de Bacias Hidrográficas, orientada pela Doutora Maria João Feio, pelo Doutor Manuel Augusto Simões Graça e pelo Doutor Sylvain Dolédec e apresentada ao Departamento de Ciências da Vida da Faculdade de Ciências e Tecnologia da Universidade de Coimbra. Agosto de 2016 This thesis was made under the Agreement for joint supervision of doctoral studies leading to the award of a dual doctoral degree. This agreement was celebrated between partner institutions from two countries (Portugal and France) and the Ph.D. student. The two Universities involved were: And This thesis was supported by: Portuguese Foundation for Science and Technology (FCT), financing program: ‘Programa Operacional Potencial Humano/Fundo Social Europeu’ (POPH/FSE): through an individual scholarship for the PhD student with reference: SFRH/BD/80188/2011 And MARE-UC – Marine and Environmental Sciences Centre. University of Coimbra, Portugal: CNRS, UMR 5023 - LEHNA, Laboratoire d'Ecologie des Hydrosystèmes Naturels et Anthropisés, University Lyon1, France: Aos meus amados pais, sempre os melhores e mais dedicados amigos Table of contents: ABSTRACT ..................................................................................................................... -
Arthropod Origins
Bulletin of Geosciences, Vol. 78, No. 4, 323–334, 2003 © Czech Geological Survey, ISSN 1214-1119 Arthropod origins Jan Bergström 1 – Hou Xian-Guang 2 1 Swedish Museum of Nature History, Box 50007, S-104 05 Stockholm, Sweden. E-mail: [email protected] 2 Yunnan University, Yunnan Research Center for Chengjiang Biota, Kunming 650091, Peoples’ Republic of China. E-mail: [email protected] Abstract. Reconsideration of the position of trilobite-like arthropods leads to an idea of the last shared ancestor of known (eu)arthropods. The ancestry and morphological evolution is traced back from this form to a hypothetical ciliated and pseudosegmented slug-like ancestor. Evolution logically passed through a lobopodian stage. Extant onychophorans, Cambrian xenusians, and perhaps anomalocaridids with their kin (the Dinocaridida) may represent probable offshoots on the way. As such, these groups are highly derived and not ancestral to the arthropods. Results of molecular studies indicate a rela- tionship to moulting worms, which at first could seem to be in conflict with what was just said. However, if this is correct, the arthropod and moulting worm lineages must have diverged when some “coelomate” features such as specific vascular and neural systems were still present. The moulting worms would therefore have lost such characters, either only once or several times. Key words: arthropod origins, Anomalocaris, Tardigrada, Cambrian arthropods, Cycloneuralia, trilobitomorphs, eye ridge Introduction immediate ancestors might have looked like, and what they could not have been like. For instance, if the first arthro- Most of our important information on early arthropods co- pods were completely primitive in certain respects, they mes from such deposits as the Lower Cambrian Chengji- cannot be traced back to animals that are highly derived in ang beds, the Middle Cambrian Burgess Shale, and the Up- these respects. -
A Revision of the Late Ordovician Marrellomorph Arthropod Furca Bohemica from Czech Republic
A revision of the Late Ordovician marrellomorph arthropod Furca bohemica from Czech Republic Štĕpán Rak, Javier Ortega-Hernández, and David A. Legg Acta Palaeontologica Polonica 58 (3), 2012: 615-628 doi: http://dx.doi.org/10.4202/app.2011.0038 The enigmatic marrellomorph arthropod Furca bohemica from the Upper Ordovician Letná Formation, is redescribed. Based on existing museum specimens and new material collected from the southern slope of Ostrý Hill (Beroun, Czech Republic), the morphology and taphonomy of F. bohemica is reappraised and expanded to produce a new anatomical interpretation. The previously distinct taxa F. pilosa and Furca sp., are synonymised with F. bohemica, the latter being represented by a tapho−series in which decay has obscured some of the diagnostic features. A cladistic analysis indicates close affinities between F. bohemica and the Hunsrück Slate marrellomorph Mimetaster hexagonalis, together forming the Family Mimetasteridae, contrary to previous models for marrellomorph internal relationships. As with other representatives of the group, the overall anatomy of F. bohemica is consistent with a benthic, or possibly nektobenthic, mode of life. The depositional setting of the Letná Formation indicates that F. bohemica inhabited a shallow marine environment, distinguishing it palaeoecologically from all other known marrellomorphs, which have been reported from the continental shelf. Key words: Arthropoda, Marrella, Mimetaster, shallow marine environment, Letná Formation, Barrandian, Ordovician, Ostrý Hill, Czech Republic. Štĕpán Rak [[email protected]], Charles University, Institute of Geology and Palaeontology, Albertov 6, 128 43, Prague 2, Czech Republic; Javier Ortega-Hernández [[email protected]], Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK; David A.