DOCSLIB.ORG

Sirenians and Sirens

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Sirenians and Sirens Foreword Sea cows are not closely related to cows. This common name stuck because they feed almost exclusively on sea grasses or other aquatic vegetation. In scientic literature, sea cows are often referred to as “sirenians.” Both terms are used interchangeably. There are two groups of extant (currently living) sea cows: the manatees of the Atlantic Ocean, and the dugongs of the Indian and Pacic Oceans. Although manatees and dugongs are both sea cows, and sirenians, they are quite different in many respects. From time to time, the fossilized bones of Dr. Daryl Domning examines a life-size skeletal reconstruction of the fteen-million-year-old sea cows erode from the fty million-year-old sea cow, Pezosiren portelli, from Jamaica. This four- legged sea cow was described and named by Dr. Daryl Domning in 2001. cliffs along the western shore of the Chesapeake The unpigmented [grey] bones have not yet been found as fossils. They Bay in Maryland. That sea cows were regular prehistoric were sculpted to complete this skeletal mount. © Calvert Marine Museum. inhabitants of this area tweaked my interest in this group of marine mammals. That sea cows were the inspiration Funding provided by: The Board of Editorial work: Paul Berry, Dr. Daryl for the origin of some mermaid myths kindled the interest of County Commissioners, the citizens of Domning, Karen Stone, Pat Fink Calvert County, Maryland, and Clarissa and Permission for use of gures on pages 28-30: other exhibit committee members and essentially guaranteed Lincoln Dryden Endowment for Meri Lao (www.sirenalatina.com) from her that I would be able to pursue research into the origin and Paleontology at the Calvert Marine Museum book, Sirens, Symbols of Seduction . 1998. Park Director: C. Douglass Alves Jr. Street Press. Rochester, VT. 186. evolution of sea cows and mermaids for the purpose of Text and Art Consultant: D r. Daryl Permission for use of gures on pages 19-22: generating an exhibit for the Calvert Marine Museum. Domning (Howard University) Zoological Society of London Written by: D r. Stephen Godfrey Mark McCloud at Curtis Brown Ltd. for The recent discovery of Pezosiren portelli , fty-million-year-old Exhibit Design: Jimmy Langley permission to cite the poem by Ogden Nash. four-legged fossil “sea cows” from Jamaica, was one of the driving Art: Tim Scheirer Marine Mammal Pathobiology Graphics: Teresa Baird Laboratory (Mr. Alex M. Costidis) of the forces behind compiling this guidebook. In addition to this, Sea cow life model: Skip Edwards, Florida Marine Research Institute. having generated so many interesting images for the exhibit, it D r. Stephen Godfrey The following individuals also had a hand in Book Design: Edie Fleshood the success of this endeavor (listed alphabetically): seemed a shame not to make an attempt to disseminate them more Photo Credits: Dr. Daryl Domning, Teresa Constance Barut-Rankin, Maureen widely. Consequently, although this exhibit guide is based on the Baird, Diana Magor, Florida Power and Baughman, Paul Darby, Robert Hurry, Monte exhibit “Sirens and Sirenians,” it is a stand-alone summary of Light, Doug Perrine (www.seapics.com), Newman, Laura O’Neill, Richard Rogers, D r. Stephen Godfrey Patricia Sopp, Ken Wease, Scott Werts, Lee our present knowledge on the origin and evolution Ann Wright, Debra Yorty, Tom and Sandy of both sirenians and sirens. Younger Stephen Godfrey Ph.D., Curator of Paleontology Calvert Marine Museum, Solomons, Maryland © Copyright Calvert Marine Museum, 2002 Introduction Living sea cows (sirenians) are a group of aquatic, mostly herbivorous (plant-eating) mammals. Like other mammals, they all have at least some hair on their bodies and females give birth to babies that drink their mothers’ milk. Although sea cows are relatively rare creatures today, they were much more common and widespread in the past, especially during the Miocene epoch (23.8-5.3 million years ago). Sirenian fossils have been collected in Europe and North America since the earliest days of vertebrate paleontology, but their fossil record is still spotty. Without a doubt, other extinct sea cow species will be discovered as paleontologists continue their search. The intent of this work is to give you an application of the remarkable history and biology of these unique animals, and the curious relationship they share with mermaids. A dugong cruising the shallow waters of the western Pacific Ocean. © Doug Perrine/Seapics.com. THE ORIGIN AND DIVERSITY OF SEA COWS THROUGH The First Sea Cows Present-day sea cows look like fat, stubby-faced dolphins(a group to which they are not closely related). They have very rounded but streamlined bodies, flipper- like front arms, no hind legs, and a powerfulhorizontal tail fin for swimming. However, sirenians have not always had the features that allow them to spend all their lives in water. The oldest known ones, A skeletal restoration of Pezosiren portelli. Very few foot or tail bones have been found to date. like Pezosiren portelli Domning 2001 (and other members of the familyProrastomidae), that lived about fiVy million years ago, did not have streamlined bodies, front flippers, or a tail fin. Instead, these pig-sizedcreatures had short but fully functional front and hind legs for walking around on land (See figures at right). Like One possible life restoration of Pezosiren portelli. Here, Pezosiren is shown modern sea cows, however, these ancient creatures had standing on its toes (a condition anatomists describe as digitigrade), much heavy bones that helped to counteract the buoyant effects like a modern-day pig; however, it is also possible that its foot posture was of their large lungs, suggesting that they spent much of more otter-like or “at-footed” (i.e., plantigrade). their time, hippo-like, sloshing about in water. 4 Sirenians and Sirens: Seacows and Mermaids fiftyfifty m illionyears ago ... A life restoration of Pezosiren portelli as it may have appeared fty million years ago in its tropical habitat near present-day Seven Rivers, Jamaica. Sea Cow Relatives Sea cows are grouped with elephants and desmostylians(an entirely extinct group of hippo-like behemoths) in a larger assemblage of mammals known as the Tethytheria, meaning “Beasts from the Tethys Sea.” Although living sea cows and elephants are about as different as two mammals can appear to be, the oldest-known elephant-like creatures and sea cows were similar and are presumed to share a common ancestor which lived THE ORIGIN AND DIVERSITY OF SEA COWS THROUGH P rorastomus sirenoides The first evidence of the oldest and most primitive known sea cows dates from 1855, when paleontologist Sir Richard Owen described a fiVy-million-year-old sea cow skullcollected from Eocene sediments from Jamaica and gave it the name P rorastomus sirenoides. Unfortunately, very lile of the rest of the skeleton was known, so not much could be said about its ability to move about in water or on land. The discovery, by Dr. Daryl Domning and Roger Portell,of the closely related Pezosiren portelli that was able to walkabout on land or swim in the water, would strongly suggest that P rorastomus sirenoides was similarly endowed. A skull drawing of Prorastomus sirenoides in a leV lateral view. Scale bar P rotosiren, another Eocene sirenian, also had complete hind legs. However, its legs were proportionately shorter than those of Pezosiren and were in all likelihood incapable of liVing the belly of this creature off the ground for any length of time. Consequently, this sirenian was probably confined to the water. By the end of the Eocene, thirty-eight million years ago, sirenians like Eosiren had become fully aquatic, displaying a streamlined body and other specialized aquatic features. These aquatic sea cows, the early dugongids, had stubby (vestigial) flipper-like hind legs, if any. A life sketch of the seal-likeProtosire n. Sirenians and Sirens: Seacows and Mermaids 7 The diversity of sirenian genera through time based on fossil nds. Imagine how little we would know about sea cow evolution if their fossilized bones had never been found! WHAT MAKES A SEA COW A SEA COW? If the oldest extinct sea cows (the prorastomids)did not look much like livingsea cows, why do we call them “sea cows”? What is it about an animal that makes it a TYPICAL MAMMAL RIB sea cow? Scientists group plants and animals together (ATLANTIC BOTTLENOSE SLENDER SHAFT based on the clustering of unique features. For example, mammals are a unique group of animals that have hair and the females produce milk to feed their babies. Sea cows are mammals,distinguished from all others because some of the bones in their skeleton are greatly thickened (a condition known as “pachyostosis”),and these bones are much heavier than normal ones (a condition known as “osteosclerosis”). Fossilized MARROW CAVITY prorastomid bones are also both pachyostotic and osteosclerotic. In addition to which, these most ancient terrestrial sea cows exhibit other hallmarksthat evidence their membership in the sea cow clan. TYPICAL SEA COW RIB Work for Young Paleontologists (METAXYTHERIUM PACHYOSTOTIC BONE (SWOLLEN SHAFT) Will our understandingof the origin and evolution of sea cows change? Certainly, as more fossil sirenians are unearthed! Even though paleontologistshave been finding and describing extinct sea cows for almost two hundred years, many more prehistoric sea cow species remain to be discovered, particularly in the Southern OSTEOSCLEROTIC BONE Hemisphere and around the Indian Ocean. Future (NO MARROW CAVITY) fossil finds will give us a more complex but fuller understanding of the history of these creatures. Sirenians and Sirens: Seacows and Mermaids 9 A Typical Miocene Sea Cow: Metaxytherium crataegense No sea cow species has lived throughout this group’s fiVy-million-year history. Different kinds have lived at different times. More species of sea cows lived during the Miocene epoch than at any other time.
Load more

Recommended publications
  • “Halitherium” Cristolii Fitzinger, 1842 (Mammalia, Sirenia) from the Late Oligocene of Austria, with the Description of a New Genus
    European Journal of Taxonomy 256: 1–32 ISSN 2118-9773 http://dx.doi.org/10.5852/ejt.2016.256 www.europeanjournaloftaxonomy.eu 2016 · Voss M. et al. This work is licensed under a Creative Commons Attribution 3.0 License. Research article urn:lsid:zoobank.org:pub:43130F90-D802-4B65-BC6D-E3815A951C09 A taxonomic and morphological re-evaluation of “Halitherium” cristolii Fitzinger, 1842 (Mammalia, Sirenia) from the late Oligocene of Austria, with the description of a new genus Manja VOSS 1 ,*, Björn BERNING 2 & Erich REITER 3 1 Museum für Naturkunde – Leibniz Institute for Evolution and Biodiversity Science, Invalidenstraße 43, 10115 Berlin, Germany. 2 Upper Austrian State Museum, Geoscience Collections, Welser Straße 20, 4060 Leonding, Austria. 3 Institut für Chemische Technologie Anorganischer Stoffe, Johannes Kepler Universität Linz, Altenberger Straße 69, 4040 Linz, Austria. * Corresponding author: [email protected] 2 Email: [email protected] 3 Email: [email protected] 1 urn:lsid:zoobank.org:author:5B55FBFF-7871-431A-AE33-91A96FD4DD39 2 urn:lsid:zoobank.org:author:30D7D0DB-F379-4006-B727-E75A0720BD93 3 urn:lsid:zoobank.org:author:EA57128E-C88B-4A46-8134-0DF048567442 Abstract. The fossil sirenian material from the upper Oligocene Linz Sands of Upper Austria is reviewed and re-described in detail following a recent approach on the invalidity of the genus Halitherium Kaup, 1838. This morphological study provides the fi rst evidence for the synonymy of “Halitherium” cristolii Fitzinger 1842, “H.” abeli Spillmann, 1959 and “H.” pergense (Toula, 1899), supporting the hypothesis that only a single species inhabited the late Oligocene shores of present-day Upper Austria.
    [Show full text]
  • Contributions from the Museum of Paleontology the University of Michigan
    CONTRIBUTIONS FROM THE MUSEUM OF PALEONTOLOGY THE UNIVERSITY OF MICHIGAN VOL. 29.. No. 3. PP. 69-87 November 30. 1994 PROTOSIREN SMITHAE, NEW SPECIES (MAMMALIA, SIRENIA), FROM THE LATE MIDDLE EOCENE OF WADI HITAN, EGYPT BY DARYL P. DOMNING AND PHILIP D. GINGERICH MUSEUM OF PALEONTOLOGY THE UNIVERSITY OF MICHIGAN ANN ARBOR CONTRIBUTIONS FROM THE MUSEUM OF PALEONTOLOGY Philip D. Gingerich, Director This series of contributions from the Museum of Paleontology is a medium for publication of papers based chiefly on collections in the Museum. When the number of pages issued is sufficient to make a volume, a title page and a table of contents will be sent to libraries on the mailing list, and to individuals on request. A list of the separate issues may also be obtained by request. Correspondence should be directed to the Museum of Paleontology, The University of Michigan, Ann Arbor, Michigan 48 109-1079. VOLS. 2-29. Parts of volumes may be obtained if available. Price lists are available upon inquiry. PROTOSIREN SMITHAE, NEW SPECIES (MAMMALIA, SIRENIA), FROM THE LATE MIDDLE EOCENE OF WADI KITAN, EGYPT Abstract-Protosiren smithae is a new protosirenid sirenian described on the basis of associated cranial and postcranial material from the late middle Eocene (latest Bartonian) Gehannam Formation of Wadi Hitan (Zeuglodon Valley), Fayum Province, Egypt. The new species is similar to Protosiren fraasi Abel, 1907, from the earlier middle Eocene (Lutetian) of Egypt, but it is younger geologically and more derived morphologically. P. smithae is probably a direct descendant of P. fraasi. The postcranial skeleton of P. imithae- includes well-developed hindlimbs, which suggest some lingering amphibious tendencies in this otherwise aquatically-adapted primitive sea cow.
    [Show full text]
  • Classification of Mammals 61
    © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FORCHAPTER SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION Classification © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC 4 NOT FORof SALE MammalsOR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC © Jones & Bartlett Learning, LLC NOT FOR SALE OR DISTRIBUTION NOT FOR SALE OR DISTRIBUTION © Jones & Bartlett Learning, LLC. NOT FOR SALE OR DISTRIBUTION. 2ND PAGES 9781284032093_CH04_0060.indd 60 8/28/13 12:08 PM CHAPTER 4: Classification of Mammals 61 © Jones Despite& Bartlett their Learning,remarkable success, LLC mammals are much less© Jones stress & onBartlett the taxonomic Learning, aspect LLCof mammalogy, but rather as diverse than are most invertebrate groups. This is probably an attempt to provide students with sufficient information NOT FOR SALE OR DISTRIBUTION NOT FORattributable SALE OR to theirDISTRIBUTION far greater individual size, to the high on the various kinds of mammals to make the subsequent energy requirements of endothermy, and thus to the inabil- discussions of mammalian biology meaningful.
    [Show full text]
  • MARINE MAMMALS, EXTINCTIONS of Glenn R
    MARINE MAMMALS, EXTINCTIONS OF Glenn R. VanBlaricom,* Leah R. Gerber,† and Robert L. Brownell, Jr.‡ *U.S. Geological Survey and University of Washington, †University of California, Santa Barbara, and ‡National Marine Fisheries Service I. Introduction principal source for taxonomic nomenclature, includ- II. Patterns and Case Studies of Extinction in ing common names, is the recent review of Rice (1998). Marine Mammals The order Cetacea includes whales, dolphins, and III. Discussion porpoises (Table I). The ‘‘pinnipedia’’ is a group of species in three families in the mammalian order Carni- vora (Table I). The pinnipeds include the seals, fur seals, sea lions, and walrus. The term pinnipedia is no I. INTRODUCTION longer recognized formally by marine mammal taxono- mists, but it continues to appear in the systematic ver- A. Taxonomic Definition of nacular as a matter of tradition and convenience. The order Sirenia includes the extant manatees and dugong ‘‘Marine Mammals’’ and the extinct Steller’s sea cow (Table I). The order The marine mammals include one extinct order and Desmostylia is the only recognized order of marine three major extant taxa that were or are fully aquatic, mammals to become entirely extinct. in most cases occurring entirely in the marine habitats Two largely terrestrial families of the order Carnivora of the major ocean basins and associated coastal seas also include species recognized as marine mammals and estuaries. In addition, a few species of largely terres- (Table I). Sea otters and chungungos (family Mustel- trial taxa are currently regarded as marine mammals. idae) live entirely or primarily in marine habitats. Polar We consider 127 recent mammal species in total to bears (family Ursidae) also spend a significant propor- be marine mammals for purposes of this review.
    [Show full text]
  • West Indian Manatee (Trichechus Manatus) Habitat Characterization Using Side-Scan Sonar
    Andrews University Digital Commons @ Andrews University Master's Theses Graduate Research 2017 West Indian Manatee (Trichechus Manatus) Habitat Characterization Using Side-Scan Sonar Mindy J. McLarty Andrews University, [email protected] Follow this and additional works at: https://digitalcommons.andrews.edu/theses Part of the Biology Commons Recommended Citation McLarty, Mindy J., "West Indian Manatee (Trichechus Manatus) Habitat Characterization Using Side-Scan Sonar" (2017). Master's Theses. 98. https://digitalcommons.andrews.edu/theses/98 This Thesis is brought to you for free and open access by the Graduate Research at Digital Commons @ Andrews University. It has been accepted for inclusion in Master's Theses by an authorized administrator of Digital Commons @ Andrews University. For more information, please contact [email protected]. ABSTRACT WEST INDIAN MANATEE (TRICHECHUS MANATUS) HABITAT CHARACTERIZATION USING SIDE-SCAN SONAR by Mindy J. McLarty Chair: Daniel Gonzalez-Socoloske ABSTRACT OF GRADUATE STUDENT RESEARCH Thesis Andrews University School of Arts and Sciences Title: WEST INDIAN MANATEE (TRICHECHUS MANATUS) HABITAT CHARACTERIZATION USING SIDE-SCAN SONAR Name of researcher: Mindy J. McLarty Name and degree of faculty chair: Daniel Gonzalez-Socoloske, Ph.D. Date completed: April 2017 In this study, the reliability of low cost side-scan sonar to accurately identify soft substrates such as grass and mud was tested. Benthic substrates can be hard to classify from the surface, necessitating an alternative survey approach. A total area of 11.5 km2 was surveyed with the sonar in a large, brackish mangrove lagoon system. Individual points were ground-truthed for comparison with the sonar recordings to provide a measure of accuracy.
    [Show full text]
  • Download Full Article in PDF Format
    A new marine vertebrate assemblage from the Late Neogene Purisima Formation in Central California, part II: Pinnipeds and Cetaceans Robert W. BOESSENECKER Department of Geology, University of Otago, 360 Leith Walk, P.O. Box 56, Dunedin, 9054 (New Zealand) and Department of Earth Sciences, Montana State University 200 Traphagen Hall, Bozeman, MT, 59715 (USA) and University of California Museum of Paleontology 1101 Valley Life Sciences Building, Berkeley, CA, 94720 (USA) [email protected] Boessenecker R. W. 2013. — A new marine vertebrate assemblage from the Late Neogene Purisima Formation in Central California, part II: Pinnipeds and Cetaceans. Geodiversitas 35 (4): 815-940. http://dx.doi.org/g2013n4a5 ABSTRACT e newly discovered Upper Miocene to Upper Pliocene San Gregorio assem- blage of the Purisima Formation in Central California has yielded a diverse collection of 34 marine vertebrate taxa, including eight sharks, two bony fish, three marine birds (described in a previous study), and 21 marine mammals. Pinnipeds include the walrus Dusignathus sp., cf. D. seftoni, the fur seal Cal- lorhinus sp., cf. C. gilmorei, and indeterminate otariid bones. Baleen whales include dwarf mysticetes (Herpetocetus bramblei Whitmore & Barnes, 2008, Herpetocetus sp.), two right whales (cf. Eubalaena sp. 1, cf. Eubalaena sp. 2), at least three balaenopterids (“Balaenoptera” cortesi “var.” portisi Sacco, 1890, cf. Balaenoptera, Balaenopteridae gen. et sp. indet.) and a new species of rorqual (Balaenoptera bertae n. sp.) that exhibits a number of derived features that place it within the genus Balaenoptera. is new species of Balaenoptera is relatively small (estimated 61 cm bizygomatic width) and exhibits a comparatively nar- row vertex, an obliquely (but precipitously) sloping frontal adjacent to vertex, anteriorly directed and short zygomatic processes, and squamosal creases.
    [Show full text]
  • Evolução, Hegemonia E Desaparecimento Dos Sirénios Dos Mares Europeus Ao Longo Do Cenozoico
    Universidade de Lisboa Faculdade de Ciências Departamento de Geologia Evolução, hegemonia e desaparecimento dos sirénios dos mares europeus ao longo do Cenozoico causas endógenas (alterações climáticas globais) ou exógenas (ambiente galáctico)? Gonçalo Abreu Prista Dissertação Mestrado em Ciências do Mar 2012 Universidade de Lisboa Faculdade de Ciências Departamento de Geologia Evolução, hegemonia e desaparecimento dos sirénios dos mares europeus ao longo do Cenozoico causas endógenas (alterações climáticas globais) ou exógenas (ambiente galáctico)? Gonçalo Abreu Prista Dissertação Mestrado em Ciências do Mar Orientadores: Professor Doutor Mário Albino Cachão Professor Doutor Rui Jorge Agostinho 2012 EVOLUÇÃO, HEGEMONIA E DESAPARECIMENTO DOS SIRÉNIOS DOS MARES EUROPEUS AO LONGO DO CENOZOICO causas endógenas (alterações climáticas globais) ou exógenas (ambiente galáctico)? GONÇALO ABREU PRISTA ORIENTAÇÃO CIENTÍFICA: PROF. DOUTOR MÁRIO ALBINO PIO CACHÃO Professor Auxiliar Agregado do Departamento de Geologia da Faculdade de Ciências da Universidade de Lisboa Membro do Centro de Geologia da Universidade de Lisboa PROF. DOUTOR RUI JORGE AGOSTINHO Professor Auxiliar Agregado do Departamento de Física da Faculdade de Ciências da Universidade de Lisboa Membro do Centro de Astronomia e Astrofísica da Universidade de Lisboa Director do Observatório Astronómico de Lisboa iii "Graças aos descobrimentos da Paleontologia, a História Natural é História, no sentido literal da palavra" Albert Gaudry (1827 - 1908). "O azoto no nosso DNA, o cálcio nos nossos dentes, o ferro no nosso sangue, o carbono nas nossas tartes de maçã foram feitos no interior de estrelas em colapso. Nós somos feitos de material estelar" Carl Sagan (1934 - 1996) iv AGRADECIMENTOS Primeiro aos meus pais, pois sem o seu apoio, a todos os níveis, este mestrado e esta dissertação não seriam possíveis.
    [Show full text]
  • Sirenian Feeding Apparatus: Functional Morphology of Feeding Involving Perioral Bristles and Associated Structures
    THE SIRENIAN FEEDING APPARATUS: FUNCTIONAL MORPHOLOGY OF FEEDING INVOLVING PERIORAL BRISTLES AND ASSOCIATED STRUCTURES By CHRISTOPHER DOUGLAS MARSHALL A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNrVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REOUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 1997 DEDICATION to us simply as I dedicate this work to the memory of J. Rooker (known "Rooker") and to sirenian conservation. Rooker was a subject involved in the study during the 1993 sampling year at Lowry Park Zoological Gardens. Rooker died during the red tide event in May of 1996; approximately 140 other manatees also died. During his rehabilitation at Lowry Park Zoo, Rooker provided much information regarding the mechanism of manatee feeding and use of the perioral bristles. The "mortality incident" involving the red tide event in southwest Florida during the summer of 1996 should serve as a reminder that the Florida manatee population and the status of all sirenians is precarious. Although some estimates suggest that the Florida manatee population may be stable, annual mortality numbers as well as habitat degradation continue to increase. Sirenian conservation and research efforts must continue. ii ACKNOWLEDGMENTS Research involving Florida manatees required that I work with several different government agencies and private parks. The staff of the Sirenia Project, U.S. Geological Service, Biological Resources Division - Florida Caribbean Science Center has been most helpful in conducting the behavioral aspect of this research and allowed this work to occur under their permit (U.S. Fish and Wildlife Permit number PRT-791721). Numerous conversations regarding manatee biology with Dr.
    [Show full text]
  • Nishiwaki, M., T. Kasuya, N. Miyazaki, T. Tobayama and T. Kataoka. Present Distribution of the Dugong
    PRESENT DISTRIBUTION OF THE DUGONG IN THE WORLD MASAHARU NISHIWAKI University of the Ryukyus, Naha, Okinawa TOSHIO KASUYA Ocean Research Institute, University ef Tokyo, Tokyo NOBUYUKI MIYAZAKI National Science Museum, Tokyo TERVO TOBAYAMA Kamogawa Sea World, Kamogawa, Chiba AND TERVO KATAOKA Toba Aquarium, Toba, Mie ABSTRACT This is a result of hearing surveys on dugong distribution in the past 10 years. The species is distributed widely in the Indo-Pacific Ocean, between the longitude of 30°E and l 70°E, and between the latitude of 30°N and 30°S. Although nothing is known on movement and seasonal migration of the species, discontinuity of distribution or of density suggests the presence of at least five populations. They are (1) east Australian and east Papua New Guinean group, (2) west Australia-Molucca-Philippine group, (3) Sumatura­ Malaysia-Andaman group, (4) Indo-Sri Lanka group and (5) east African and Madagascar group. Their range might have been continuous before depletion by human activities, and the first three populations may still be continuous dispersely. The forth and fifth group seems to be on the verge of extinction. The total population of 30,000 individuals is roughly presumed by Nishiwaki. INTRODUCTION Since the Human Environment Conference of the United Nations held at Stockholm in 1972, conservation of marine mammals has been called loudly. Particularly calls were concentrated on cetaceans. Then conservation on sirenians followed as a matter of concern. Studies on the dugong and the species of mana­ tees have progressed at the same time (Bertram, 1976). The first step needed for conservation is to clarify the habitat, range of dis- Sci.
    [Show full text]
  • Saltwater Crocodiles and Dugongs Bonus Lesson
    Great Barrier Reef - Saltwater Crocodiles and Dugongs Bonus Lesson Calendar Time https://www.youtube.com/watch?v=aN-rnqdjDI0 Music - Please continue to practice the program songs. I am Special https://www.youtube.com/watch?v=39o3yfqzf8o Jesus is Alive https://www.youtube.com/watch?v=HmWGY17kLnY&t=1s You Are My Sunshine https://www.youtube.com/watch?v=j1zNfHrKZHE Clap Your Hands and Wind the Bobbin Up https://www.youtube.com/watch?v=kMDpOKUY5yk Fun dance video KIDZ BOP Kids - Dance Monkey (Dance Along) Word Work- Trace, Cut, Match and Paste -at worksheet. Learning Without Tears- Use straights and curves you find around the house to write out your last name. Remember to start with a capital letter and follow with lower case letters. Building- Use your blocks to make a maze. Pretend that you have a dugong that is searching for seagrass. Have him follow the maze you built to make it to the grass at the end. This can be really fun to build if you have legos and a project board. Make the path just wide enough for a marble to roll through. Place the marble in your maze and tilt to board to help it roll through the maze. Science- You will need three clear cups, water, salt, food coloring (any color) and an ice cube. • Help your kids measure out one cup of water for each of the three cups. • Leave one alone and add two tablespoons of salt in the other two. Make sure to let your kids measure and pour. Stir the salt into the water to help it dissolve.
    [Show full text]
  • The Giant Sea Mammal That Went Extinct in Less Than Three Decades
    The Giant Sea Mammal That Went Extinct in Less Than Three Decades The quick disappearance of the 30-foot animal helped to usher in the modern science of human-caused extinctions. JACOB MIKANOWSKI, THE ATLANTIC 4/19/17 HTTPS://WWW.THEATLANTIC.COM/SCIENCE/ARCHIVE/2017/04/PLEIST OSEACOW/522831/ The Pleistocene, the geologic era immediately preceding our own, was an age of giants. North America was home to mastodons and saber-tooth cats; mammoths and wooly rhinos roamed Eurasia; giant lizards and bear-sized wombats strode across the Australian outback. Most of these giants died at the by the end of the last Ice Age, some 14,000 years ago. Whether this wave of extinctions was caused by climate change, overhunting by humans, or some combination of both remains a subject of intense debate among scientists. Complicating the picture, though, is the fact that a few Pleistocene giants survived the Quaternary extinction event and nearly made it intact to the present. Most of these survivor species found refuge on islands. Giant sloths were still living on Cuba 6,000 years ago, long after their relatives on the mainland had died out. The last wooly mammoths died out just 4,000 years ago. They lived in a small herd on Wrangel Island north of the Bering Strait between the Chukchi and East Siberian Seas. Two-thousand years ago, gorilla-sized lemurs were still living on Madagascar. A thousand years ago, 12-foot-tall moa birds were still foraging in the forests of New Zealand. Unlike the other long-lived megafauna, Steller’s sea cows, one of the last of the Pleistocene survivors to die out, found their refuge in a remote scrape of the ocean instead of on land.
    [Show full text]
  • 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]