DOCSLIB.ORG

Catching The

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Catching The NEWS AND VIEWS DAEDALUS------- ,-----------Coelenterates (2) modified arthropods. Such an idea fits ----{=====Chordates (4) well enough with the evidence that mol­ r Echinoderms (4) Catching the eye -------- Insect luscs are primitively metameric, but it 1---------Millipede does not fit traditional ideas on the de­ DAEDALUS once invented a novel women's ,--------Chelicerate velopment of the coelomic body cavity. anti-wrinkle face cream, inspired by those ,.....-----Crustaceans (3) ,-----Oligochaete annelid Annelid worms have a capacious spectacle lenses that darken in sunlight. Its 1-----Polychaate annelid coelom, as do vertebrates, but arthropods fast-acting pigment lightened in the L.....r----- Pogonophore and molluscs have only rudimentary shadowed crevices of the wearer's face, but Braohiopod CMon coelomic cavities, generally interpreted as darkened on the smooth well-lit areas -""1---Nudibranch ~use reduced or vestigial. The major body between them. This abolition of optical Bivalve molluscs (2) cavity in arthropods is the haemocoel, a contrast made the wearer's wrinkles almost Sipunculid capacious blood circulatory system which impossible to detect. Unfortunately, it also FIG . 2 Topology interpreted from two trees8 in some arthropods and molluscs serves abolished perception of her facial style and calculated by evolutionary parsimony from the much the same function - a hydrostatic expression. The new cosmetic turned the same alignment of 18S rRNA as Fig. 1, with skeleton - as does the coelom in an­ most vivacious woman into a sort of dead­ the addition of three crustacean sequences (a nelids. The most widely accepted schemes pan zombie. Bafflingly, it sold mainly to conchostracan, a notostracan and a pen­ of coelomate history treat arthropods and men - government spokesmen, tastomid19) . Numbers in brackets after group psychia­ names indicate the number of species molluscs as derived from annelid-like an­ trists, police interrogators, and others sampled . The tree is rooted on the coelenter­ cestors by reduction of the coelom of the anxious to give nothing away. 8 20 ates. In the published tree the three longest circulatory system into a haemocoel'· • But So Daedalus is now turning the idea on its (most rapidly evolving) branches are Droso­ Lake's tree implies that a haemocoel is head. Some pigments, like thionine, amplify phila, the sipunculid Golfingia and the tuni­ primitive for protostomes (Fig. 2, insect optical contrast: they are bleached by light, cate Styela, respectively with about 56, 55 and below) because haemocoelic animals and darkened by shade. DREADCO's new and 37 transversions per 1,000 nucleotides. branch off at each of the first three nodes. 'Eyecatcher' cosmetics use this effect to Echinoderms (a crinoid , an echinoid, a brit­ In dealing with relationships as remote enhance the optical contrast of a woman's tlestar and a starfish) did not emerge as as those between arthropods and other face, giving her an appealing facial live­ monophyletic in the published tree. phyla, we are certainly asking about liness and dynamism. Contrast amplifica­ more, but it has not yet been put to work). events in the Precambrian, because tion is fast, but limited to the red region of In many-taxon problems, Lake gets round arthropods, molluscs and brachiopods are the spectrum, so that blushing and other this disadvantage by repeated sampling, all known in early Cambrian rocks. Inter­ dynamics of complexion are emphasized, 20 calculating four-taxon trees, retaining all estingly, Valentine , in a recent analysis while the wrinkles are largely left alone. those with a central branch supported at of late Precambrian metazoan trace and Daedalus is even formulating an Eye­ the level of 5 per cent significance, and body fossils, concluded that the haemocoel catcher face cream for men, with a promise combining taxon pairs that are supported preceded the coelom, that arthropods did of added cragginess, stubblier stubble, and in every four-taxon tree containing them. not replace a capacious coelom but never heightened moodiness of expression. And Lake's metazoan tree (Fig. 2) shows the had one, and that arthropods did not arise for actors, Eyecatcher grease-paint wiJJ Deuterostomia (Echinodermata + Chor­ "from some plexus of annelid precursors, convey the most subtle nuances of dramatic data) as monophyletic, as does parsimony but that annelids arose from among a anguish to the cheapest and most distant 6 analysis of the same data'· • Because plexus of arthropod ancestors". Such seats. evolutionary parsimony deals only with ideas seem best tested by analysis of fur­ Eyecatcher colours should also prove unrooted trees ( as do all methods of ther sequences from molecules conserved popular in clothing. Their exaggeration of analysing sequence data, unless one roots since the Precambrian, and 28S (large contrast between highlight and shadow on a particular taxon), Lake used coelen­ subunit) rRNA is an obvious target. D would subtly emphasize the contours and terates as the outgroup and looked for dynamics of the wearer's figure. This cun­ roots significant at the 5 per cent level. All Colin Patterson is in the Department of Pal­ ning anti-camouflage would call attention aeontology, The Natural History Museum, five of those roots render arthropods London SW7 580, UK. to the body far more beguilingly than con­ paraphyletic, but one (Fig. 2) matches the ventional fluorescent colours. Joggers, traditional dichotomy between deutero­ 1. Field , K.G. et al. Science 239. 748-753 (1988). exhibitionists, entertainers and their many stomes and protostomes. Within pro­ 2. Walker, W.F. Science 243, 548-549 (1989). imitators would welcome Eyecatcher cloth­ tostomes, this makes the two uniramians 3. Bode , H.R & Steele, R.E. Science 243, 549 (1989). 4. Ax , P. in TheHierarchyofLife (edsFemholm, B., Bremer, ing, and so would hikers or explorers (insects + myriapods) in this sample, in­ K. & Jornvall, H.) 229-245 (Excerpta Modica , Amster­ setting out into dangerous wildernesses. dividually or together, the sister-group of dam, 1989). Mothers, teachers and prison governors 5 . Ghiselin, M.T. Oxford Survs £vol. Biol. 5, 66-95 (1988). the remaining arthropods (Chelicerata, 6 . Patterson, C. in The Hierarchy of life (eds Femholm, B., would also be keen to issue it to their more Crustacea) plus the annelids, pogono­ Bremer, K. & Jornvall , H.) 471-488 (Excerpta Medica, furtive and evasive charges. Amsterdam, 1989). phore, brachiopod, molluscs and sipun­ 7. Lake, J.A. in The Hierarchy of Life (eds Femholm, B .. In the form of paints and decorative culid. Further, the most probable position Bremer, K. & Jornvall, H.) 273-278 (Excerpta Medica, material, Eyecatcher dyes would give of the sipunculid is as the sister of bivalve Amsterdam, 1989). 8 . Lake, J.A. Proc. natn. Acad. Sci. U.S.A. 87, 763-766 a splash of added drama and impact to molluscs, so rendering the Mollusca para­ (1990). everything they touched. The depth of con­ phyletic (molluscs did not emerge as 9 . Manton, S.M. The Arthropoda (Clarendon, Oxford, trast that gives the sunlit tropics their sharp 1977). monophyletic in any of the distance or 10. Boudreaux, H.B. Arthropod Phylogeny with Special and almost passionate surreality, could be 6 parsimony trees,. ). Reference to Insects (Wiley, New York, 1979). magicaJJy imported into a misty northern 11. Lake, J.A. Mo/. Biol. £vol. 4, 167-191 (1987). In the more distal part of the 18S rRNA 12. Jin , L. & Nei, M. Mo/. Biol. £vol. 7 , 82-102 (1990). townscape or a quiet domestic interior. 19 tree, Abele and others have used Lake's 13. Li , W.H, Wolfe, K.H., Sourdis, J. & Sharp, P.M . Cold Eyecatcher varnish would bring out the method to confirm (P < 0.04) that the Spring HartJ. Symp. quant. Biol. 52, 84 7--856 (1987). 14. Penny, D. Nature 331, 111- 112 (1988). surface detail of engineering components Pentastomida (tongue worms), parasites 15. Lake, J.A. Nature 343, 418-419 (1990). under inspection. And antique dealers of tetrapod vertebrates usually given a 16. Gouy, M. & Li, W.H. Nature 343,419 (1990). would craftily apply it to their more bat­ 17. Felsenstein, J. Nature 335, 188 (1988). phylum of their own, are modified crust­ 18. Cavender, J.A. Mo/. Biol. £vol. 6, 301-316 (1989). tered offerings, to point up cracks, warp­ aceans. Lake's tree might be read as 19. Abele, L.G., Kim, W. & Felgenhauer, B.E. Mo/. Biol. £vol. ing, grain, worm-holes and the other 6, 685----691 (1989). indicating that in cladistic terms annelids, 20. Valentine, J.W. Proc. natn. Acad. Sci. U.S.A. 88, 2272- authenticating stigmata of great age. molluscs and the other minor phyla are 2275 (1989). David Jones 200 NATURE · VOL 344 · 15 MARCH 1990 .
Load more

Recommended publications
  • 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.
    [Show full text]
  • A Parasitological Evaluation of Edible Insects and Their Role in the Transmission of Parasitic Diseases to Humans and Animals
    RESEARCH ARTICLE A parasitological evaluation of edible insects and their role in the transmission of parasitic diseases to humans and animals 1 2 Remigiusz GaøęckiID *, Rajmund Soko ø 1 Department of Veterinary Prevention and Feed Hygiene, Faculty of Veterinary Medicine, University of Warmia and Mazury, Olsztyn, Poland, 2 Department of Parasitology and Invasive Diseases, Faculty of Veterinary Medicine, University of Warmia and Mazury, Olsztyn, Poland a1111111111 a1111111111 * [email protected] a1111111111 a1111111111 a1111111111 Abstract From 1 January 2018 came into force Regulation (EU) 2015/2238 of the European Parlia- ment and of the Council of 25 November 2015, introducing the concept of ªnovel foodsº, including insects and their parts. One of the most commonly used species of insects are: OPEN ACCESS mealworms (Tenebrio molitor), house crickets (Acheta domesticus), cockroaches (Blatto- Citation: Gaøęcki R, SokoÂø R (2019) A dea) and migratory locusts (Locusta migrans). In this context, the unfathomable issue is the parasitological evaluation of edible insects and their role in the transmission of parasitic diseases to role of edible insects in transmitting parasitic diseases that can cause significant losses in humans and animals. PLoS ONE 14(7): e0219303. their breeding and may pose a threat to humans and animals. The aim of this study was to https://doi.org/10.1371/journal.pone.0219303 identify and evaluate the developmental forms of parasites colonizing edible insects in Editor: Pedro L. Oliveira, Universidade Federal do household farms and pet stores in Central Europe and to determine the potential risk of par- Rio de Janeiro, BRAZIL asitic infections for humans and animals.
    [Show full text]
  • Worms, Germs, and Other Symbionts from the Northern Gulf of Mexico CRCDU7M COPY Sea Grant Depositor
    h ' '' f MASGC-B-78-001 c. 3 A MARINE MALADIES? Worms, Germs, and Other Symbionts From the Northern Gulf of Mexico CRCDU7M COPY Sea Grant Depositor NATIONAL SEA GRANT DEPOSITORY \ PELL LIBRARY BUILDING URI NA8RAGANSETT BAY CAMPUS % NARRAGANSETT. Rl 02882 Robin M. Overstreet r ii MISSISSIPPI—ALABAMA SEA GRANT CONSORTIUM MASGP—78—021 MARINE MALADIES? Worms, Germs, and Other Symbionts From the Northern Gulf of Mexico by Robin M. Overstreet Gulf Coast Research Laboratory Ocean Springs, Mississippi 39564 This study was conducted in cooperation with the U.S. Department of Commerce, NOAA, Office of Sea Grant, under Grant No. 04-7-158-44017 and National Marine Fisheries Service, under PL 88-309, Project No. 2-262-R. TheMississippi-AlabamaSea Grant Consortium furnish ed all of the publication costs. The U.S. Government is authorized to produceand distribute reprints for governmental purposes notwithstanding any copyright notation that may appear hereon. Copyright© 1978by Mississippi-Alabama Sea Gram Consortium and R.M. Overstrect All rights reserved. No pari of this book may be reproduced in any manner without permission from the author. Primed by Blossman Printing, Inc.. Ocean Springs, Mississippi CONTENTS PREFACE 1 INTRODUCTION TO SYMBIOSIS 2 INVERTEBRATES AS HOSTS 5 THE AMERICAN OYSTER 5 Public Health Aspects 6 Dcrmo 7 Other Symbionts and Diseases 8 Shell-Burrowing Symbionts II Fouling Organisms and Predators 13 THE BLUE CRAB 15 Protozoans and Microbes 15 Mclazoans and their I lypeiparasites 18 Misiellaneous Microbes and Protozoans 25 PENAEID
    [Show full text]
  • Pentastomiasis in Australian Re
    Fact sheet Pentastomiasis (also known as Porocephalosis) is a disease caused by infection with pentastomids. Pentastomids are endoparasites of vertebrates, maturing primarily in the respiratory system of carnivorous reptiles (90% of all pentastomid species), but also in toads, birds and mammals. Pentastomids have zoonotic potential although no human cases have been reported in Australia. These parasites have an indirect life cycle involving one or more intermediate host. They may be distinguished from other parasite taxa by the presence of four hooks surrounding their mouth, which they use for attaching to respiratory tissue to feed on host blood. Pentastomid infections are often asymptomatic, but adult and larval pentastomids can cause severe pathology resulting in the death of their intermediate and definitive hosts, usually via obstruction of airways or secondary bacterial and/or fungal infections. Pentastomiasis in reptiles is caused by endoparasitic metazoans of the subclass Pentastomida. Four genera are known to infect crocodiles in Australia: Alofia, Leiperia, Sebekia, and Selfia; all in the family Sebekidae. Three genera infect lizards in Australia: Raillietiella (Family: Raillietiellidae), Waddycephalus (Family: Sambonidae) and Elenia (Family: Sambonidae). Four genera infect snakes in Australia: Waddycephalus, Parasambonia (Family: Sambonidae), Raillietiella and Armillifer (Family: Armilliferidae). Definitive hosts Many species of Australian reptiles, including snakes, lizards and crocodiles are proven definitive hosts for pentastomes (see Appendix 1). Lizards may be both intermediate and definitive hosts for pentastomids. Raillietiella spp. occurs primarily in small to medium-sized lizards and Elenia australis infects large varanids. Nymphs of Waddycephalus in several lizard species likely reflect incidental infection; it is possible that lizards are an intermediate host for Waddycephalus.
    [Show full text]
  • Directorate for Biological Sciences Emerging Frontiers Theoretical
    Directorate for Biological Sciences Emerging Frontiers Theoretical Biology Proposal Classification Worksheet In each category, please choose the most specific descriptors. CATEGORY I: INVESTIGATOR STATUS (Select ONE) Beginning Investigator - No previous Federal support as PI or Co-PI, excluding fellowships, dissertations, planning grants, etc. Prior Federal support only Current Federal support only Current & prior Federal support CATEGORY II: FIELDS OF SCIENCE OTHER THAN BIOLOGY INVOLVED IN THIS RESEARCH (Select 1 to 3) Astronomy Engineering Psychology Chemistry Mathematics Social Sciences Computer Science Physics None of the Above Earth Science CATEGORY III: SUBSTANTIVE AREA (No selection required) CATEGORY IV: INFRASTRUCTURE (No selection required) CATEGORY V: HABITAT (No selection required) CATEGORY VI: GEOGRAPHIC AREA OF THE RESEARCH (No selection required) CATEGORY VII: CLASSIFICATION OF ORGANISMS (Select 1 to 4) VIRUSES Chytridiomycota Anthocerotae (Hornworts) Bacterial Mitosporic Fungi Hepaticae (Liverworts) Plant Oomycota Musci (Mosses) Animal Yeasts VASCULAR PLANTS PROKARYOTES Zygomycota FERNS & FERN ALLIES GYMNOSPERMS Archaebacteria LICHENS Cyanobacteria SLIME MOLDS Coniferales (Conifers) Cycadales (Cycads) Eubacteria ALGAE Ginkgoales (Ginkgo) PROTISTA (PROTOZOA) Bacillariophyta (Diatoms) Gnetales (Gnetophytes) Amoebae Charophyta ANGIOSPERMS Apicomplexa Chlorophyta Monocots Ciliophora Chrysophyta Arecaceae (Palmae) Flagellates Dinoflagellata Cyperaceae Foraminifera Euglenoids Liliaceae Microspora Phaeophyta Orchidaceae Radiolaria
    [Show full text]
  • The Early History of the Metazoa—A Paleontologist's Viewpoint
    ISSN 20790864, Biology Bulletin Reviews, 2015, Vol. 5, No. 5, pp. 415–461. © Pleiades Publishing, Ltd., 2015. Original Russian Text © A.Yu. Zhuravlev, 2014, published in Zhurnal Obshchei Biologii, 2014, Vol. 75, No. 6, pp. 411–465. The Early History of the Metazoa—a Paleontologist’s Viewpoint A. Yu. Zhuravlev Geological Institute, Russian Academy of Sciences, per. Pyzhevsky 7, Moscow, 7119017 Russia email: [email protected] Received January 21, 2014 Abstract—Successful molecular biology, which led to the revision of fundamental views on the relationships and evolutionary pathways of major groups (“phyla”) of multicellular animals, has been much more appre ciated by paleontologists than by zoologists. This is not surprising, because it is the fossil record that provides evidence for the hypotheses of molecular biology. The fossil record suggests that the different “phyla” now united in the Ecdysozoa, which comprises arthropods, onychophorans, tardigrades, priapulids, and nemato morphs, include a number of transitional forms that became extinct in the early Palaeozoic. The morphology of these organisms agrees entirely with that of the hypothetical ancestral forms reconstructed based on onto genetic studies. No intermediates, even tentative ones, between arthropods and annelids are found in the fos sil record. The study of the earliest Deuterostomia, the only branch of the Bilateria agreed on by all biological disciplines, gives insight into their early evolutionary history, suggesting the existence of motile bilaterally symmetrical forms at the dawn of chordates, hemichordates, and echinoderms. Interpretation of the early history of the Lophotrochozoa is even more difficult because, in contrast to other bilaterians, their oldest fos sils are preserved only as mineralized skeletons.
    [Show full text]
  • Systema Naturae. the Classification of Living Organisms
    Systema Naturae. The classification of living organisms. c Alexey B. Shipunov v. 5.601 (June 26, 2007) Preface Most of researches agree that kingdom-level classification of living things needs the special rules and principles. Two approaches are possible: (a) tree- based, Hennigian approach will look for main dichotomies inside so-called “Tree of Life”; and (b) space-based, Linnaean approach will look for the key differences inside “Natural System” multidimensional “cloud”. Despite of clear advantages of tree-like approach (easy to develop rules and algorithms; trees are self-explaining), in many cases the space-based approach is still prefer- able, because it let us to summarize any kinds of taxonomically related da- ta and to compare different classifications quite easily. This approach also lead us to four-kingdom classification, but with different groups: Monera, Protista, Vegetabilia and Animalia, which represent different steps of in- creased complexity of living things, from simple prokaryotic cell to compound Nature Precedings : doi:10.1038/npre.2007.241.2 Posted 16 Aug 2007 eukaryotic cell and further to tissue/organ cell systems. The classification Only recent taxa. Viruses are not included. Abbreviations: incertae sedis (i.s.); pro parte (p.p.); sensu lato (s.l.); sedis mutabilis (sed.m.); sedis possi- bilis (sed.poss.); sensu stricto (s.str.); status mutabilis (stat.m.); quotes for “environmental” groups; asterisk for paraphyletic* taxa. 1 Regnum Monera Superphylum Archebacteria Phylum 1. Archebacteria Classis 1(1). Euryarcheota 1 2(2). Nanoarchaeota 3(3). Crenarchaeota 2 Superphylum Bacteria 3 Phylum 2. Firmicutes 4 Classis 1(4). Thermotogae sed.m. 2(5).
    [Show full text]
  • H 1332 Biological Names
    Biological Names H 1332 BACKGROUND: Formerly, headings for names of animals and plants at particular taxonomic levels were established only when a work about an organism at that specific level was cataloged. In the early 1970s, the practice was adopted of always making the BT reference from a heading at the next higher level along the hierarchy of species-genus-family-order-class- phylum even if it meant establishing a heading for which no work had been cataloged. Intermediate levels such as superfamilies or suborders are no longer established, or retained from the old system, unless the intermediate grouping is considered particularly helpful or warranted by common usage, for example, butterflies or trout. Intermediate group names are used as additional BT references but do not replace the standard genus-family-order-class-phylum reference structure. This instruction sheet provides guidelines for establishing names of animals and plants, including domestic animal breeds, cultivated plant varieties, and fossils. 1. Level of name. Establish names of animals and plants at the following taxonomic levels only: species, genus, family, order, class, phylum, or division. Do not establish other levels, such as suborders or superfamilies except in the case of popular names for intermediate groups, such as butterflies or trout, or common names for well-known subspecies. 2. Form of name. a. Latin or common name. Prefer the common name if it is in popular use and unambiguous, using as reference sources Web. 3, other general dictionaries or encyclopedias, recent textbooks, popular field guides, and lists of official common names issued by societies or government agencies.
    [Show full text]
  • Chapter 12 Porifera
    Chapter 12 Porifera Figure 12.04 1 Unicellular Protists choanoflagellates-colonial organization Theories of Unicellular Origin of Metazoans 1) 1874-Haeckel first proposed metazoans arose from a colonial flagellated form & cells gradually became specialized 2) as cells in a colony became more specialized, the colony became dependent on them 3) colonial ancestral form was at first radially symmetrical, & reminiscent of a blastula stage of development 4) this hypothetical ancestor was called a blastea 5) another hypothetical ancestral forms similar to a gastrula may have existed, & refer to them as gastraea 6) Bilateral symmetry evolved when the planula larvae adapted to crawling on the floor 7) Molecular Evidence a) small subunit rRNA & biochemical pathways support the colonial flagellate hypothesis b) metazoans appear to be monophyletic & arising from choanoflagellates Monophyletic group contains the most recent common ancestor of all members of the group & all of its descendants 2 Unicellular (acellular) Multicellular (metazoa) protozoan protists Poorly defined Diploblastic tissue layers Triploblastic Cnidaria Porifera Ctenophora Placozoa Uncertain Acoelomate Coelomate Pseudocoelomate Priapulida Rotifera Chaetognatha Platyhelminthes Nematoda Gastrotricha Rhynchocoela (Nemertea) Kinorhyncha Entoprocta Mesozoa Acanthocephala Loricifera Gnathostomulida Nematomorpha Protostomes Uncertain (misfits) Deuterostomes Annelida Mollusca Echinodermata Brachiopoda Hemichordata Arthropoda Phoronida Onychophora Bryozoa Chordata Pentastomida Pogonophora
    [Show full text]
  • Chapter 16: Mollusca Latin: Soft 90,000 Living Spp
    Chapter 16: Mollusca Latin: soft 90,000 living spp. 70,000 fossil spp. marine fresh water terrestrial chitons tusk shells snails slugs nudibranchs sea butterflies clams mussels oysters squids/cuttlefish nautiluses octopuses Figure 16.01 1 Most Diverse Phylum 80% are under 10 cm in size some 90 kg; 20 m length herbivorous grazers predaceous carnivores filter feeders parasites Classes I. Polyplacophora: chitons, gumshoe chiton II. Gastropoda: snails, limpets, slugs, whelks, conchs, periwinkles, sea hares, sea butterflies III. Bivalvia: clams, oysters, scallops & mussels IV. Cephalopoda: nautilus, squid, cuttlefish & octopus Caudofoveata Solenogasters Monoplacophora Scaphopoda 2 Molluscs Economically Important 1) food 2) snails/slugs garden pests 3) burrowing shipworms destroy wooden ships & wharves 4) industry: pearls & pearl buttons culture 5) some snails intermediate hosts for parasites Review of General Characteristics bilateralsymmetry triploblastic coelom protostome 3 Unicellular (acellular) Multicellular (metazoa) protozoan protists Poorly defined Diploblastic tissue layers Triploblastic Cnidaria Porifera Ctenophora Placozoa Uncertain Acoelomate Coelomate Pseudocoelomate Priapulida Rotifera Chaetognatha Platyhelminthes Nematoda Gastrotricha Rhynchocoela Kinorhyncha Entoprocta Mesozoa Acanthocephala Loricifera Gnathostomulida Nematomorpha Protostomes Uncertain (misfits) Deuterostomes Annelida Mollusca Echinodermata Brachiopoda Hemichordata Arthropoda Phoronida Onychophora Bryozoa Chordata Pentastomida Pogonophora Sipuncula Echiura
    [Show full text]
  • BMC Genomics Biomed Central
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by PubMed Central BMC Genomics BioMed Central Research article Open Access The complete mitochondrial genome of the sea spider Nymphon gracile (Arthropoda: Pycnogonida) Lars Podsiadlowski*1 and Anke Braband2 Address: 1Department of Animal Systematics and Evolution, Institute of Biology, Freie Universität Berlin, Konigin-Luise-Str. 1-3, D-14195 Berlin, Germany and 2Department of Comparative Zoology, Institute of Biology, Humboldt Unversität, Phillipstr. 13, D-10115 Berlin, Germany Email: Lars Podsiadlowski* - [email protected]; Anke Braband - [email protected] * Corresponding author Published: 06 November 2006 Received: 13 June 2006 Accepted: 06 November 2006 BMC Genomics 2006, 7:284 doi:10.1186/1471-2164-7-284 This article is available from: http://www.biomedcentral.com/1471-2164/7/284 © 2006 Podsiadlowski and Braband; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract Background: Mitochondrial genomes form units of genetic information replicating indepentently from nuclear genomes. Sequence data (most often from protein-coding genes) and other features (gene order, RNA secondary structure) of mitochondrial genomes are often used in phylogenetic studies of metazoan animals from population to phylum level. Pycnogonids are primarily marine arthropods, often considered closely related to chelicerates (spiders, scorpions and allies). However, due to their aberrant morphology and to controversial results from molecular studies, their phylogenetic position is still under debate.
    [Show full text]
  • Beneficial Insects
    I. M.W. Service. ( 2008). Medical Entomology for students. 4nd edition. II. Biology of disease Vectors II. Different search engines, especially WHO (TDR) Medical Entomology What will I be talking about? . Arthropods . Phtiraptera ( Lice) . Siphonaptera (fleas) . Hemiptera ( Bed bugs and kissing bugs) Howwwwww? Medical entomology The role of insects in the causation of human disease • Bites and stings • Allergic reaction (cockroach, house dust mite) • True parasite ( Scabies) • Vectors ( Malaria, Leishmaniasis, yellow fever, Chagas) •African trypanosomiasis •Dengue fever •Leishmaniasis •Malaria •Chagas disease •Onchocerciasis •Lymphatic filariasis Arthropod The largest phylum of animals The most successful animals Introduction to the Arthropods The real ruler of the earth Arthropods range in distribution from the deep sea to mountain peaks In size from the king crab with its 12-foot to microscopic insects and crusteaca 1 feet = 30cm In spite of being a diverse group They share some basic inherited characters Classification . Kingdom: Animalia Phylum: Arthropoda Class: I-Arachnida II- Chilopoda III- Diplopoda IV- Crustacea V- Pentastomida VI- Insecta Arachnida: Scorpionida Aranea Acarina Diplopoda ( millipedes) Two pairs of legs per segment, except,. The giant African millipede 25 cm Chilopoda (Centipedes) • One pair of legs per body segment • A pair of venom claws or forcipes Size can range from a few millimeters 30 cm Crustacea • Pentastomida live in the respiratory tracts of snakes and reptiles. • Humans acquire the disease when they ingest uncooked snake, contaminated water, or contaminated food. Pentastomiasis is mostly asymptomatic, it is not a primary health threat. Insecta ( 56%) Phyllum : Arthropoda Class: Insecta ( 32 orders) 1. Hemiptera 2. Pthiraptera 3. Diptera 4. Siphonaptera 5.
    [Show full text]