Kingdom ANIMALIA Subkingdom Eumetazoa Lophotrochozoa True

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Kingdom ANIMALIA Subkingdom Eumetazoa Lophotrochozoa True

Kingdom ANIMALIA Subkingdom Eumetazoa Lophotrochozoa Basal animals True tissues Phylum Porifera Cnidaria Platyhelminthes Rotifera Ectoptocta Brachiopoda Mollusca Annelida Symmetry no symmetry Radial Bilateral Bilateral Bilateral Bilateral Bilateral Bilateral Body Cavity none none Acoelomate psuedocoelomate Coelomate Coelomate Reduced Organization No tissues True tissues Organ-system Organ-system Organ-system Organ-system Organ-system Organ-system Development Protostome Protostome Deutrostome Deutrostome Protostome Protostome Segmentation unsegmented Lophophore unsegmented segmented Tiny animals Colonial animals hinged shell Characters 2 layers 2 layers Flat worms Crown of cilia Hard exoskeleton like clams soft-bodied segmented Choanocytes Cnidocytes solid, 3-layered, surround mouth with pores most stalked complete DigSys completeDigSys Spicules Polyp, Medusa mouth/anus Both marine & Lophophores 2 partsof shell may have shell most have Filter-feeder only mouth leads to fresh water emerge from pores are dorsal and head, foot and chetae many pores gastrovascular Digestive system Look like mosses ventral viseral mass hydroskeleton cavity, mouth stomach Bryozoa means rasping radula free living or anus moss animals only marine Examples Grantia Hydra parasitic Separate body Some reef builder Physalia central nervous cavity Jelly fish system Some have only Sea mat Snail Neries Sea Anemone Planaria females Membranipora Oyster Earthworm Corals Flukes Parthenogenesis membranacea Lamp shell Squid Leech Tape worm Bdelloid Octopus Ecdysozoa Deutrostomia Nematoda Arthropoda Echinodermata Chordata Bilateral Bilateral Bilateral larva Bilateral Adult radial Pseudocoelomate Coelomate Coelomate Coelomate Organ-system Organ-system Organ-system Organ-system Protostome Protostome Deutrostome Deutrostome unsegmented segmented segmented Round worms Exoskeleton Spiny-skinned Notochord complete DigSys completeDigSys Endoskeleton of dorsal nerve cord no cilia paired, jointed bony plates pharyngeal pouches live in soil or appendages water vascular have tail animal parasite most insects system, tubefeet most with backbone covered with have wings high regeneration gills or lungs cuticle Only marine Heart and vessels Molting Insect-butterfly Sea star Lamprey Crustacea-crab Sea urchin sharks Ascaris millipede sea cucumber salmon, tuna centipede brittle star frog, salamander spiders feather star lizard, turtle, scorpion pigeon, sea-gull kangaroo, bat, rat.

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Defining Phyla: Evolutionary Pathways to Metazoan Body Plans
EVOLUTION & DEVELOPMENT 3:6, 432-442 (2001) Defining phyla: evolutionary pathways to metazoan body plans Allen G. Collins^ and James W. Valentine* Museum of Paleontology and Department of Integrative Biology, University of California, Berkeley, CA 94720, USA 'Author for correspondence (email: [email protected]) 'Present address: Section of Ecology, Befiavior, and Evolution, Division of Biology, University of California, San Diego, La Jolla, CA 92093-0116, USA SUMMARY Phyla are defined by two sets of criteria, one pothesis of Nielsen; the clonal hypothesis of Dewel; the set- morphological and the other historical. Molecular evidence aside cell hypothesis of Davidson et al.; and a benthic hy- permits the grouping of animals into clades and suggests that pothesis suggested by the fossil record. It is concluded that a some groups widely recognized as phyla are paraphyletic, benthic radiation of animals could have supplied the ances- while some may be polyphyletic; the phyletic status of crown tral lineages of all but a few phyla, is consistent with molecu- phyla is tabulated. Four recent evolutionary scenarios for the lar evidence, accords well with fossil evidence, and accounts origins of metazoan phyla and of supraphyletic clades are as- for some of the difficulties in phylogenetic analyses of phyla sessed in the light of a molecular phylogeny: the trochaea hy- based on morphological criteria. INTRODUCTION Molecules have provided an important operational ad- vance to addressing questions about the origins of animal Concepts of animal phyla have changed importantly from phyla. Molecular developmental and comparative genomic their origins in the six Linnaean classis and four Cuvieran evidence offer insights into the genetic bases of body plan embranchements.
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