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Animal Body Plans II Choanoflagellates Fungi Porifera (Sponges) Major Animal Animalia Multicellularity Ctenophora Phyla

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Animal Body Plans II Choanoflagellates Fungi Porifera (Sponges) Major Animal Animalia Multicellularity Ctenophora Phyla Animal body plans II Choanoflagellates Fungi Porifera (Sponges) Major animal Animalia multicellularity Ctenophora phyla Cnidaria diploblasty Acoels LOPHOTROCHOZOAN Rotifera Loss of coelom Platyhelminthes triploblasty Segmentation Annelida Protostome development PROTOSTOMES Mollusca BILATERA ECDYSOZOA Nematoda Cephalization, CNS, coelom Arthropoda Segmentation DEUTEROSTOMES Echinodermata Radial symmetry (adults) DEUTEROSTOMES Deuterostome development Chordata Segmentation Freeman 2014 Three tissue layers • Acoels • No coelom • Bilaterally symmetric • Simple digestive tract (no gut, no specialized Symsagittifera roscoffensis digestive cells) • Sac body plan • Cilia cover body • Asexual and hermaphroditic Porifera The protostomes ANIMALS Ctenophora Cnidaria Acoela LOPHOTROCHOZOA Rotifera Platyhelminthes Annelida PROTOSTOMES Mollusca Protostome development ECDYSOZOA Nematoda Tardigrada Coelom Onychophora Arthropoda Echinodermata Chordata LOPHOTROCHOZOA Water-to-Land Transition Rotifera Platyhelminthes Annelida Mollusca All aquatic ECDYSOZOA Some terrestrial Nematoda All terrestrial Tardigrada Onychophora Arthropoda Echinodermata Chordata Protostomes - Lophotrochozoa (a) Lophophores function (b) Trochophore larvae in suspension feeding swim and may feed. in adults. Food particles Water current Anus Mouth Mouth (in the center Cilia used in of the ring locomotion of ciliated and feeding tentacles) Anus Gut 0.1 mm 0.1 mm (a) Mouthparts for (b) Mouthparts for (c) Mouthparts for suspension deposit feeding mass feeding feeding Eversible proboscis with sharp fangs impales prey Feathery mouthparts capture Long, sticky tentacles reach plankton across substrate and deliver organic particles to mouth (worm body remains hidden) Porifera MALS Ctenophora Rotifera Cnidaria Acoela LOPHOTROCHOZOA • Bilateral symmetry Rotifera • Three germ layers Platyhelminthes • pseudocoelomate Annelida PROTOSTOMES • digestive tract with Mollusca Protostome development 2 openings ECDYSOZOA Nematoda Tardigrada Coelom Onychophora Arthropoda Echinodermata Chordata 8 Porifera MALS Ctenophora Platyhelminthes Cnidaria Acoela LOPHOTROCHOZOA • Bilateral Rotifera symmetry Platyhelminthes • Three true tissue Annelida layers (ectoderm, PROTOSTOMES Mollusca Protostome endoderm and development ECDYSOZOA mesoderm) Nematoda • acoelomate Tardigrada • sac body plan Coelom Onychophora Arthropoda Echinodermata Chordata 9 Planarian Nervous System branching gut pharynx (protruded) Digestive system Reproductive System 10 Porifera MALS Ctenophora Annelida Cnidaria Acoela LOPHOTROCHOZOA • Bilateral Rotifera symmetry Platyhelminthes • Three germ Annelida layers PROTOSTOMES Mollusca Protostome • coelomate development ECDYSOZOA Nematoda • complex digestive tract Tardigrada with 2 openings Coelom Onychophora • Segmentation Arthropoda Echinodermata Chordata 11 Annelids: Segments Galore • Segments have bristles (chaetae or setae) • Oligochaetes (few bristles) • Polychaetes (many bristles) • Leeches (none) 12 Annelids use their chaetae for burrowing • Midbody, transverse section of earthworm longitudinal muscles dorsal blood coelom cuticle circular vessel muscles Clitellum seta (retracted) nephridium ventral blood nerve cord vessel Hydrostatic skeleton 13 Porifera MALS Ctenophora Mollusca Cnidaria Acoela LOPHOTROCHOZOA • Bilateral Rotifera symmetry Platyhelminthes • Three germ Annelida layers PROTOSTOMES Mollusca Protostome • coelomate development ECDYSOZOA Nematoda • complex digestive tract Tardigrada with 2 openings Coelom Onychophora Arthropoda Echinodermata Chordata 14 Common Molluscan themes • muscular foot and a mantle • shell which encloses the visceral mass • A true coelom, reduced, limited to region around the heart • Circulatory system • Radula 15 Diverse Molluscan Body Plans • A bivalve 16 Molluscan locomotion 17 Figure 34.8 Stripes are waves of muscle contraction Diverse Molluscan Body Plans: Cephalopods • Squid – supreme predators 19 Diverse Molluscan Body Plans: Gastropods • A gastropod – a “mistake” in evolutionary experimentation? Torsion of viscera BEFORE TORSION AFTER TORSION mouth mouth anus anus, which discharges into mantle cavity 21 Diverse molluscs: gastropods 22 Protostomes - Ecdysozoa (a) Lophotrochozoans grow b) Ecdysozoans grow incrementally. by molting. Cuticles or exoskeletons Growth bands Porifera MALS Ctenophora Nematoda Cnidaria Acoela LOPHOTROCHOZOA • Bilateral symmetry Rotifera • Three germ layers Platyhelminthes • pseudocoelomate Annelida PROTOSTOMES • digestive tract with Mollusca Protostome development 2 openings ECDYSOZOA Nematoda Tardigrada Coelom Onychophora Arthropoda Echinodermata Chordata 24 Roundworms thrive in nearly all environments mouth • Cylindrical body piercing device (retracted) • Cuticle ring of nerves pharynx • Complete digestive system intestine • Male and female psuedocoelom ovary (eggs cuticle over develop here) epithelial tissue and muscle cells pore (sperm enter and eggs are released through this one) anus 25 Roundworm locomotion Porifera MALS Ctenophora Tradigrada Cnidaria Acoela • Bilateral symmetry LOPHOTROCHOZOA Rotifera • Three germ layers Platyhelminthes • coelomate Annelida • complex digestive PROTOSTOMES Mollusca tract with 2 Protostome development openings ECDYSOZOA Nematoda • segmentation Tardigrada Coelom Onychophora Arthropoda Echinodermata Chordata 27 Tardigrada Porifera MALS Ctenophora Onychophora Cnidaria Acoela • Bilateral symmetry LOPHOTROCHOZOA • Three germ layers Rotifera • coelomate Platyhelminthes • complex digestive Annelida tract with 2 PROTOSTOMES openings Mollusca Protostome development • Segmented ECDYSOZOA Nematoda • Stub feet • Velvet worms Tardigrada Coelom Onychophora Arthropoda Echinodermata Chordata 29 Porifera MALS Ctenophora Arthropoda Cnidaria Acoela • Bilateral symmetry LOPHOTROCHOZOA Rotifera • Three germ layers Platyhelminthes • coelomate Annelida • complex digestive PROTOSTOMES Mollusca tract with 2 Protostome development openings ECDYSOZOA Nematoda • Segmentation Tardigrada • exoskeletons Coelom Onychophora Arthropoda Echinodermata Chordata 30 Arthropods – most successful organisms (Other than prokaryotes) • Over one million species Major lineages: Chelicerates Trilobites Crustaceans (extinct) Uniramians 31 Adaptations of Arthropods • Hardened exoskeleton • Jointed appendages • Fused and modified segments • Head, Thorax, Abdomen 32 Adaptations of Arthropods • Specialized respiratory structures • Gills or tracheas • Efficient nervous system and sensory organs • Eyes - vision • Divisions of labor in the life cycle • Metamorphosis • Growth • Molting 33 A Look at Crustaceans • Vast majority are marine • Lobsters, crabs, shrimps • Copepods • Less than 2mm long • Barnacles • Calcified shell 34 Crustaceans 35 Barnacle biology Uniramians • Include insects, millipedes, and centipedes. • Head and thorax limbs one branch • Paired head appendages • Tracheae • Metamorphosis 37 Chelicerates • Include terrestrial spiders, scorpions, ticks, mites, horseshoe crabs and sea spiders. • First pair of appendages (chelicerae) are feeding organs. • Second pair of appendages (pedipalps) function in feeding or sensory. • All appendages attached to cephalothorax. • No appendages on heads. 38 Porifera ANIMALS Ctenophora Deuterostomes Cnidaria Acoela PROTOSTOMES Rotifera Platyhelminthes Annelida Mollusca Nematoda Tardigrada Onychophora Arthropoda DEUTEROSTOMES Echinodermata Hemichordata Xenoturbellida Deuterostome development Chordata (includes vertebrates) Porifera ANIMALS Ctenophora Echinodermata Cnidaria Acoela PROTOSTOMES • Symmetry?! Rotifera Platyhelminthes • Three germ layers Annelida Mollusca • Coelomate Nematoda • digestive tract with Tardigrada Onychophora 2 openings Arthropoda DEUTEROSTOMES Echinodermata Hemichordata Xenoturbellida Deuterostome development Chordata (includes vertebrates) 40 The Puzzling Echinoderms • Why puzzling? • bilateral larvae (usually) • radially symmetrical Anus adults Spines Tube feet Stomach TUBE FEET CANALS 41 Echinoderm diversity 42 Porifera ANIMALS Ctenophora Chordates Cnidaria Acoela PROTOSTOMES • Symmetry?! Rotifera Platyhelminthes • Three germ layers Annelida Mollusca • Coelomate Nematoda • digestive tract with Tardigrada Onychophora 2 openings Arthropoda DEUTEROSTOMES Echinodermata Hemichordata Xenoturbellida Deuterostome development Chordata (includes vertebrates) 43 Features of Chordates • A notochord • A tubular dorsal nerve chord • Embryos have distinctive silts in wall of pharynx, a muscularized tube • A tail forms in embryos and extends past anus mammals birds reptiles amphibians bony fishes cartilaginous Invertebrate Chordates ancestral chordate ancestral fishes jawless fishes tunicates lancelets no vertebrae 45 Subphylum: tunicates a. Larval form nerve cord notochord intestine b. Larval metamorphosis oral opening atrial opening (exit of water) pharynx with gill slits 46 Subphylum: lancelets DORSAL, TUBULAR TAIL EXTENDING NERVE CORD PHARYNX WITH PAST ANUS NOTOCHORD GILL SLITS aorta anus epidermis gonad hindgut pore of segmented midgut tentacles atrial cavity around muscles mouth • Unlike Tunicates, have a closed circulatory system, • but not red blood cells •Filter47 feeders mammals birds reptiles amphibians vertebrae bony fishes Subphylum: Vertebrae cartilaginous fishes jawless fishes tunicates lancelets 48 Vertebrate developments • Living Endoskeleton • includes a skull • backbone is composed of vertebrae Backbone • Paired limbs • High degree of cephalization • Efficient respiration & excretion • Closed circulatory system 49 Vertebrate developments supporting structures • Most vertebrates have Jaws Early jawless fish (an Agnathan) gill slit Early jawed fish (a Placoderm) jaw spiracle (small gill slit) jaw support Modern jawed fish (a shark) jaw 50 .
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