Most animals (>95%) are inverts Aside from very successful insects, most animals are marine

1. Kingdom Animalia – all animals are multicellular heterotrophs that lack cell walls and share the first few steps of early embryology

2. Most animals (>95%) are inverts Aside from very successful insects, most animals are marine Diverse morphologies, habitats, and adaptations Animals are very diverse in form, organization, and complexity from the simplest invertebrates to more complex vertebrates

3. Prokaryotes • Domain Bacteria • Domain Archaea • Eukaryotes • Domain Eukarya • Kingdom Protista • Kingdom Plantae • Kingdom Fungi • Chytridiomycota • Phylum Zygomycota • Phylum Basidiomycota • Phylum Ascomycota • Kingdom Animalia • Kingdom Animalia • Phylum Porifera • Phylum Cnidaria • Phylum Ctenophora • Phylum Platyhelminthes • Phylum Nemertea • Phylum Nematoda • Phylum Rotifera • Phylum Mollusca • Phylum Annelida • Phylum Arthropoda • Phylum Echinodermata • Phylum Chordata

4. Sponges Habitat Mostly marine, few freshwater sessile Suspension filter feeders Cellular level (lacks true tissues and organs) Body plan = asymmetrical Phylum Porifera

5. Although sponges lack true tissues they still carry out specific functions – at the cellular level • Porocytes: water canal • Pinacocytes: flat protective cells • Choanocytes: “collar cells” capture food (plankton) • Amebocytes: transport food; differentiate into other cells • Spicules: siliceous or calcareous skeletal structures

6. Poriferan body plans

7. Sponges, like many organisms, can reproduce asexually and sexually. Asexual budding Sexual broadcast spawn

8. Sponges, as simple as they are, show diverse adaptations and organization to varied environments Examples of these varied body plans include: • Tropical to temperate encrusting • Subtropical bath sponges • Deep water glass sponge

9. Are nearly all marine and include jellyfish, sea anemones, & coral which all share radial symmetry and specialized cells for predatory feeding Phylum Cnidaria (nigh-dare-ia)

10. Cnidarians are at the tissue level of organization …yet only two true derived tissues. • 2 layers • Epidermis and gastrodermis • Mesoglea is middle jelly layer rather than a true tissue Closer, but not yet… • Recall: Gastrulation (Infolding of the blastula) • Forming a primitive gut & embryonic tissues • Endodermlining of gut/organs • Mesoderm muscle, bone, connective tissue • Ectoderm skin, hair, nails, nervous tissue Cnidarian gut is described as gastrovascular cavity w/extracellular digestion

11. Cnidarians exhibit two basic body forms: medusa (swimming) and polyp (attached) Furthermore… • Polyp forms can be either solitary (individual polyps) or colonial (integrated of many polyp types) • Cnidarian life-cycles can include alternations of medusa and polyp generations.

12. Class Hydrozoa Greek: multi-serpent-headed water beast Individual polyps colonies of specialized polyps Feeding Reproductive Defense Phylum Cnidaria is organized into 4 classes: • Sessile colonies • Drifting colonies

13. Class Scyphozoa with dominant medusae stage Examples Sea Nettle Moon Jelly Upside-down Jelly Class Cubozoa Tropical Potent toxins

14. Solitary or colonial polyps w/out medusae stage Sea anemones Some with zooxanthellae symbionts Photosynthesizing protists Corals CaCO3 skeletons Environmentally valuable reefs Extremely susceptible to negative impacts Pollution, increased temp., etc Class Anthozoa

15. Comb jellies Marine planktonic predators that use 8 rows of ciliary combs or ctenes to swim Instead of cnidocytes, have tentacles with colloblasts to capture prey Adhesive, non-stinging cells Phylum Ctenophora

16. Flatworms Bilateral symmetry Organ level Except no circulatory Cerebral ganglia Simple brain Reproduction: Asexual (simple regeneration) Sexual Most are hermaphrodites Include free-living (self foraging) & parasitic lifestyles Phylum Platyhelminthes

17. This closed digestive system is described as an incomplete gut rather than a complete gut Acoelomic (w/out coelom or protective gut cavity) Flatworms have 3 distinct tissue layers – gave rise to a more complex digestive system

18. Parasitic flatworms find a host to feed from than spend much of their resources on reproduction Chinese liver fluke - Opisthorchis sinensis

19. Opisthorchis lifecycle

20. Schistosoma Female

21. Similar to this mammal tapeworm example, marine tapeworms are internal parasites to fish and marine mammals. “…as dense as seaweed forests, that live in the guts of sharks.”

22. Cestoda

23. Cestoda scolexes

24. Cestode proglottid 2 Testes Ovary Yolk gland

25. Ribbon worms “not flat, nor round” Advanced organ system over flat worms Circulatory system Complete gut Between Acoelomates & Pseudocoelomates Rhynchocoel: partial cavity around proboscis Eversible proboscis Phylum Nemertea

26. Roundworms Bit more space for more complex development Complete gut pseudocoelomates Varied environments, size, & lifestyles Aquatic to terrestrial Free-living to parasitic Marine sediments (feed on bacteria) Parasitic to most marine animals & many others Reproduction Primarily sexual One of the biggest marine parasites measures 13 meters and is two centimeters in diameter …found in the placenta of the sperm whale. Phylum Nematoda

27. Trichinella

28. Enterobius female

29. Ascaris Censored

30. Ascaris female x.s.

31. Ascaris male x.s.

32. Phylum Rotifera • Microscopic, yet multicellular, organ-level aquatic animals • Ciliated crown (“wheel”) to funnel food • Pharyngeal grinding structure (mastax) • Complete gut • Pseudocoelomates • Reproduce • Sexually …or… • Parthenogenesis (“virgin birth”) • Females  eggs  female offspring (w/out fertilization)

33. Very diverse group of soft body inverts that include Gastropods (Snails, slugs), Bivalves (oysters, clams, mussels), and Cephalopods (squid, cuttlefish, octopus) examples within this phylum are found in diverse environments: Marine, freshwater, moist land and, share characteristics such as… Open circulatory system central blood cavity rather than highly branched blood vessels Mantle for protection Secretes shell, provides space for gills and siphons Locomotive muscular “foot” Well developed Nervous system …in most Phylum Mollusca

34. Class Gastropoda “stomach footed” Mantle Tissue that secretes shell Radula Rows of rasping teeth for grazing Modified in predators

35. Single harpoon tooth evolved from rowed ancestors filled with paralyzing venom Conotoxins Medical value for specific neural & muscle treatment Addictive-free pain killers Cone shells

36. Clams, oysters, mussels… Suspension filter feeders Incurrent & excurrent siphons Spade-foot for locomotion Two valves (shells) secreted by mantle Held closed by powerful adductor muscles Class Bivalvia

37. Class Polyplacophora Chitons Graze on microalgae 8 overlapping plates Class Scaphopoda Tusk shells Open at both ends Deeper benthic sand/mud

38. Squid, octopus, cuttlefish, nautilus Shell: internal, external, or lacking Well developed nervous system Most adapted for active predatory lifestyle Class Cephalopoda

39. Class Cephalopoda (cont.) Muscular foot modified to arms &/or tentacles Siphon for locomotion Hydropropulsion Ink sac or gland defense Chromatophores Adjustable pigment cells Conotoxins in some

40. Most are separate sexes Some free spawners bivalves Most develop from: Trochophore larva Ring of cilia Veliger larva Ciliated mass Some parasitic larva Glochidia larva of some fresh water clams Reproduction

41. Segmented worms Earthworms Polychaetes Leeches Repetitive body parts Hydrostatic skeleton Flexibility and strength Coelomates Longitudinal & circular muscles Closed circulatory system Excretory organs Marine, moist land, and some freshwater Bilateral symmetry Some parasitic Phylum Annelida

42. Earthworm dissected

43. Class Polychaeta Adaptations to predatory lifestyle Eyes, tentacles, jaws, etc Coelom Protective gut cavity Parapodia w/setae Respiratory, nervous, and locomotion Nereis

44. phylogenetically placed between Mollusca and Arthropoda Trocophore larva segmentation Phylum Annelida

45. “walking worms” … or velvet worms Tropical predator Link between annelids and arthropods Walking appendages Lacks exoskeleton Antennae Soft segmented body, yet chitinous Arthropod-like circulatory system Phylum Onychophora

46. Examples (whether aquatic or terrestrial) include Insects, spiders, crabs, shrimp, centipedes – all of which possess a hard chitinous exoskeleton Replaced via molting Jointed bilateral appendages Segmented body Open circulatory system Many marine crustaceans Two pairs of antennae gills Phylum Arthropoda

47. Subphylum Trilobita

48. Chelicera First pair of oral appendages Scorpion pinchers Spider fangs Lack antennae Book gills or book lungs Typically four pairs of walking legs 2 body regions Cephalothorax & abdomen Subphylum Chelicerata

49. Class Merostomata

50. Class Arachnida