Characteristics that differentiate animals: Levels of organization (cells, tissues, organs, organ systems) Body symmetry (none, radial or bilateral) Germ layers (endoderm, mesoderm, ectoderm) Body cavity (acoelom, pseudocoelom, coelom) Type of body: Segmentation (repeating parts), cephalization (getting a head), limb formation (legs, flippers, wings) Systems (digestive, circulatory), Reproduction (asexual or sexual), Homeostasis (body temperature) Type of skeleton (endo- or exoskeleton)

1. Phylum Porifera (Sponges) Levels of Organization Specialized cells Body Symmetry Asymmetrical (none) Germ Layers Absent Body Cavity ---- Embryological Development Segmentation Cephalization Incomplete digestive system – filter feeders Invertebrates Asexual and sexual reproduction Examples: sponges

2. Phylum Cnidaria (Jellyfish) Levels of Organization Specialized cells, tissues Body Symmetry Radial Germ Layers Two Body Cavity Acoelom (gastrovascular cavity digests and circulates nutrients) Embryological Development ---- Segmentation Absent Cephalization Invertebrates Examples: jellyfish, hydra, sea anemones, coral

3. Phylum Platyhelminthes (Flatworms) Levels of Organization Specialized cells, tissues, organs Body Symmetry Bilateral Germ Layers Three Body Cavity Acoelom (Gastrovascular cavity digests and circulates nutrients) Embryological Development Protostome Segmentation Absent Cephalization Present! Can you see the head of these flatworms? Invertebrates Flattened body Includes many parasites Examples: planaria, tapeworms, many parasites

4. Phylum Nematoda (Roundworms) Levels of Organization Specialized cells, tissues, organs Body Symmetry Bilateral Germ Layers 3 germ layers Body Cavity Pseudocoelom Embryological Development Protostome Segmentation Absent Cephalization Present (look for the mouth) Have a mouth and anus Sexual reproduction Ex: Ascaris is a parasitic roundworm that lives in intestines of pigs and humans

5. Phylum Annelida (Segmented worms) Levels of Organization Specialized cells, tissues, organs Body Symmetry Bilateral Germ Layers Three Body Cavity True coelom (complete digestive system) Embryological Development Protostome Segmentation Present (ring-like segments) Cephalization Present Primitive circulatory system Reproductive openings Ex: earthworms, leeches

6. Phylum Mollusca (Clams, Snails) Levels of Organization Specialized cells, tissues, organs Body Symmetry Bilateral Germ Layers Three Body Cavity True coelom Embryological Development Protostome Segmentation No segmentation Cephalization Present Some can move with a muscular foot Chitons Snails, slugs Squids and octopi Clams and oysters

7. Phylum Arthropoda (Insects) Levels of Organization Specialized cells, tissues, organs Body Symmetry Bilateral Germ Layers Three Body Cavity True coelom Embryological Development Protostome Segmentation Segmented body – head, thorax, abdomen Cephalization Present Most successful animal phylum based on species diversity and distribution Invertebrates Jointed appendages Exoskeleton Examples: insects, spiders, butterflies, crustaceans (lobster, crab), grasshoppers

8. Phylum Echinodermata (Starfish) Levels of Organization Specialized cells, tissues, organs Body Symmetry Radial (as adults) Germ Layers Three Body Cavity True coelom Embryological Development Deuterostome Segmentation Absent Cephalization Absent (as adults) Invertebrates Arms, and tube feet  Complete digestive tract Closed circulatory system Ex: Starfish, sea urchin, sand dollar, sea cucumber

9. Phylum Chordata (Chordates) Mostly vertebrates (includes invertebrate chordates too) Animals in this phylum have a dorsal hollow nerve cord (eventually becomes spinal cord) Don’t necessarily have a bony vertebral column Simple circulatory system Examples of some invertebrate chordates: sea squirts, tunicates Ex. of vertebrate chordates in upcoming stations (10-17) Sea squirts Tunicates

10. Subphylum Vertebrata (Vertebrates) Key Characteristics: - Notochord replaced by cartilage or bony vertebral column - 7 Major Classes within Vertebrata: Agnatha (jawless fish) Chondrichthyes (cartilaginous fish) Osteichthyes (bony fish) Amphibia (amphibians) Reptilia (reptiles) Aves (birds) Mammalia (mammals)

11. Class Agnatha (Jawless Fish) No jaws No scales – have SKIN! 7 or 12 gill slits Continuous median fin Examples: Hagfish (body made of collagen - rare) Lamprey (has vertebrae) The hagfish is black

12. Class Chondrichthyes (Cartilaginous Fish) Flexible skeleton of cartilage Jaws and paired appendages Lateral line sensory system Scales 5 gill slits Ex: sharks, rays

13. Class Osteichthyes (Bony Fish) Bony skeleton Operculum (flap) protecting gills and allows fish to breathe without swimming Scales Different position of fins and mouth Swim bladder (derivative of lung) Ex: Eels, salmon, carp, catfish, walleye, cod

14. Class Amphibia Tadpole  Larva with functional gills Eggs deposited in water Undergo metamorphosis Develop lungs Four limbs Ex: frogs, toads, salamanders, newts

15. Class Reptilia Internal fertilization Amniotic egg No larval stage Breathe air (lungs) Ectothermic (cold blooded) Epidermal scales Ex: turtles, crocodiles, snakes, lizards

16. Class Aves (Birds) Forelimbs modified to wings Feathers Hollow bones Lay shelled eggs Endothermic (warm blooded) Ex: eagles, blue jays, pelicans, etc.

17. Class Mammalia Mammary glands (produce milk) Hair or fur Endothermic (warm blooded) Examples: humans, cats, dogs, squirrels, horses, etc.