Marine Animals II. The Chordates OCN 201 Biology Lecture 7 Arthropods Segmented Worms The Animal Chordates Family Tree Mollusks Echinoderms Round Worms Cnidarians Ctenophores Flatworms Sponges Placozoa Ancestral Protist Chordate Tree Invertebrates Vertebrates Chordate Features Chordate Features Tunicates Salps • Pelagic or benthic • Often colonial • Suspension feeders Ascidians (sea squirts) Larvaceans Lancelets • Small fish-like, No Jaw • Suspension feeder • Can swim, but usually stays partly buried Amphioxus The Major Fish Groups • Jawless fishes (Agnatha) • Cartilaginous fishes (Chondrichthyes) • Bony fishes (Osteichthyes) Jawless Fish Lamprey (Parasite) • No jaws • No appendages • Cartilaginous • Parasites or Scavengers Hagfish (Scavenger) Jawless Fish Hagfish slime defense Cartilaginous Fish (Chondrichthyes) • Sharks, Skates and Rays • Skeleton of cartilage • Have jaws • Carnivores or Planktivores Cartilaginous Fish: Planktivores • Planktivores (filter feeders) are largest • Gaping mouth with small or no teeth • Gill rakers • Manta Ray (8 m across!) Gill Rakers • Whale Shark (up to 17 m long!) Planktivores Whale Shark Manta Ray Cartilaginous Fish: Carnivores Cookie-Cutter Shark Photo: NOAA Cookie-Cutter Shark Wounds Goblin Shark Photo: Mike Spalding vis WIRED magazine Bony Fish (Osteichtyes) • 22,000 species Stout Infantfish • From about <1 cm to 11 m • Surface to ≥ 8370 m deep Oarfish Herbivores Herbivores (algae) Planktivores (Filter Feeders) Anchovies H O Sardines 2 filter: gill rakers mouth gill opening gut Used by the most successful groups Carnivores Parrot Fish Tuna Mola mola Most Massive bony fish: Up to 1300 kg and 3 m tip to tip Feeds on gelatinous zooplankton Reptiles, Birds, and Mammals Sea Turtles LARGEST: • Loggerhead • Leatherback • Hawksbill • Olive Ridley • Green Sea Turtle (Honu) > 2 m long up to 1300 lbs Other Marine Reptiles Tropical West pacific/Indian Ocean • Crocodile - one living marine species • Snake - 50 species Marine Birds • albatross, shearwaters • gulls and terns • pelicans, cormorants, frigate birds • penguins Marine Mammals (Class Mammalia) Carnivora - polar bears, sea otter, pinnipeds Sirenians - dugongs and manatees Cetaceans - whales and dolphins CARNIVORA Pinnipeds (seals and sea lions) Polar Bears Sea Otters Ursus maritimus Enhydra lutris Sirenians • dugongs and manatees • Herbivores - eat sea grasses • Near shore inhabitants of warm tropical waters • About 13,000 alive today - recently taken off the endangered species list Cetaceans Includes the whales, dolphins and porpoises Two Cetacean Suborders: • Mysticetes (11 living species) – large – baleen whales - filter feeders – 2 blowhole openings • Odontocetes (about 67 species) – smaller – toothed whales, dolphins, and porpoises – 1 blowhole opening Mysticetes (baleen whales) Use complex vocalizations or “songs” for communication Baleen (Mysticetes) • Large mouthfuls of water are filtered through the baleen plates trapping plankton, small fish and other animals Humpback Bubble Net Mysticete Migration patterns • Great whales migrate: - Warm, tropical waters in the winter (for breeding) - Colder, polar waters in summer (for feeding) Humpback Whale Migration Humpbacks around Hawaii (Mid-December to May) Odontocetes (toothed whales) Carnivores Use squeals chirps and clicks for communication, echolocation and stunning of prey.