Marine Animals II. The Chordates
OCN 201 Biology Lecture 7 Arthropods Segmented Worms The Animal Chordates
Family Tree Mollusks
Echinoderms mouth first anus first Round Worms
Cnidarians
Ctenophores Flatworms
Placozoa Sponges Ancestral Protist Echinoderms Sea Stars Sea Cucumbers
Sea Urchins Brittle Stars Crinoids
Looks like radial symmetry, but is not really Bilateral symmetry echinoderms is more obvious in the larval stages
Echinoderm Larva
Bilateral symmetry 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 Chordate Tree Invertebrates Vertebrates 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 Chordate Phylogeny Invertebrates Vertebrates 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!) • Whale Shark (up to 17 m long!)
Gill Rakers 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 www.conserveturtles.org 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 Mammals
Features: • Endotherms (warm-blooded) • Breathe Air • Have Hair • Live Young • Milk Production in Females 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 Humpback Whale Humpbacks around Hawaii (Mid-December to May)
• Great whales migrate:
- Warm, tropical waters in the winter (for breeding)
- Colder, polar waters in winter (for feeding) Odontocetes (toothed whales)
Carnivores
Use squeals chirps and clicks for communication, echolocation and stunning of prey