Slide 1

The Animal Kingdom The Chordates Nancy G. Morris Volunteer State Community College Slide 2 Phylum Hemichordata Hemichordata (hemi = half; chordata= cord) acorn worm entirely marine adults show 3 of 4 basic characteristics: 1) pharyngial pouches 2) dorsal tubular nerve chord 3) tail evolutionary link between echinoderm and chordates ciliated larvum resembles tornaria larvum of echinoderms Slide 3 Phylum Chordata Subphylum Urochordata (uro = tail; chordata= cord) Subphylum Cephalochordata (cephalo = head; chordata= cord) Subphylum Vertebrata (vertebrate = backbone) Slide 4 Phylum Chordata All exhibit four chordata characteristics: 1) dorsal tubular nerve cord 2) notochord 3) pharyngial pouches 4) tail Deutrostomes chordates & echinoderms Slide 5 Anatomy of a Chordate Slide 6 Subphylum Urochordata sea squirts or tunicates notochord present only in free-swimming larvum notochord does not extend into head larvum is free-swimming but non-feeding adult is sessile filter feeder Slide 7 Subphylum Urochordata sea squirts or tunicate Campbell p 631 Settle after brief free-swimming larvum existence. Attaches at anterior end. Metamorphosis begins. Body turns 180 0. Tail, notochord, dorsal nerve cord, disappear. Slide 8 Subphylum Cephalochordata head cord lancelet or Amphioxus notochord present throughout life extends into head region shallow marine waters chordate characteristics developed and apparent in adult tail has blocks of muscles called myotomes adults resemble tunicate larvum Slide 9 Anatomy of a lancelet Slide 10 Cephalochordata: lancelet Slide 11 Subphylum Vertebrata General Characteristics: chordates with a backbone exhibit cephalization closed circulatory system neural crest (p. 633) Slide 12 Subphylum Vertebrata Agnatha (without jaws) lamprey parasitic bloodsuckers w/ rasping tongue hagfish mainly scavengers no paired appendages larvum resembles lancelet Slide 13 Agnatha: a sea lamprey Slide 14 Lamprey mouth Slide 15 Subphylum Vertebrata Chondrichthyes (cartilaginous fishes) flexible endoskeletons of cartilage strengthened by calcium granules sharks (internal fertilization) oviparous egg laying ovoviviparous retain fertilized eggs hatch within the uterus viviparous young develop in the uterus suspension-feeders (plankton) Slide 16 Phylum Hemichordata Hemichordata (hemi = half; chordata= cord) acorn worm entirely marine adults show 3 of 4 basic characteristics: 1) pharyngial pouches 2) dorsal tubular nerve chord 3) tail evolutionary link between echinoderm and chordates ciliated larvum resembles tornaria larvum of echinoderms Slide 17 Phylum Chordata Subphylum Urochordata (uro = tail; chordata= cord) Subphylum Cephalochordata (cephalo = head; chordata= cord) Subphylum Vertebrata (vertebrate = backbone) Slide 18 Phylum Chordata All exhibit four chordata characteristics: 1) dorsal tubular nerve cord 2) notochord 3) pharyngial pouches 4) tail Deutrostomes chordates & echinoderms Slide 19 Anatomy of a Chordate Slide 20 Subphylum Urochordata sea squirts or tunicates notochord present only in free-swimming larvum notochord does not extend into head larvum is free-swimming but non-feeding adult is sessile filter feeder Slide 21 Subphylum Urochordata sea squirts or tunicate Campbell p 631 Settle after brief free-swimming larvum existence. Attaches at anterior end. Metamorphosis begins. Body turns 180 0. Tail, notochord, dorsal nerve cord, disappear. Slide 22 Subphylum Cephalochordata head cord lancelet or Amphioxus notochord present throughout life extends into head region shallow marine waters chordate characteristics developed and apparent in adult tail has blocks of muscles called myotomes adults resemble tunicate larvum Slide 23 Anatomy of a lancelet Slide 24 Cephalochordata: lancelet Slide 25 Subphylum Vertebrata General Characteristics: chordates with a backbone exhibit cephalization closed circulatory system neural crest (p. 633) Slide 26 Subphylum Vertebrata Agnatha (without jaws) lamprey parasitic bloodsuckers w/ rasping tongue hagfish mainly scavengers no paired appendages larvum resembles lancelet Slide 27 Subphylum Vertebrata Chondrichthyes (cartilaginous fishes) flexible endoskeletons of cartilage strengthened by calcium granules sharks (internal fertilization) oviparous egg laying ovoviviparous retain fertilized eggs hatch within the uterus viviparous young develop in the uterus suspension-feeders (plankton) Slide 28 Subphylum Vertebrata Chondrichthyes (cartilaginous fishes) Rays & skates Bottom feeders mollusks & crustaceans Whiplike tail w/ venomous barbs (defense) Slide 29 Subphylum Vertebrata Chondrichthyes (cartilaginous fishes) Rays & skates Bottom feeders mollusks & crustaceans Whiplike tail w/ venomous barbs (defense) Slide 30 Subphylum Vertebrata Osteichthyes (bony fishes) Endoskeleton of hard calcium phosphate matrix Operculum- protective flap Swim bladder controls buoyancy Slide 31 Slide 32 Seahorse Slide 33 Subphylum Vertebrata Amphibia (two lives) first tetrapods transition to land still tied to water for respiration and reproduction Gills lungs (metamorphosis) Frogs, toads, salamanders, newts Slide 34 Slide 35 Slide 36 Subphylum Vertebrata Reptilia (Campbell, p. 644) (to creep) lizards, snakes, turtles, tortoises, Gila monsters, crocodiles, alligators first true land animal Scales, lungs, amniotic egg no feathers cold-blooded ectotherms (energy conservation) Slide 37 Slide 38 Hatching reptile Slide 39 Subphylum Vertebrata Fossil links Evolutionary link ?? between reptiles and birds: Archaeopteryx, a Jurassuc bird- reptile Clawed forelimbs Teeth Long tail w/ vertebrae Slide 40 Archaeopteryx Slide 41 Subphylum Vertebrata Aves (bird) feathered few flightless: ostrich, kiwi, emu breastbone with keel carina permitting flight jays, sparrows, warblers, etc Slide 42 Slide 43 Subphylum Vertebrata Mammalia (breast) Hair or fur of keratin Active metabolism = endothermic Efficient respiration w/ diaphragm Efficient circulation w/ 4-chambered heart Layer of fat Mammary glands, tooth differentiation Slide 44 Subphylum Vertebrata Mammalia (breast) Monotremes egg-laying mammals (Platypuses & echidnas spiny anteaters) Placental mammals Marsupial mammals kangaroo, opossum Slide 45 Slide 46 Marsupial & Placental Mammals Marsupial Placental