1. Vertebrate Evolution and Diversity Chapter 34

2. Vertebrates belong to phylum Chordata. Includes 3 subphyla, vertebrates and 2 phyla of invertebrates, urochordates and cephalochordates. 4 characteristics: notochord; dorsal, hollow nerve cord; pharyngeal slits; and muscular, postanal tail.

4. Notochord, present in all chordate embryos - flexible rod between digestive tube and nerve cord. Dorsal, hollow nerve cord develops in vertebrate embryo from plate of ectoderm that rolls into tube dorsal to notochord - can develop into spinal cord.

5. http://www-biol.paisley.ac.uk/courses/tatner/biomedia/jpegs/hypchrdb.jpg

6. Pharyngeal gill slits connect pharynx, just posterior to mouth, to outside of animal. Most chordates have muscular tail extending posterior to anus.

7. http://science.kennesaw.edu/biophys/biodiversity/animalia/cephal.gif

8. Tunicates Sessile marine animals that adhere to rocks, docks, and boats. Invertebrates - urochordates. Chordate characteristics are present as larva. Suspension-feeders.

10. http://www.aboututila.com/Reviews/Charlie-Johnson/Photos/Bluebell-Tunicates.jpg

12. Lancets Cephalochordates - have chordate characteristics in adult. Suspension-feeders.

14. Lancet

15. Vertebrates Neural crest, pronounced cephalization, vertebral column, closed circulatory system - subphylum Vertebrata. Neural crests start of formation of cranium; cephalization - collection of nervous tissue that forms brain.

16. http://bio1151.nicerweb.com/doc/class/bio1151/Locked/media/ch34/34_07NeuralCrest_L.jpg

17. Have appendicular skeleton, supporting 2 pairs of appendages (fins, legs, or arms). Can be made of either bone, cartilage, or both.

18. http://sciencecity.oupchina.com.hk/biology/student/glossary/img/appendicular_skeleton.jpg

19. Jawless vertebrate 2 classes of jawless vertebrates still living: Class Myxini (hagfish) and Class Cephalaspidomorphi (lampreys). Hagfish - skeletons made of cartilage making them flexible, but no backbone.

20. Hagfish

21. Lampreys - parasites with cartilage skeletons. Lack backbone - have notochord.

23. Jawed fish Jawed fish broken into 2 classes (extant). Chondrichthyes (cartilaginous fishes: sharks, rays), Osteichthyes (bony fishes: ray-finned fishes, lobe-finned fishes, lungfishes).

24. http://palaeo.gly.bris.ac.uk/Palaeofiles/Fossilgroups/Chondrichthyes/megalodon.jpg

25. Chondrichthyes - skeleton made of cartilage. Cartilaginous skeleton usually replaced by bone; chondrichthyes - process prevented. Fertilize internally; some lay eggs (oviparous), few give birth to live young (viviparous)

27. Osteichthyes - bony fish - endoskeleton made of bone. Bony fish have swim bladder not found in cartilaginous fish - helps control buoyancy of fish. Bony fish actually broken down into 3 groups: ray-finned fishes, lobe- finned fishes, lungfishes.

28. Ray-finned fishes

29. Lobe-finned fish

30. http://www.cartage.org.lb/en/themes/Sciences/Zoology/Biologicaldiverstity/AnimalsIII/coelacanth.jpg Lungfish

31. Tetrapods Tetrapods -land animals - walk on all fours - transition from water animals to land animals - amphibians.

33. Class Amphibia - amphibians - salamanders, frogs, caecilians (legless animals that burrow) Fertilization external - lay eggs. Most amphibians rely heavily on moist skin to carry out gas exchange with environment - still tied to water. Some adult frogs have lungs.

34. Caecilian

37. Amniotes Mammals, birds, reptiles, including turtles, lizards, snakes, crocodiles. Transition to land - adaptations were needed: amniotic egg, waterproof skin, increasing use of rib cage to ventilate lungs.

38. http://content.answers.com/main/content/wp/en-commons/thumb/f/fc/250px-Tortoise-Hatchling.jpg

39. Amniotic eggs of most amniotes have shell that retains water - can be laid in dry place. Inside shell of amniotic egg - several extraembryonic membranes that function in gas exchange, waste storage, and transfer of stored nutrients to embryo.

41. Reptiles Class Reptilia divided into 4 orders. Reptiles - several adaptations for terrestrial life not found in amphibians - leathery skin to prevent dehydration, lungs. Fertilization internal, eggs laid (amniotic eggs)

42. http://www.dnr.state.wi.us/org/caer/ce/eek/critter/reptile/images/turtleHatching.jpg

43. Reptiles - ectotherms - cannot maintain own internal temperature (cold-blooded). Turtles return to water to lay eggs; have not evolved since 1 st appearance. Lizards - most numerous reptiles.

46. Snakes - limbless reptiles - still have pelvic bones - evidence that they evolved from reptiles with legs. Crocodiles and alligators - largest living reptiles. Breathe through their nostrils that are pointed upward out of water.

49. Birds Birds - class Aves - broken down into 28 orders (few flightless birds) Birds evolved to have hollow bones to allow for flight and feathers. Modern birds - toothless - grind food in muscular gizzard near stomach.

51. Large brains of birds (proportionately larger than reptiles or amphibians) support very complex behavior. Birds - endotherms - metabolism allows them to regulate internal temperature.

53. Mammals Mammals - class Mammalia - identified by mammary glands. Most mammals give birth to live young after internal fertilization. Nutrition done via placenta. Most mammals capable of learning due to larger brains.

55. Monotremes - duck-billed platypus and echindas - lay eggs that have yolks to support embryo. Marsupials - born early in development crawl into pouch in mother to complete development. Eutherians - placental mammals.

56. http://cache.eb.com/eb/image?id=94548&rendTypeId=4

57. Echinda

58. http://marsupials.org/koalaalb.jpg

59. Opposum

60. http://www.ucmp.berkeley.edu/mammal/eutheria/rat.jpg

61. Primates - most advanced of eutherians. Opposable thumb characteristic of most advanced primates. Divided into 2 groups: prosimians (lemurs), anthropoids (apes, humans).

62. http://www.dumondconservancy.org/dc2005/images/web/troy%20originals/lemur8.jpg

63. http://www.dkimages.com/discover/previews/920/55048736.JPG

64. New World monkeys - arboreal (live in trees) - tails used for grasping.

66. Hominoid - great apes and humans collectively. Hominid - group closely related to humans. Human evolution included many adaptations - larger brains, ability to stand upright.

67. http://www.nhc.ed.ac.uk/images/vertebrates/primates/HominoidSkulls.jpg