2. CLASS REPTILIA Henry Tsai Stefanie Frank

3. * waterproof/scaly skin * ectothermic * Oviparity * Found on every continent except Antarctica. General Characteristics

4. Other Characteristics * Bilateral Symmetry * Coelomate * Deuterostome * Closed, double circulatory system

5. Evolutionary History * First appeared in Carboniferous period. * Vastly diversified in Permian Period. * Dominant in Mesozoic Era

7. Hylonomus (310 MYA)

9. Mammal-like reptiles

11. Mesozoic:THE AGE OF REPTILES

12. Reptiles gave rise to

13. Advantages over amphibians * Can live with little water * Internal Fertilization * shelled egg with amnion * No Larval stage * Stronger legs * better Respiratory and circulatory systems. *Waterproof skin

15. The Four Surviving orders Crocodilia

16. chelonia

17. Carapace Plastron

18. Squamata

20. Rynchocephalia (tuataras)

21. Embryology *Amniotic Egg –*Amnion –*Yolk sac –*allantois –*chorion –*albumen (egg white)

23. Physiology *Waterproof (usually scaly) skins –*made of Keratins *Respiration: Mostly Lungs *Excretion: solid, Nitrogenous wastes (urea)

27. Circulatory system * Most have 3 chambered hearts (2 atria and 1 ventricle) * Direct blood away from lungs to conserve energy. –* Advantages: doesn’t need to breath all the time, can raise body temperature faster.

30. Respiratory system * Large lungs with alveoli * Some only have 1 functional lung * reptile breathe by expanding rib cage.

31. Nervous system * Larger cerebrum than amphibians of same size * well developed olfactory lobe * Good eyesight * tympanum for hearing * Jacobson’s organ * Heat sensitive pits (some snakes)

32. Crocodile brain

37. Diet/food acquisition * carnivores (scavengers and active hunters) * omnivores * Herbivores

38. Reproduction *Hemipenis *Internal Fertilization * Oviparity * Ovoviviparity * Viviparity * Some have parental care –Ex. Crocodiles, king cobra

40. Locomotion: Snakes

41. Sea snakes do swim

42. Locomotion: turtles/tortoises

45. Locomotion: Lizards (and tuatara)

46. Locomotion: Crocodilians

48. Reptile Defenses * Claws and jaws (brute force) * chemicals (poisons/foul odors) * autotomy * carapace * bluff *camouflage * Run! Run! Retreat! Retreat!

49. Alligators

50. Python (non poisonous)

51. Spitting cobra

52. Stinkpot

53. Iguana (autotomy)

54. Pond turtle

56. Frilled necked Lizard

57. So how can we exploit them? * Pets * Food/medicine * Fashion (skin) * Entertainment * Vector control * Important members of various ecosystems

58. The End Or Is it?