Vertebrate Adaptations Final Exam Study Guide

  1. Diving Adaptations
  2. Morphology of marine mammals
  3. Why do toothed (odontocete) whales have asymmetric skulls?
  4. Why are the cervical vertebrae of cetaceans compressed?
  5. How do marine mammals achieve laminar flow?
  6. what is the consequence of a blubber layer?
  7. where are the nipples and genitals?
  8. What is a mandibular stay, and why do baleen whales have them?
  9. Why do whales use dorsal-ventral undulation rather than lateral undulation?
  10. Physiology of marine mammals
  11. How is it possible the bottle-nosed whales can dive to depths of 2.5 mi for 2 hours?
  12. How do whales avoid the bends?
  13. How is the rib cage of whales modified for diving.
  14. Why do whales exhale before diving?
  15. How are rete mirabile and bradycardia related to diving?
  16. Whale bones are extremely oily, even after laying on a beach for a year. Before they can be put into a collection or displayed in a museum, the oils must be removed. What is the oil all about?
  17. Why is large size advantageous in diving?
  18. How does feeding in odontocetes and mysticetes differ?
  19. Why do grey whales not feed during their southward migrations to Baja?
  20. Evolution of Mammals
  21. Major themes in mammalian evolution
  22. Simplification of the jaw to involve only the dentary bone.
  23. jaw mechanics: effort and load arms, speed ratios and mechanical advantage.
  24. bite force.
  25. diversification of temporalis and masseter muscles.
  26. Evolution of the dentary squamosal jaw articulation.
  27. what happened to the quadrate and articular bones?
  28. in terms of sound conduction routes, why is this interesting?
  29. What is the significance of the synapsid jaw design?
  30. Evolution of the secondary palate.
  31. isolation of food from airway
  32. permits breathing while eating – important because of high metabolic rate.
  33. Diversification of dentition: be able to identify teeth associated with herbivory, carnivory, and omnivory.
  34. Modification of posture – loss of sprawling gait.
  35. Regionalization of vertebral column.
  36. Modification of pelvic and pectoral girdles.
  37. animals like cheetahs and horses use the scapula as a limb element, functionally increasing stride length.
  38. animals like elephants modify the pelvic girdle to handle graviportal limbs.
  39. Important point: mammals have a high cost of maintenance, and must feed the metabolic fires. Thus, much of their evolution is all about getting and processing food.
  40. Thermoregulation
  41. what came first, insulation or high metabolic rate.
  42. What are the constraints of hibernation?
  43. what is the thermal neutral zone?
  44. Mammalian evolution
  45. Are mammals monophyletic or diphyletic?
  46. Where did the marsupials have their evolutionary origin, and why are they now restricted primarily to Australia and New Guinea?
  47. Are monotremes mammals or reptiles?
  48. What reptilian characters do they have?
  49. What mammalian characters do they have?
  50. Describe the marsupial fauna of South America (historically and present). What happened to the bulk of this fauna, and why?
  51. Reproduction in marsupials and placentals is fundamentally different, even though marsupials do have a placenta.
  52. what problem did marsupials not solve (that is, why does parturition occur so soon after implantation of the embryo?)
  53. what is the advantage of delayed implantation?
  54. why do female kangaroos wait until relative old age to produce sons?
  55. I made the comment that much of marsupial evolution can be interpreted in light of foot morphology. How so?
  56. Marsupial morphological diversity mirrors that of placentals. Explain.
  57. Why were there no marsupial bats or whales?
  58. Evolution of Birds
  59. Understand the arguments about birds as dinosaurs.
  60. Physiological arguments (major player: Robert Baker)
  61. flight requires sustained aerobic metabolism, which reptiles do not have.
  62. did insulation come first, or did high metabolism come first?
  63. birds have 4-chambered hearts, but so do crocodilians.
  64. Flying reptiles lack a large keeled sternum, and are clearly not birds.
  65. Did flight evolve top-down or bottom-up (major player: Kevin Padian)
  66. Top-down: birds did not get into trees.
  67. Bottom-up
  68. Running and leaping to catch insects results in loss of speed and prey.
  69. Running involves asynchronous movement of pectoral appendages while flight involves synchronous movement of pectoral appendages.
  70. Misc
  71. Large dinosaurs probably did not run for the same reason that large mammals (elephants) do not run.
  72. Cost of locomotion goes down for large animals, but control issues become more important for small ones. Were the first fliers large or small?
  73. Archaeopteryx is the wrong age (Jurrasic) to be very helpful in the argument about the link between birds and dinosaurs.
  74. Protoavis is the right age, and if truly a birds, casts doubt on the birds as dinosaurs hypothesis.
  75. Mesozoic Reptiles
  76. What is the relationship between diapsid, anapsid, and synapsid reptiles?
  77. Describe the end-Permian mass extinction.
  78. What caused the extinction event.
  79. What proportion of the world’s species went extinct?
  80. How did land masses shift during this perioe?
  81. How did climate change?
  82. How did vegetation change?
  83. Describe the end-Cretaceous mass extinction.
  84. What caused the extinction event.
  85. What proportion of the world’s species went extinct?
  86. How did land masses shift during this perioe?
  87. How did climate change?
  88. How did vegetation change?
  89. How do dinosaurs differ morphologically from other reptiles?
  90. Ichthyosaurs and pleisiosaurs were not dinosaurs, but were contemporaraneous with them. How did their morphology relate to that of modern cetaceans.
  91. Modern Reptiles
  92. What is the relationship between lizards and snakes?
  93. How is body shape related to habitat use in snakes?
  94. What evidence do we have that snakes have a fossorial origin?
  95. Morphology of the eye.
  96. Limb loss.
  97. How does lizard morphology relate to locomotor mode and thermoregulatory mode?
  98. So what’s the deal with the pineal eye?
  99. Explain thermoregulatory strategies in reptiles.