Card Set Information

2014-05-29 00:11:54
bio geo

Show Answers:

  1. 4 modes of air travel
    • passive flight
    • parachuting
    • soaring
    • active flight
  2. Dispersing spores (passive flight) evolved in the __ era
    • Early Paleozoic
    • Oldest spores = Ordovician
  3. Insects with flight evolved in the __ period
  4. Parachuting vertebrates evolved in the __ period and were diverse in the __ period
    Permian; Triassic
  5. Pterosaurs evolved in the __ period.
    Late Triassic
  6. Birds evolved in the __ period
  7. Bats evolved in the __ period
    early Tertiary
  8. Why did flight evolve in animals?
    • escape predators
    • catch prey
    • move from place to place
    • access to new food sources/unoccupied niche
    • social reasons?
  9. The first animals to fly were
    • arthropods: flying Hexapods (common by late Carboniferous)
    • flight only occurs in adults
  10. origin of flight in insects
    • possessed walking legs and exites (homologous with exopods?)
    • evolved from gill/swimming legs
    • didn't sacrifice "walking limb" for wings
  11. In insects, wings were pre-adapted for
    • swimming
    • Small wing aspect ratios require rapid strokes.
  12. primary requirements/demands of active flight
    • strong, yet light body (skeleton)
    • streamline/aerodynamic body
    • modified pectoral girdle capable of power stroke
    • modified forelimb capable of supporting useful wing
  13. Cursorial Flight Hypothesis among birds
    • began by running and flapping from the ground
    • Terrestrial theropods used wings to catch prey "insect nets" or
    • flapping and fighting during social activities
    • problem with hypothesis: Theropods could climb.
  14. Arboreal Flight Hypothesis among birds
    • began by climbing and jumping from trees
    • Theropods climbs trees to avoid predation and forage
    • problem with hypothesis: Climbing damages feathers on terrestrial theropods.
  15. 1st vertebrates capable of true/powered/active flight
    Pterosaurs (Late Triassic)
  16. locomotion of Pterosaurs on ground
    • ability to walk is debatable:
    • Fused pelvic girdle suggests bipedal locomotion.
    • Scrawny hind limbs with "sideways" posture suggests quadrupedal locomotion
  17. origin of birds
    evolved by the Late Jurassic from Theropod dinosaurs
  18. There was a low diversity of birds until the __ period
    • late Cretaceous
    • (very successful group)
  19. A good candidate for sister taxa of birds are the
  20. Dromeosaurids originated in the __ period
    Late Cretaceous (younger than first birds)
  21. Similarities between first birds and Dromeosaurids
    • feathered
    • bipedal
    • big brained
    • cursorial
    • terrestrial (couldn't fly)
  22. general adaptations of birds
    • hollow bones (pneumatic)
    • keeled sternum
    • short stout humerus
    • wing supported by elongated radius and ulna
    • feathers
    • fused clavicle AKA furculum
  23. first "true bird"
    Archaeopteryx (Late Jurassic)
  24. similarities and differences between Archaeopteryx and modern birds
    • similarities: feathers and furculum
    • differences: fingers on wings, small sternum
  25. purposes of developing wings
    • display = social activity
    • thermoregulation
  26. characteristics of Archaopteryx that fit the Cursorial hypothesis
    • tail feathers not for flight
    • fused clavicle (furculum)
    • claws for catching prey
  27. characteristics of Archaopteryx that fit the Arboreal hypothesis
    • retroverted hallux capable of perching
    • fore limb clawed phalanges could be used for climbling
  28. bird evolution
    • Birds show a gradual increase in flying during early evolution.
    • Later birds improved on the basic flight adaptations and become better flyers.
  29. swimming/diving birds
    • Penguins and other divers use the basic stroke "flying underwater"
    • Other birds use their feet for diving
  30. The hypothetical ancestor of bats would have been
    a nocturnal, insectivorous, arboreal glider
  31. flight adaptations of bats
    • keen senses (echolocation or good eyesight)
    • modified pectoral girdle
    • reduced radius with enlarged humerus and ulna
    • clawed fingers
    • uropatagium: membrane between hind limbs for stabilization and gliding
  32. bat wing
    membrane supported by the arm and several elongated fingers, which help produce greater thrust