GEL 113 Homework 13 Answer sheet

Study Questions for Chapter 9: Introduction to Dinosaurs

Part I: True or False:

1.F 2.F 3.F 4.T 5.T 6.T 7.T

Part II: Multiple Choice:

1.B 2.D 3.A 4.D 5.D 6.C 7.C 8.C

Part III: Thought Questions:

1. The anatomical requirements for being classified as a dinosaurs are: erect posture, three or more sacral vertebrae, elongated ilium, perforated hip socket, inverted - L shaped head of femur, large fourth trochanter, prominent knee crest, straight ankle, astragalus overlaps tibia, digitigrade feet, reduced or absent fifth toe, long narrow shoulder blade, rear-facing shoulder joint, reduced or absent fourth and fifth fingers, S-shaped neck.

2. All are improvements in posture and running ability. They increased maneuverability and speed.

3. Ectotherms depend on external sources of heat, primarily sunlight, to keep their body temperatures elevated.

Endotherms have internal mechanisms to produce heat.

4. Evidence for endothermic dinosaurs includes: thermoregulation of nearest relatives, successful competition with mammals, aerobic anatomy, postures and hearts, large size, large relative brain size, bone texture, proportion of predator biomass, Artic and Antarctic Dinosaurs, oxygen isotopes in bone, insulative covering.

Evidence for ectothermic dinosaurs includes: overheating by very large endotherms, and nasal turbinates.