GEOL 104 Dinosaurs: A Natural History
Homework 4: Dinosaur Relationships
DUE: Mon. Nov. 4
Questions 1-3 refer to the sauropods shown below.
1. Match the sauropods (shown above) with the clade to which they belong:
Euhelopus: A. Macronaria
Brachiosaurus: B. Euhelopodidae
Diplodocus: C. Cetiosauridae
2. For two of the sauropods shown, describe the particular adaptations (at least two per genus) that allowed it to feed high in trees. For extra credit, describe the particular adaptations that allowed the third to feed high in trees.
3. Sauropods were gigantic animals. What selective advantages (name at least two) would there being in achieving such huge size? What disadvantages (name at least one) would this size produce?
Questions 4 – 6 refer to the ceratopsian cladogram below. The skeletal restorations are approximately to scale.
4. On the drawing above, label the following clades:
Ceratopsia Ceratopsidae Ceratopsinae Centrosaurinae Neoceratopsia
5. Indicate where the following shared derived characters originate on the cladogram above:
A. Horns B. Frill, obligate quadrupedality C. Rostral bone
D. Brow horns longer than nose horn E. Nose horn longer than brow horns
6. What general trend in size can you see in ceratopsian evolution?
Extra Credit) What is the sister group to the total clade shown above?
For questions 7 – 18, answer the questions referring to the illustrations immediately above them. Where given a choice in brackets, circle the correct answer.
7. The above tail (in dorsal view) is from a [ stegosaur | ankylosaur ].
8. The primary function for this tail was [ to obtain food | as active defense | to help it run faster ].
9. The skull shown above is from a [ oviraptorosaur | coelophysoid ].
10. This taxon had a diet primarily of [ meat | plants ].
11. The manus above is from a(n) [ tyrannosaurid | ornithomimosaur ].
12. This taxon is a [ ceratosaur | carnosaur | coelurosaur ].
13. The skull above is from a [ pachycephalosaur | ceratopsian ].
Extra Credit) What was the probable function of the domed head?
14. The skull above is from a [ hadrosaurine | lambeosaurine ].
15. The skull above is from a(n) [ marginocephalian | ornithopod | thyreophoran ].
16. The skull above is from a(n) [ ornithischian | saurischian ].
Extra Credit) The diet of the dinosaur shown above was most likely [ meat | plants ].
The pelves above are in left lateral view.
17. The [ left | right ] pelvis is from a saurischian.
18. The [ left | right ] pelvis is from an ornithischian.
Extra Credit) Of the two types (saurischian and ornithischian), which shows the derived condition of the backwards pointing pubis? .
Extra Credit) What is the probable function for the backwards pointing pubis in this group of dinosaurs?