A general outline of the material on marine reptiles:
Turtles
Related to terrestrial archosauromorphs
First turtles about Late Triassic
Diverse in Jurassic and Cretaceous
Up to 3 m long, 4 m flipper span
Crocodiles
Also derived from terrestrial ancestors
Separate invasion of aquatic habitats to parasuchids (phytosaurs)
Got huge (15+ m, 18 tons)
Ichthyosaurs
Like dolphins with vertical tail
Known as fossils for over 200 years
Up to 15 m (Nevada, including mass stranding of 37 animals)
Mostly Jurassic, One survivor in Cretaceous
Live Birth
Sauropterygians
"Nothosaurs" -> Later ->
Plesiosaurs (to 12 m., most smaller)
(Early Jurassic -> Late Cretaceous)
Pliosaurs (to 12 m., like an ichthyosaur)
Mosasaurs
Big monitor lizards (to 10 m.)
Review Questions
1. What are the five main groups of aquatic reptiles that lived in the Mesozoic Era? What evidence is there that each of these groups reinvented the aquatic environment separately?
2. How are these reptiles similar to each other? How do they differ? (Be sure to also consider the last section on air breathing at sea.) How can one come to the conclusion that many of the similarities are due to convergent evolution, not due to common ancestry.
3. How does an ichthyosaur compare to a dolphin?
4. How does a plesiosaur compare with a pliosaur? Which of these (if any) is more closely related to a mososaur?
5. Compare and contrast wind pollination with pollination by animal visitors. When did each arise, what is the fossil record corresponding to each type, and what ecological settings are favorable or unfavorable to each type?
6. Compare and contrast pollination with seed dispersal. How do the interests of animal visitors differ with respect to these two aspects of plant reproduction? How do different animal visitors differ in their effectiveness as seed dispersers?
7. What was the extent of ecological by angiosperms during the Cretateous? What was their role after the K-T extinction event? How has it changed during the Cenozoic Era? What are some possible explanations for their increasing successes.
8. What does the diversification of social insects (Hymenoptera) have to do with flowering plants? Why might this have favored flowering plants over other plants that were dominant at the time?
9. Why do terrestrial plants produce lots of exotic chemicals?
[Go to Previous: Review Questions for HOL Chapter 13]
[Go to Next: Review Questions for HOL Chapter 15]
[Go to History of Life listing for Chapter 14]
[Return to Honors 301T Home Page]