Biology of the Vertebrates Study Questions F2014
Note: These study questions are not comprehensive. They are meant to supplement your lecture notes as you review them, and alert you to the ways in which you should be thinking about the material, and formulate questions to test yourself. Exams will NOT be limited to the material highlighted in these questions, or their formats, so your lecture notes and handouts should be your primary reference.
Lecture 1 (26 August 2014)
1. Dr. Jockusch mentioned that holistic, integrative studies have largely gone by the wayside, in lieu of increased research specialization on levels of organization rather than organisms. What is the purpose of studying "the biology of the vertebrates?"
2. What is the most basic function of an individual vertebrate? Name two of the other functions mentioned in class, and explain how they influence this most basic function. Give a specific example of each.
3. How do iguanas breathe differently than humans, and how does this affect an iguana's ability to capture food?
4. Explain what a "trade-off" is, using the Hydromantes salamander's ballistic tongue as an example.
Lecture 2 (28 August 2014)
1. Are sharks more closely related to birds or hagfish?
2. When Dr. Jockusch says, "We [humans] are all bony fish," what does she mean?
3. Define "synapomorphy," and name one for echinoderms and chordates.
4. What is a "sister group?"
5. On a phylogenetic tree, which conveys more information, the order of the taxa listed on the tips, or the arrangement of the branches? Why?
6. Is the ancestral state for the Testudines, aquatic or terrestrial?
7. Which of the 12 extant vertebrate lineages don't occur in a marine environment? And of those, which have never lived in a marine environment?
Lecture 3 (2 Sept 2014)
1. What does it mean that Urochordates have an open circulatory system? How is that different than a closed circulatory system and what is the function of the circulatory system?
2. Hagfish are often called "living fossils." Why?
3. What is the difference between an atriopore and an anus?
4. What is a novel characteristic of the lancet's gut, and what is its significance?
5. How do Urochordates and Cephalochordates filter water?
6. Draw a simple phylogenetic tree with vertebrates, Urochordates, and Cephalochordates, in addition to the Deuterostome phyla.
7. Which traits of Urochordates and Cephalochordates are synapomorphies for vertebrates?
Lecture 4 (4 Sept 2014)
1. What are two synapomorphies that unite Myxinoidea and Petromyzontoidea? What are two synapomorphies for vertebrates?
2. The oldest freshwater lamprey fossil is considerably more recent than the oldest marine lamprey fossil. What can we infer from this?
3. Name a characteristic of hagfish that is an example of a "lost" trait. Why might organisms "lose" traits their ancestors once had?
4. Both lampreys and hagfish have caudal fins, with one major difference. What is this difference, and why is it important?
5. Compare the hypothetical "ancestors" of both chordates and vertebrates. What are the major adaptations that occur between these two hypothetical species?
6. What are the major differences in reproductive strategy between lampreys and hagfish? What are the advantages and disadvantages of each?
7. Explain the difference between the Myxinoidea and Petromyzontoidea's keratinized "teeth" and how they use them to acquire food.
Lecture 5 (9 Sept 2014)
1. What are the morphological and molecular hypotheses for the placement of Petromyzontoidea on the phylogenetic tree of vertebrates? Describe how these different hypotheses change our understanding of the evolutionary history of at least one trait.
2. What about why aren't agnathans monophyletic? And why does this mean that the group can't be placed on a phylogenetic tree?
3. From what we discussed in class, give two examples of what we can learn by studying the fossil record.
4. What are conodonts and where are they currently placed on the vertebrate tree? give two traits that justify this placement, and explain why the current placement is uncertain.
5. What characteristics of the Metaspringgina identify it a vertebrate, and not a more basal chordate?