Exam I
Comparative Vertebrate Anatomy
Spring 2000
Name______________________________
Please read the questions carefully and be as specific as possible in your answers. Either fill in
the appropriate word in the blank or write one or two sentence answers.
Section I - Short Answer (3 points each).
1. The random process that produces genetic variation is ___________________, while the nonrandom process that determines what happens to organisms with these different genetic
variations is _______________________.
2. Digestive organs such as the stomach are derived from which primary germ tissue?
_________________________.
3. Good fossil series and/or important transitional forms exist for many vertebrate groups. Name
two examples. ________________________ and _______________________.
4. Define a monophyletic group.
5. Four features are usually given as characteristics of “vertebrates”. However, only three of
these are true synapomorphies of (found only in) the Craniata. Name these three.
________________________ , _________________________ and _______________________
6. Describe what is meant by allopatric speciation.
7. Name the vertebrate group with the largest number of living species ____________________.
8. Skip (material for this question was not was not covered this semester)
9. Name an important synapomorphy of the Gnathostomata ____________________________.
10. Give the formal name given to the group known as stem-reptiles _____________________.
11. With which of the following do Coelacanths (Actinistia) share a more recent common
ancestor. (Circle one) Mammalia Actinopterygii
12. Why are hagfishes (Myxinoidea) technically not considered members of the Vertebrata?
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13. We currently prefer to avoid using the names of some traditionally recognized taxonomic
groups such as aganatha, reptilia, and homeothermia. Why?
14. Describe two important characteristics of the Testudinata.
15. Crocodiles are more closely related to (circle one): birds or lizards
16. With respect to animal size and shape, the ______________________ is roughly
proportional to the square (2nd power) of body length, while the ____________________ is
roughly proportional to the cube (3rd power) of body length.
17. Members of a polyphyletic group are usually (mistakenly) grouped according to nonhomologous convergent/parallel/reversed similarity called _________________________.
18. Define paedomorphosis.
19. Name an individual who first proposed serious theories that evolution had occurred.
_______________________.
20. Somites are examples of what type of primary germ tissue _________________________.
21. Relative to body weight, the bones of a cow are (circle one) stronger or weaker than the
bones of a cat.
22. The morphological similarity between the marsupial Tasmanian wolf and placental dogs is
an example of what process? _____________________________.
23. The formation of the neural tube from the neural plate is called _______________________.
24. Give the formal name of the group commonly known as tunicates _____________________.
25. Radiometric dating requires than one know three quantities. These are 1) the relative
amounts of isotope and its decay product when the rock was formed, 2) the relative amounts of
isotope and decay product currently in the rock, and 3) ___________________________.
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Section II - Longer Answer
1. Use the data matrix below to draw the most parsimonious phylogenetic tree of the taxa.
Show where on the tree that each character changes. “p” means the character is present, “a”
means the character is absent, “a” is the ancestral state. Please make sure your final answer is
indicated (12.5 points).
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Character
Fur
Carnivorous
Canine teeth
Claws
Placenta
Large ears
Taxon 1
a
a
a
a
a
a
Taxon 2
p
a
a
a
a
p
Taxon 3
p
p
p
p
p
a
3
Taxon 4
p
p
p
p
p
a
Taxon 5
p
p
p
a
p
p
2. Draw and name each stage in development from the zygote through gastrulation. Using labels
or brief descriptions, indicate the important features of each stage or process (12.5 points).
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