Readings: Chapters 1-2 from “Endless Forms Most Beautiful”
Informational Questions (bring your answers to these questions, as you will be responsible for answering one of them at the start of class):
1. What is meant by the term animal ”form”? What are some examples?
2. What are the 2 basic aspects of animal design? Give a human example of each.
3. What are serial homologs? Give an example from a human and an insect.
4. How is an animal constructed of repeating similar parts? Give an example from a vertebrate and an arthropod.
5. What is Williston’s law and how does it explain changes seen in the evolution of form? Give an example illustrating the law.
6. Where are the rules and directions that control animal design? What data support this idea?
7. What is the activity of Spemann’s “organizer” in controlling body form? How is it thought to function?
8. What is a homeotic transformation? Give an example of one.
Discussion Questions (we will consider these questions in class as a way to apply and explore the ideas presented in the reading):
(Group 1) 9. How did our discussions of cancer "explain the complex visible by the simple invisible"? (What is the complex visible and what is the simple invisible?)
(Group 2) 10. Do the examples illustrated by cycloptic sheep or Antennapedia flies represent a likely way that new species come into existence? Why? (Describe these examples and how they might contribute to new species, then critique.)
(Group 3) 11. What could explain why an embryo separated into two cells at the 2-cell stage can produce two viable animals but viable animals cannot be produced from individual cells when later stage embryos are separated (4- or 8-cell stage)? (Identify the key difference in cell bahavior and then speculate on ideas that could explain the difference.)
(Group 4) 12. Why would most people be surprised by (and likely question the validity of) the statement that "the same genes that control making an insect body and organs also controls the making of our bodies and organs"? (What is surprising about the statement and why would its truth be questioned...what would you want to know to judge its truth?)