Biology 156
Evolutionary Ecology
16 Feb 2001
Bob Podolsky
Week 6. Evolutionary physiology I
Study guide
After the first half of the module on evolutionary physiology, you should be able to:
Lecture 6.1: Experimental studies in laboratory populations
1. Give a simple description of the goals of evolutionary physiology
2. Give examples of some benefits of using lab experiments to examine the evolution of
physiological traits
3. Describe the procedure used by Partridge to create populations of flies that received exposure
to different selection pressures in the laboratory
4. Describe a hypothesis to explain the pattern of geographic variation in egg size among
populations of Drosophila
5. Explain how Azavedo et al. used Partridge's laboratory fly populations to test this hypothesis
6. Explain their graphical results, including the contributions of long-term selection and shortterm rearing conditions, and explain why their results were not likely due to genetic drift
7. Explain why their results cannot be used to infer that larger egg size is directly favored under
cold-temperature conditions
8. Explain the usefulness of the "performance curve" concept in studies of evolutionary
physiology, including the types of parameters that a performance curve can summarize
9. Distinguish between the procedures involved in "artificial selection" and "laboratory natural
selection", and explain how each of them can be used to test different kinds of questions
10. Explain the methods and evidence used by Huey et al. to test whether significant genetic
variation existed in populations of Drosophila for the ability to withstand high temperatures
11. Describe an experiment presented by Huey & Kingsolver to test the hypothesis that
development time in Drosophila would evolve in response to temperature conditions, and
explain whether their results were consistent with the hypothesis
12. Describe the results of Gilchrist et al. for the evolution of running speed in flies, and explain
what these results suggest about the evolution of physiology
13. Describe procedures used by Bennett at al. to set up E. coli populations that were initially
genetically identical but that differed in the selection pressures they experienced
14. Describe their experiments to test for the evolution of fitness, including their measure of
fitness and the trick they used to compare the fitness of ancestors against that of descendents
15. State their prediction about the relative rates of evolution expected under ancestral vs. novel
conditions, and describe whether their results were consistent with the predictions
16. Describe the patterns in their results concerning performance of bacteria at temperatures
other than those at which they had evolved, and explain why these results were unexpected
17. Describe the results of Partridge et al. concerning shifts in fecundity for populations of
Drosophila evolving under different temperature conditions
18. Explain what these results suggest about the evolution of performance curves for egg
production
19. Explain what Service et al. showed concerning shifts in tolerance for populations of
Drosophila that had been selected for certain life-history characteristics
20. Describe the goal of studies by Gibbs et al. on the evolution of physiology in Drosophila
21. Explain how their results support a plausible mechanism for the evolution of desiccation
tolerance
Lecture 6.2. Comparative studies in natural populations
22. Distinguish among three different models for the evolution of performance in response to a
change in environmental conditions
23. Given a hypothetical data set, explain why those data would tend to support one or another of
these models
24. Explain why testing for co-adaptation between two traits using comparative data can lead to
misleading results
25. Show graphically why information about the degree of relatedness may be critical for
drawing correct conclusions from such results
26. Describe the type of data that Huey and Kingsolver collected to test hypotheses concerning
the evolution of sprint speed in iguanid lizards
27. Explain what conclusions they drew from a graphical presentation of their results
28. State two alternative adaptive hypotheses to explain the correlation they found between
optimum temperature and critical maximum temperature for sprinting
29. Give a definition of endothermy and describe where it is generally found among vertebrates
30. Describe the general goals of Block et al.'s study of the evolution of endothermy, including
why she chose the particular taxonomic group for study
31. Describe two features necessary for the evolution of endothermy, and differences in such
features among three different groups within the scombrids
32. Explain what conflicting information existed concerning the number of times that
endothermy evolved independently in the scombrids
33. Describe the type of data that Block et al. collected to address the hypothesis that billfishes
and buttefly mackerels had evolved endothermy independently, and how those data
supported the hypothesis
34. Explain how three unique traits of tunas are functionally related: systemic endothermy, the
location of aerobic musculature, and swimming form
35. Explain what the data of Block et al. showed about the order in which these traits appeared in
the history of the scombrids, and what this order shows about the functional evolution of
body design