STUDENTS: Write answers to the exercises neatly and hand or mail them to your instructor after the session is completed.

Exercises

1. Draw a series of graphs illustrating the minimal conditions for a plausible predator-prey model; i.e., plot R_h and R_c as function of H and C under conditions 1-4.
2. Prove that the L-V prey equations with logistic intraspecific competition do not satisfy conditions 2, 3 and 4 for a plausible model.
3. Mathematically define the zero-growth isoclines for the L-V model with logistic intraspecific competition amongst prey. Draw the isoclines and plot an approximate trajectory starting at a particular location in phase space.
4. Run the PAS Lesson PL2 and summarize what you learned.

Questions

1. Why use mathematical models for studying predator-prey dynamics?
2. What is the difference between an instantaneous and an overall hunting equation?
3. What is the law of mass action?
4. Distinguish between a differential and a difference equation.
5. What are the three main approaches to modeling predator-prey interactions.
6. Write the Lotka-Volterra equations and define their components and parameters.
7. What are the dynamic properties of the L-V model?
8. How can one plot a dynamic trajectory in predator-prey phase space?
9. What are the minimum set of attributes of a biologically plausible predator-prey model?
10. Describe how Lotka derived the logistic equation?
11. What are the assumptions underlying the logistic model?
12. What is an R-function?
13. What effect does logistic prey growth have on the dynamics of the L-V model?
14. What is the carrying capacity of the environment?
15. Describe how the carrying capacity can be deduced from the logistic model and how it is inserted into the equation.