Ecology 203, Exam I
, October 14, 1998 Name ______________________________ (1 pt, spelling counts)Rules:
Read carefully, work accurately and efficiently. Answer all questions to the best of your ability. If you get stuck on a question move on and return if you have time. Good luck!Multiple Choice. (Circle the one correct answer). (3 pts each; 24 pts total)
1. Relative to populations of equal size in a single habitat, metapopulations are
2. Introduced species: (submitted by fellow student)
3. The change in seasons is due to:
4. Higher latitudes (both north & south) are colder than lower latitudes (near equator) because
5. Evolution, the change in gene frequencies over time, occurs by:
6. Sexual dimorphism is caused by (submitted by fellow student)
7. The change in density of a chaotic population is (submitted by fellow student)
8. The following is not an assumption of the Hardy-Weinberg Law: (submitted by fellow student)
True-False circle T for true, F for false (3 pts each; 15 pts total).
T F Natural selection, the most important mechanism leading to evolution, can be observed in our lifetime.
T F Populations comprised of "r-strategists" grow and reproduce quickly. (submitted by fellow student)
T F Poikilotherms have no mechanisms to control their body temperature.
T F Populations that exhibit source-sink dynamics are in decline (population is decreasing).
T F Andrewartha and Birch studied a thrips population and concluded that the population was regulated primarily by weather. They did acknowledge, however, that some biotic factors may operate at times but that, in general, abiotic factors explained most of the variance in their multiple regression model used to predict population numbers.
Graph the relationship between realized population growth (dN/dt) and population size (N) under density-dependent regulation. Include the Allee Effect and identify all equilibrium points as stable or unstable. Label the axes. (5 pts)
Short answer (Complete TWO of the three): (6 pts each; 12 pts total)
1a. Given that you know Nt = No e rt, r = 0.01 annually, and that No for an insect population today is one hundred individuals. Assuming annual reproduction with non-overlapping generations what will the population be in 100 years?
1b. How many years does it take for this population to double in size (or when will Nt = 2 No assuming you know Nt = No e rt)?
2. A population has the following life table:
X lx bx
0 0.5 1
1 0.0 1
and No = 10, N1 = 5
Plot the number of individuals in both age
classes 0 and 1 over then next three years.
3. What are the four, observable characteristics of natural selection?
Short answer (Choose any
FOUR of the following six questions): (3 pts each; 12 pts total)1. Describe the mark-recapture method for estimating population size (the equation is required).
2. Why are models are useful in ecology?
3. Give an example of something that exhibits a stabilizing type of selection. (submitted by fellow student)
4. What are the constraints on the number of eggs laid by female birds (briefly discuss constraints for both low and high egg production).
5. What are some of the problems faced by organisms in high (or low you choose) temperature environments? (submitted by fellow student)
Define any TWO of the following (identify those you are defining). (5 pts each; 10 pts total)
Physiological ecology Niche
Null hypothesis
The Kill Curve
Statistical significance
Mimicry
Ecology
Fill in the missing word or phrase for
FOUR of the following. (3 pts each; 12 pts total)Design an experiment (10 pts)
The level of CO2 in the atmosphere has been increasing for several decades and is expected to double by the year 2050. Plants need CO2 to grow. Design an experiment to test the effect of increased CO2 on the height of goldenrod. Do not provide an introduction, results, justification, or poetry. Assume that you have the necessary equipment and time for this experiment. Feel free to provide a diagram of the experimental design if this reduces how much you have to write. (Continue on the back of this sheet if you must)