Name:____________________
Worksheet 5: Growth of Populations
Chapter 22
1. Define population ecology. What types of questions does this discipline answer?
2. Review the biological hierarchy (Section 1.3) and the term species (Section 19.3). Which
species concept is most applicable to population ecology and why?
3. Consider the following populations of humans with the number of people and total area:
#1
200
People
#2
10 sq km
1000
People
100 sq km
a. Which has the highest population size?
b. Which has the greatest population density?
4. What four (4) factors determine whether a population increases or decreases in size?
5. In the simplest population growth model, the change in the population size over time is a
function of the number of individuals in the population and the unrestrained increase in
population size.
a. What type of population growth does this describe?
b. What assumptions are made with this model?
c. Describe an example of a population that exhibited this type of growth:
6. An alternative model considers factors that may restrain population growth.
a. Define habitat. Briefly explain how habitat influences population growth.
b. Define carrying capacity. Describe how population growth is limited by carrying
capacity.
c. What environmental factors limit population growth?
7. Which of the two population growth models is most commonly observed? Why?
8. Differentiate between density-dependent and density-independent factors. Provide
specific examples for each.
9. Describe a situation in which the population sizes of two species are tightly linked.
10. Most populations do not exhibit the regular patterns of growth discussed previously.
Identify and briefly describe a population that exhibits irregular fluctuations. What
factors might contribute to these patterns?
11. Consider the human population.
a. What major factor contributed to our rapid population growth?
b. What factors limit the growth of our population? Of these factors, which are
density-dependent?
c. What pattern of population growth (exponential, logistic, cyclical, irregular, or
other) do you think the human population will exhibit and why?