Fun With Graphs. Quiz Yourself

Here are some questions that I have designed to let you know if you are understanding the graphs well enough to meet the course expected learning outcomes. I suggest that you do not try to answer these questions until you have thoroughly reviewed all of the information about the population ecology graphs. (I will put the answers for the multiple choice questions at the bottom of this post, for the others you need to find out whether your answers are correct or not).

1. What are the correct axes for a graph showing how population growth rate depends on population size in logistic growth?

a) x- N y- t
b) x- N y- dN/dt
c) x- dN/dt y- N
d) x- dN/dt y- t
e) x- N y- r

2. Which of the following best describes the graph that shows how the per capita growth rate varies over time in exponential growth?

a) the per capita growth rate decreases over time
b) the per capita growth rate increases over time
c) the per capita growth rate does not change over time
d) the per capita growth rate increases until it reaches a maximum and then decreases to zero when the population reaches the carrying capacity
e) the per capita death rate is initially very negative and gets less negative over time.

3. What would I ask to make you draw this graph?
a) show how the population size varies over time in logistic growth when the initial population size is much smaller than the carrying capacity
b) show how the population growth rate depends on the population size in logistic growth when the intitial population is much smaller than the carrying capacity
c) show how the population size depends on population size in logistic growth when the initial population size is much smaller than the carryuing capacity
d) show how the population size varies over time in logistic growth when the intitial population is much larger than the carrying capacity

4. What are the axes of a graph showing how the per capita growth rate depends on the population size in logistic growth?

a) x- logistic y- exponential
b) x- logistic y- r
c) x-N y-r
d) x-r y-N
e) x-N y-dN/dt

5. Which of the following is true when populations are at their carrying capacity?

a) N = 100 individuals
b) dN/dt = 0
c) b > d
d) b = d
e) b and d

6. Describe how the population growth rate varies over time in logistic growth when the intial population size is much larger than the carrying capacity.

7. Draw the graph that shows how the population size varies over time in logistic growth when the initial population size is much smaller than the carrying capacity.

Answers. 1.b, 2.c, 3.b, 4.c, 5.e