An active-learning lesson that targets student understanding of population growth in ecology
– Supporting File 3.
Supporting File 3. Clicker Questions and Student Responses.
Distribution of student responses to clicker questions. Correct answers are highlighted in blue and
underlined. There is no correct answer for CQ2. The percent of student responses for each answer
given as (percent of student responses for individual vote; percent of student responses following
peer discussion). For CQ5 students voted only following peer discussion.
CQ1: Which of the following statements describes the two study sites below?
A. Site 2 has a greater abundance and density than site 1 (16%; 4%)
B. Site 1 has a lower abundance but equal density to site 2 (10%; 2%)
C. Site 1 has a lower abundance but greater density than site 2 (70%; 93%)
D. The density and abundance are equal for both sites (4%; 1%)
CQ2: Select the growth curve that most resembles your prediction for barnacle population
growth?
A. linear (23%; 7%)
B. exponential (43%; 33%)
C. logistic (34%; 60%)
CQ3: Select the growth curve that most resembles the plot you generated from the data
provided.
A. linear (0%)
B. exponential (1%)
C. logistic (99%)
CQ4: The population growth rate (or change in population density) is:
A. increasing over time in all three growth curves (10%; 5%)
B. increasing over time in the linear and exponential growth curves only (15%; 9%)
C. constant over time in all three growth curves (1%; 0%)
D. constant in the linear growth curve and changes over time in the exponential and logistic
growth curves (74%; 86%)
CQ5: If r=2 per day and K= 80 barnacles per cm2, how does increasing the population size (N)
affect the rate of population growth (dN/dt) in the logistic growth curve?
A. As N approaches K, the population growth rate increases (12%)
B. As N approaches K, the population growth rate slows (76%)
C. As N approaches K, the population growth rate stays constant (12%)