3. Suppose that a lizard species eats only one type of insect and the populations follow Lotka- Volterra dynamics. The intrinsic growth rate of insects in the absence of predators is 0.2 per week, and the mortality rate of the lizards in the absence of insects is 0.05 per week. The capture efficiency rate is 0.002, and the efficiency at which insect biomass is converted into predator biomass is 0.2. Draw a phase plane plot of lizards interacting with these insects. Indicate the following information on the phase plane plot. a. Draw and label the insect zero growth isocline. (Be sure to indicate the population size). b. Draw and label the lizard zero growth isocline. (Be sure to indicate the population size). c. If the population of insects start with 75 insects and 125 lizards, what will be the trajectory of each species? d. Draw the long-term population trajectories.

3. Suppose that a lizard species eats only one type of insect and the populations follow Lotka- Volterra dynamics. The intrinsic growth rate of insects in the absence of predators is 0.2 per week, and the mortality rate of the lizards in the absence of insects is 0.05 per week. The capture efficiency rate is 0.002, and the efficiency at which insect biomass is converted into predator biomass is 0.2. Draw a phase plane plot of lizards interacting with these insects. Indicate the following information on the phase plane plot. a. Draw and label the insect zero growth isocline. (Be sure to indicate the population size). b. Draw and label the lizard zero growth isocline. (Be sure to indicate the population size). c. If the population of insects start with 75 insects and 125 lizards, what will be the trajectory of each species? d. Draw the long-term population trajectories.

Biology 2e

2nd Edition

ISBN:9781947172517

Author:Matthew Douglas, Jung Choi, Mary Ann Clark

Publisher:Matthew Douglas, Jung Choi, Mary Ann Clark

Chapter45: Population And Community Ecology

Section: Chapter Questions

Problem 2VCQ: Figure 45.10b If the major food source of the seals declines due to pollution or overfishing, which...

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