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Assignment 5
 

Assignment 5

The experiments that you have conducted so far were designed to help you learn about the many factors and interactions that can influence the size and growth of a population. Since ecosystems are affected by random events such as changes in weather, applied ecologists must often make an assessment of "extinction risk." They do this by constructing simulation models similar to PopEcoLab and running multiple simulations. This group assignment is designed to have you use PopEcoLab to evaluate extinction risk by running multiple simulations (e.g., 100 simulations) and noting the frequency with which a population becomes extinct.

Design experiments to study how this risk of extinction changes for a combination of parameters such as clutch size and life span. Examine how the extinction risk varies for different time windows, for example, 100 years, 200 years, and so on. Be systematic in your experimental design. Devise a plan to divide your investigation among different members of your group and run multiple simulations for each experiment. Tip: If you go to the Initial Population screen and click on the Multiple Run Mode button, you can set the number of runs to 10. This will give you ten independent simulations that you can examine by using the spinners on the output screen.
1 .       Did the results of your experiments support your hypothesis? If not, reformulate a new hypothesis and carry out additional experiments.  



2 .       Explain how the experimental conditions you set up were responsible for your results. Once you think you have an explanation for your findings, design and carry out additional experiments to support or refute your thesis.  








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