Name: ______Period: _____
Natural Selection Simulation: Net Logo Bug Hunt – Speed
Purpose: In this activity, students will see a demonstration of Charles Darwin’s concept of Natural Selection.
PreLab: Use complete sentences to define the flowing terms:
1. Natural Selection: Briefly explain the three requirements for natural selection to occur:
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2. Microevolution:
3. Macroevolution:
Answer questions 4 -5 after reading the info (step III in the procedure)
4. Predators that chase their prey tend to eat what type of prey?
5. Predators that wait for their prey tend to eat what type of prey? Why?
Procedure:
I. Open Net Logo 5.3 * on your laptop. (* If needed: to Download Net Logo 5.3, go to: https://ccl.northwestern.edu/netlogo/download.shtml)
II. From the File menu, go to ‘Models Library’. Open the Biology folder, then the Evolution folder. Double click on the ‘Bug Hunt Speeds’ model.
III. Click the ‘Info’ tab and read about the Bug Hunt simulation. Answer prelab questions 4 and 5.
IV. Click ‘Setup’, then record the starting information (Average Bug Speed & Current Bug Population) in the space provided below.
V. You will follow the strategy of chasing down individual bugs with the bird cursor and clicking on them one at a time. Click ‘Go’ and try to catch as many bugs as you can while your partner times 1 minute.
VI. At the end of 1 minute, sketch the graphs for Average Bug Speed, Current Bug Population and Bugs Caught.
VII. Trade places with your partner and repeat Steps 4-5.
VIII. Switch to a different strategy of keeping the cursor still and clicking on bugs as they pass by to see if the result is different. To do this you must change to default settings so that the bugs do not avoid the prey by turning off the flee setting.
IX. Answer the Analysis and Conclusion questions using complete sentences.
Data:
Start Values:
Predator Strategy 1: Chasing bugs, then clicking on them one at a time
Trial 1 (1 minute):
Trial 2:
New Predator Strategy: Waiting for prey
Results:
Analysis & Conclusion Questions:
Use complete sentences to answer the questions that follow.
1. Summarize the distribution of speeds among the starting bug population (i.e. how many bugs of each speed are there at the start)?
2. When the predator is chasing individual bugs (first strategy), what happens to the average bug speed over time?
3. Explain why this happens. (Note that the population is staying constant. Every time a bug is eaten, a new bug is born that is the same speed as one of the surviving bugs in the population)
4. Is the effect on average bug speed different with a different predator strategy (e.g. sitting in one place waiting for bugs to happen by)? What effect did your new strategy have on the evolution of bug speed? Explain why.
5. Does the game simulate microevolution, macroevolution, or both? Explain.
6. How is the inheritance of traits simulated in this game? How closely does this match real inheritance (i.e. are offspring really identical to their parents)? What aspect(s) of real reproduction does the simulation leave out?
7. Do individual bugs in this simulation become faster or slower over time? If individual bugs do not change their speeds, how can the population’s average speed change over time?
8. How well does this game simulate real evolution? Describe one thing that it leaves out or oversimplifies. Can a simulation like this provide any insight into real evolution? Explain.