Preview - From Ecosystems To Speciation

Get to know the model

The model on this page is of a population of bacteria in an environment where sugar is an energy source. Before we explore the phenomenon of genetic drift, let's get to know this model first. 

[* If the model is runs very slowly in your browser, use this GENETIC DRIFT MODEL for completing this lesson. You MUST have NetLogo installed on your computer to use the downloaded version of the model.]

Click 'SETUP' to initialize the model. Do NOT change any other parameters. 

Make sure that the parameter values are as following:

#-phenotypes = 5

initial-#-bacteria-per-phenotype = 6

left-resource -location right-resource-location
around a central point around a central point
left-resource-distribution right-resource-distribution
20% 20%

Run the model for 500 ticks for three times and answer the following questions.

Questions

Please answer the questions below.

Note down the number of bacteria of the following types in the left region and in the right region in each simulation run. 

Explain why there may be variation in population sizes in the three trials.

Change the resource distribution to 10% in the left and 80% in the right regions. Run the model. Describe the differences in the population growth in each region.

In the previous question, you were asked to compare regions with 10% and 80% resource distributions. Before you ran your experiment, did you make sure that the resource locations were the same for both the left and right regions? Why might this be an important step in order to talk about the differences between 10% and 80% resource distributions?

If, in the third question, you forgot to set the left and right region resource locations to the same thing (like "anywhere" or "horizontal strip"), go ahead and set them to the same thing and re-run your experiment. Using you new results, describe the differences in population growth between the two regions.

Notes

These notes will appear on every page in this lesson so feel free to put anything here you'd like to keep track of.