readings - introduction - exercise instructions - homework - instructor hints

Mayr, E. 1959. Where Are We?

- Start by finding a partner and counting out 20 white beans and 20 speckled beans into a lunch bag. For consistency, abbreviate the bean types as follows:
- White Beans: W
- Speckled Beans: S
- You will be assigned one of the following :
- Randomly draw 4 beans from the initial population (this is your breeding population) in the bag. These four beans are the only ones that reproduce from the initial population.
- Each of these beans has 10 offspring.
- Create the first generation from the offspring.
- The population size should be 40.
- Calculate the frequencies of the W and S alleles in the first generation.
- Repeat and monitor the changes in gene frequencies over ten generations.
- Repeat the same procedure as in part one with the population size = 40, breeding population size = 10, and initial genotype frequencies = 0.5. In this case, each parent will produce 4 offspring so that the population size remains at 40 from the generation to generation.

- Compile separate tables for the two different breeding population sizes on the blackboard.
- List the frequencies of W alleles at each generation for all replicate populations in your section.
- Prepare one graph using the class data. For each of the two different breeding population sizes, plot the frequency of the W allele on the x-axis and the number of generations on the y-axis.

Opaque containers to serve as source pools for selection of beans.

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