1. Flower color in the plant Lupinus terpensis is controlled by one locus, two alleles. In Maryland you find large populations of this plant (many thousands of individuals), which have blue flowers (AA), pink flowers (Aa) and white flowers (aa). However, you find small populations found on the numerous islands in the Cheasapeake Bay. These populations are almost always of one color, either blue or white, though the color differs between islands. Large populations on larger adjacent islands are polymorphic for flower color. The best explanation for this observation is that flower color on small islands is governed by:

A. mutation

B. natural selection

C. drift

D. heterozygote superiority

2. A population of beetles has a mean weight of 30 grams. Individuals of 12 grams are selected and allowed to interbreed, and their progeny have a mean weight of 21 grams. The heritability of weight in this population is

1. 0.18
2. 0.20
3. 0.25
4. 0.50
5. 0.80

3. A diploid population is polymorphic for 3 alleles at a single locus (A1, A2, A3):

allele A1 has a frequency of 0.5 and allele A2 has a frequency of 0.2. Assuming HW equilibrium:

a. What is the frequency of the third allele, A3?

b. What is the frequency of A2A3 heterozygotes?

In the above example, imagine that A1 is dominant to A2 which is dominant to A3, and A1A1 individuals have blue flowers, A2A2 individuals have pink flowers and A3A3 individuals have pink flowers.

c. What is the expected frequency of blue flowered individuals in this population?

4. In a population of birds that are blue, pink and white feathered, with blue and white the homozygotes

and pink reflects incomplete dominance of the heterozygote, you quantify the relative survivorship of the phenotypes as following:

80% blue feathered birds survive to reproduce

60% pink feathered birds survive to reproduce

40% white feathered birds survive to reproduce

A. What is the fitness of each phenotype and what is the amount of selection acting against each phenotype?

B. In another part of the species range you find that the relative survivorship of the phenotypes is different with

60% blue feathered birds survive to reproduce

100% pink feathered birds survive to reproduce

40% white feathered birds survive to reproduce

What is the fitness of each phenotype and what is the amount of selection acting against each phenotype?

If you find that this pattern of relative survivorship persists for many generations what PHENOTYPES do you think will be present after many generations of selection and in what proportion(s). Hint, similar to Sickle Cell example.

5. If you look about you will see height variation among your classmates? What factor(s) are the largest contributors to this height variation?

6. Which combination of parameters would result in the least change in a trait across generations. Assume a large population size:

i. strong selection, high heritability

ii. strong selection, low heritability

iii. weak selection, high heritability

iv. weak selection, low heritability