Which Factor Does Not Change Homozygous and Heterozygous Frequencies?

[moonman239]

Homework Statement

Which of the following is not a factor that causes changes in the frequency of homozygous and heterozygous individuals in a population?

a. mutations
b. migration
c. random mating
d. genetic drift

The Attempt at a Solution

I know that mutations is a factor, so cross out a.
I would say that migration is a factor, so cross out b. I am now left with two options: c. & d. This is where it gets confusing.

 

[moonman239]

OK, I know the answer. It's c. Random mating is not a factor, because in random mating males are statistically unbiased in choosing a female - in other words, they do not prefer one female over the other. The same can be said of the females.