Natural Selection

Essay by PaperNerd ContributorCollege, Undergraduate October 2001

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"Random mating" is when mating is random, individuals pair by chance not by phenotype or genotype. In non-random mating allele frequency do not change in the population. In all of our populations the allele frequencies changed over generations, a sign for random mating. Also if a population under goes non-random mating, you will see a decline in the heterozygous genotypes and an increase in both homozygous genotypes. There is no such pattern in our natural selection exercise. Thus, random mating is present in the natural selection exercise.

        If there is no gene flow in a population, then there is no exchange of genetic material between two different populations of the same species. Each group studied one population per environment, so there was no possibility of genetic material being exchanged, since there was no other population to exchange genetic material with.

        No mutation in a population means that there should not be a change in the nucleotide sequence of a pre-existing allele, so that the process creates a different allele.

In our natural selection exercise no alleles were created in any population, the same two alleles were present from the beginning of the exercise till the end.

        If there is no natural selection in a population, then we will not see a certain allele being favored, so that in increase in frequency in the population. This assumption of the Hardy-Weinberg equation is not meet by our natural selection exercise. If you look at any one of the five populations, there is always a certain allele that is favored by natural selection, and increase in frequency over generations.

PART 4         Based on the results of population I and II, I would expect there to be a see saw effect in the allele frequencies. Meaning that for each generation one allele frequency might...