Question

please show work Nerodia sipedon insularum is a species of the Northern Water Snake that lives on islands in the western part of Lake Erie. This snake exhibits polymorphism (many color forms) and can be described as Banded (BB), intermediate (Bb) and unbanded (bb). The mainland populations of this snake are all banded. The islands have sandy shores which the snakes reside compared to rocky shores of the mainland. In 1980-1984, Richard King conducted a study of mark recapture to look at the numbers of each of these morphs of snakes and for the Island of Pelee this was the population size: Banded: 71 individuals; Intermediate: 80 individuals; Unbanded 20 individuals. Give the genotypic frequencies for each morph and then give the allele frequencies for this population.

Answer 1

The genotypic frequencies for the banded, intermediate, and unbanded morphs of the Nerodia sipedon insularum population on the Island of Pelee are 0.4152, 0.4678, and 0.1169, respectively. The allele frequencies for the B and b alleles are 0.4202 and 0.5798.

Step-by-step explanation:

In order to determine the genotypic frequencies for each morph of the Nerodia sipedon insularum population on the Island of Pelee, we need to first calculate the total number of individuals in the population. Adding up the numbers of each morph, we have a total of 71 banded, 80 intermediate, and 20 unbanded individuals. The total population size is 71 + 80 + 20 = 171 individuals.

To calculate the genotypic frequencies, we divide the number of individuals with a particular genotype by the total population size. The genotypic frequencies for each morph are as follows: Banded (BB): 71/171 = 0.4152, Intermediate (Bb): 80/171 = 0.4678, Unbanded (bb): 20/171 = 0.1169.

To calculate the allele frequencies, we can use the Hardy-Weinberg equation. Since there are two alleles (B and b), the sum of the allele frequencies should equal 1. We can use the genotypic frequencies to calculate the allele frequencies. The allele frequencies for the B and b alleles are as follows: B: (2 * 71 + 80) / (2 * 171) = 0.4202, b: (2 * 20 + 80) / (2 * 171) = 0.5798.