Part A:
Beginning population:
- Total mice = 1000
- Number of mice with black fur (BB) = 200
- Number of mice with gray fur (BW) = 400
- Number of mice with white fur (WW) = 400
Calculations:
- p^2 (frequency of BB) = 200/1000 = 0.2
- q^2 (frequency of WW) = 400/1000 = 0.4
- 2pq (frequency of BW) = 400/1000 = 0.4
Ending population:
- Total mice = 1000
- Number of mice with black fur = 400
- Number of mice with gray fur = 400
- Number of mice with white fur = 200
Calculations:
- p^2 (frequency of BB) = 400/1000 = 0.4
- q^2 (frequency of WW) = 200/1000 = 0.2
- 2pq (frequency of BW) = 400/1000 = 0.4
Part B:
Based on the Hardy-Weinberg calculations, the allele frequencies have changed in the population between the beginning and ending time points. The frequency of the black fur allele has increased from 0.2 to 0.4, while the frequency of the white fur allele has decreased from 0.4 to 0.2.
This suggests that the population is evolving, as there has been a change in allele frequencies over time. One hypothesis for this observation could be that there was a change in the environment favoring black fur mice over white fur mice. For example, if the environment became darker due to factors like pollution or vegetation changes, black fur mice may have had an advantage in terms of camouflage and survival, leading to an increase in their frequency in the population.
In a certain population of mice, a single gene controls fur color. There are two possible alleles: B, which leads to a black fur, and W, which leads to white fur. Individuals with the genotype BB will have a black fur, individuals with the genotype WW will have white fur, and individuals with the genotype BW will have gray fur. Scientists recorded the fur color of 1,000 mice from the population. They found that 200 mice have black fur, 400 have gray fur, and 400 have white fur. Ten years later, the measurements are repeated. Again, they recorded the fur color of 1,000 mice. They found that 400 have black fur, 400 have gray fur, and 200 have white fur.
Part A:
Show the Hardy-Weinburg calculations for the beginning and ending populations. Include the values for the equation as well as the p and q values. Show your work.
Part B:
Use the Hardy-Weinberg calculation to explain if this population is evolving or not. Then propose a hypothesis about the environment of these mice that would lead to these observations.
Please answer correctly and in a relatively brief manner.
1 answer