In a certain population of finches, a single gene controls beak length. There are two possible alleles: S, which leads to a short beak, and L, which leads to a long beak. Individuals with the genotype SS will have a short beak, individuals with the genotype LL will have a long beak, and individuals with the genotype SL will have a medium-length beak. Scientists measure that in this population of 1,128 total birds, 321 birds have short beaks, 562 have medium-length beaks, and 245 have long beaks.
Ten years later, the measurements are repeated. This time, there were 1,346 birds in the population. 452 have short beaks, 699 have medium-length beaks, and 195 have long beaks.
Use the passage to answer the question.
Based on the original data collected from the population of 1,128 birds, what fraction of the population would be expected to have the SS genotype if the population was in Hardy-Weinberg equilibrium?
0.466
0.534
0.285
0.217
To determine the expected fraction of the population with the SS genotype in Hardy-Weinberg equilibrium, we need to calculate the frequency of the SS genotype within the population.
The frequency of the SS genotype can be calculated by dividing the number of individuals with the SS genotype by the total population. In the original data, there were 321 birds with short beaks, which would represent the SS genotype. Thus, the frequency of the SS genotype can be calculated as:
(321 birds with SS genotype) / (1,128 total birds) ≈ 0.285
Therefore, the expected fraction of the population with the SS genotype would be approximately 0.285 or 28.5%.
Therefore, the correct answer is:
0.285