Final answer:
To calculate allele frequencies in a population, the Hardy-Weinberg model and its mathematical formula can be used, assuming no evolutionary forces act on the population. The frequencies for two alleles B and b can be calculated using genotypic counts in the population, and these frequencies are then used to predict the next generation's genotypic frequencies.
Step-by-step explanation:
To calculate the allele frequencies in a population, biologists often rely on the Hardy-Weinberg model, which provides a mathematical formula for predicting allele frequencies in a population at genetic equilibrium. If we assume the Hardy-Weinberg conditions are met, meaning no evolutionary forces are acting on the population, allele frequencies should remain stable across generations.
For a gene with two alleles, B and b, the frequency of each allele can be calculated using the following formula:
- p (frequency of allele B) = (2 × number of BB individuals) + (number of Bb individuals) / (2 × total number of individuals)
- q (frequency of allele b) = (2 × number of bb individuals) + (number of Bb individuals) / (2 × total number of individuals)
Applying this to a population of 50 individuals, where BB = 30, Bb = 10, and bb = 10, gives us:
- p = (2*30 + 10)/(2*50) = 70/100 = 0.7
- q = (2*10 + 10)/(2*50) = 30/100 = 0.3
Once the frequencies of each allele are calculated, they can be used to predict the frequencies of genotypes in the next generation using the equation: p² for BB, 2pq for Bb, and q² for bb genotypes.
By returning to the population in subsequent years and recalculating the allele frequencies, scientists can determine whether the population is in Hardy-Weinberg equilibrium or if evolutionary forces are at play.