# How to calculate gene / allele frequency & relative fitness

1. A population of gerbils has three color morphs, color is determined by a single locus.

BB is BLACK, Bb is BROWN, bb is yellow.

Black has a 25% chance of surviving to adulthood, and has 10 offspring as an adult

Brown has a 50% chance of surviving to adulthood, and has 5 offspring as an adult

Yellow has a 25% chance of surviving to adulthood, and has 5 offspring as an adult

What are the relative fitnesses of each genotype?

If the initial frequency of the B allele is .75, what is the frequency of that allele after one generation?

https://brainmass.com/biology/genetic-recombination/how-to-calculate-gene-allele-frequency-relative-fitness-71743

#### Solution Preview

Since, Black has a 25% chance of surviving to adulthood, and has 10 offspring as an adult

Hence, Black has a 100% chance of surviving to adulthood, and has 10 * 100/ 25 = 40 offspring as an adult

Similarly, Brown has a 100% ...

#### Solution Summary

In Hardy-Weinberg population, allelic frequency can be calculated if the initial frequency of the gene is known. Similarly relative fitness of allelic constitution can be known provided number of surviving allel in a population is known.