In a population of 1000 fruit flies, 360 have red eyes and the remainder have sepia eyes. The sepia eye trait is recessive to red eyes. How many individuals would you expect to be homozygous for red eye color if the population is in Hardy-Weinberg equilibrium?

Explanation:

Calculations:

Let q²= homozygous recessive

p²=  homozygous dominant  

2 pq heterozygous

q² for this population is 640/1000 = 0.64

q = √o.64 = 0.8

so, P= 1- q  

= 1- 0.8 = 0.2

The homozygous dominant frequency = p² = (0.2)(0.2) = 0.04

Therefore, you can expect 4% of 1000, or 40 individuals, to be homozygous dominant.