Gene R controls ear shape in rabbits. Rabbit ears can be round (dominant), pointed (recessive), or floppy (heterozygous). The allele frequency of R is 0.8 in a population of rabbits. Assuming the population is in Hardy-Weinberg equilibrium for the R gene, what is the expected frequency of pointy-eared rabbits?

According to Hardy- Weinberg equilibrium principle,The allele frequency and the genotypic frequency will remain constant for generation after generation in absence of external evolutionary influences like mutation, genetic drift,natural selection etc.

According to Hardy- Weinberg equilibrium,

If the allele 'R' denotes the dominant allele then the frequency of the allele will be=f(R)=p (Round ear)

The allele 'r' denotes the recessive allele then the frequency of the allele will be=f(r)=q (Pointy ear)

Then, the genotype frequency will be,

p+q=1 (The allele frequency of 'R' is 0.8=p)

Then, 0.8+q=1

or, q=1-0.8=0.2