Question

15. Scientists were studying a rare type of bird found in the amazon rain forest. They noticed there were variations in beak size in the population. After many studies they were able to determine that the allele for large beaks was dominant (B) to the allele for small beaks (b). After careful observations they were able to conclude that population had 146 homozygous dominant individuals, 156 heterozygous individuals, and 200 homozygous recessive individuals.
a) What are the genotype frequencies for this population? (you must show work to receive credit)
b) What are the allelic frequencies for this population? (you must show work to receive credit)

Answer 1

(A)

Total population =146+156+200=502

Genotype frequency of BB= p2=no of homozygous dominant individual /total population =146/502=0.29

Genotype freq of Bb=no of heterozygotes/total popln=156/502=0.31

Genotype of bb=q2= no of homozygous recessive individual /total popln=200/502=0.40

(B)

Dominant B allele frequency =p= genotype freq of BB+1/2 (genotype freq of Bb) =0.29+1/2(0.31)=0.445

Recessive b allele freq=q=genotype freq of bb + 1/2(genotype freq of Bb) =0.40+1/2(0.31)=0.555