task Dobzhansky & Pavlovsky observed in a population box with the American Droso
ID: 211386 • Letter: T
Question
task
Dobzhansky & Pavlovsky observed in a population box with the American Drosophila species Drosophila pseudoobscura that an inversion polymorphism for the two naturally occurring inversion types Arrowhead (AR) and Chiricahua (CH) (as we consider here to be two codominant in an autosomal locus) following relative fitness (egg to adult survival) of the three karyotypes (genotypes):
One of the trials started with a population of adult flies where the frequency of AR inversion was 0.20 and the frequency of CH was 0.80, and with the same
frequency in the two sexes.
a) What is the expected frequency of AR and CH among the following generation adults if we assume random mating?
b) What is the expected equilibrium frequency after many generations?
c) If we assume that the selection only takes place in the larval stage and there is random mating, what will be the expected frequency of heterozygotes (AR / CH) and homozygotes (AR / AR and CH / CH) among eggs and adults at equilibrium?
Explanation / Answer
Answer:
If allelic frequencies are as given-
AR =0.2
CH =0.8
Next generation frequencies=
=Relative fitness x allelic frequency
For allele AR = 0.75 x 0.2 =0.15
For allele CH = 0.42 x 0.8 =0.336
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.