If the egg-to-adult survival rates of genotypes A 1 A 1, A 1 A 2, and A 2 A 2 ar

Q: If the egg-to-adult survival rates of genotypes A 1 A 1, A 1 A 2, and A 2 A 2 ar

Genotypes A1 A1 A1 A2 A2 A2 Survival rate 90 85 75 Reproduction rate 50 55 70 Fitness 0.9 × 0.5 = 0.45 0.85 × 0.55 = 0.47 0.75 × 0.7 = 0.52 Relative fitness 0.86 0.9 1 Allele frequencies at equilibrium p = 0.48 and q = 0.52 Genotypes A1 A1 A1 A2 A2 A2 Survival rate 90 85 75 Reproduction rate 50 55 70 Fitness 0.9 × 0.5 = 0.45 0.85 × 0.55 = 0.47 0.75 × 0.7 = 0.52 Relative fitness 0.86 0.9 1

ID: 62623 • Letter: I

Question

If the egg-to-adult survival rates of genotypes A 1 A 1, A 1 A 2, and A 2 A 2 are 90, 85, and 75 percent, respectively, and their fecundity values are 50, 55, and 70 eggs per female, what are the approximate absolute fitnesses (R) and relative fitnesses of these genotypes? What are the allele frequencies at equilibrium? Suppose the species has two generations per year, that the genotypes do not differ in survival, and that the fecundity values are 50, 55, and 70 in the spring generation and 70, 65, and 55 in the fall generation. Will polymorphism persist, or will one allele become fixed? What if the fecundity values are 55, 65, 75 in the spring and 75, 65, 55 in the fall?

Explanation / Answer

Genotypes

A1 A1

A1 A2

A2 A2

Survival rate

Reproduction rate

Fitness

0.9 × 0.5 = 0.45

0.85 × 0.55 = 0.47

0.75 × 0.7 = 0.52

Relative fitness

0.86

0.9

Allele frequencies at equilibrium

p = 0.48 and q = 0.52