Question

Information for question # 21,22, and 23. Allele frequencies at a wing length locus are measured for a natural population of a migratory cricket species as P(A₁) = 0.4 and Q (A₂) = 0.6. Observed genotype frequencies in the field population are shown below. Compute the expected frequency of the three genotypes if the population is in Hardy-Weinberg Equilibrium for this locus?  

                                     Observed frequency                  Expected frequency       Show your work

             A₁A₁     =          0.28                  

             A₁A₂     =          0.22                  

             A₂A₂  =             0.50                  

21. The expected frequency of the genotypes are:            

a) A₁A₁  =0.25              A₁A₂  = 0.50                 A₂A₂  = 0.25

b) A₁A₁  =0.28              A₁A₂  = 0.22                 A₂A₂  = 0.50

c) A₁A₁  =0.16              A₁A₂  = 0.48                 A₂A₂  = 0.36 - CORRECT ANSWER

d) A₁A₁  =0.36              A₁A₂  = 0.48                 A₂A₂  = 0.16

             e) None of the above

22. Compute the value of the inbreeding coefficient (F) for this population. The inbreeding coefficient is  

A) 0

B) 0.043

C) 0.43

D) 0.54 - CORRECT ANSWER   

E) 1

23. Based on your calculation is there evidence for assortative mating in this population?

a) Yes                           b) No                c)  Not enough information

I just need help with number 23, PLEASE explain how you got the answer!

Thank you!

Answer 1

There's evidence fir assortative mating in this population. So the right option is Yes.

Reason :-

In assortative mating, partners prefers someone who is phenotypically similar to them. Like Red colour bird will prefer red color bird instead of a pale bird even though both are same species.

In cases of assortative matings, the frequency of Heterozygous is less than expected because since one phenotype is preferring same phenotype while other phenotype is preferring the same phenotype.

So there's less mingling of two different alleles.

In your question, Expected Heterozygote was 0.48 but observed is 0.22. This is very less than expected.

Same with Homozygous A1. Observed is 0.28 instead of expected 0.16. Homozygous A2 is 0.5 instead of 0.36. Both the homozygous genotypes have increased. Thus they are preferring the same phenotype. This means there's assortative mating in the population.

I hope the explanation was clear understandable.