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How confident are you that parental genotypes are not necessarily recreated in the offspring generation when every parent has an equal probability of surviving and reproducing? Please explain.
Any response in which you discuss elements about which you are confused or describe your understanding is acceptable.
Now let’s confirm that random reproduction produces the offspring genotypes we predicted based on the parental allele frequencies above. To do so, we will run a simulation in which the computer will randomly pick 50 pairs of alleles to represent 50 random fertilization events.
Are the genotype frequencies in the offspring generation produced by the simulation the same as those you predicted? Yes or no? Please explain.
Yes, they are. The AA , aa , and Aa genotypes occur with frequencies equal to 0.5625, 0.0625 and 0.375 respectively in the offspring generation of the simulation exactly as predicted.
Do the data support the prediction you made about the similarity between parental and offspring genotype frequencies in problem 6 above? Yes or no? Please explain using evidence to support your conclusion.
Best answers describe the prediction you made in problem 6 and how the data from the simulation do or do not support that expectation.
Imagine randomly mating the offspring generation just produced. Would you expect the genotype frequencies of their offspring to differ from their own? Yes or no? Please explain your conclusion and support it with evidence either logical or actual.
The genotypes frequencies should not differ between these two generations. You can support this using data collected from the simulation or by calculating the genotype frequencies one expects to see in their offspring as a result of random mating by these parents. This is illustrated below. F1 refers to the offspring generation just produced and F2 refers to their offspring.
To calculate F2 genotype frequencies, the first pieces of information we need are the allele frequencies of their parent's generation, F1.
We know that the allele frequencies of the F1 generation are identical to those of their parent's generation because every parent had an equal likelihood of surviving and mating (i.e. they were not subject to an agent of evolution). Consequently, in the F1 generation
Since the same allele frequencies and the same method are used to calculate the genotype frequencies for both the F1 and F2 generations, the genotype frequencies of these two generations must be identical.
To confirm this, review below:
and these calculations are identical to those we made to calculate the genotype frequencies for the F1 generation in problem 3 .
What do the conclusions to problems 9 and 6 suggest about the potential for similarity between parental and offspring generation allele frequencies when a population is not subject to any agents of evolution? Please explain.
In some cases, parental and offspring generation genotype frequencies may be the same and in others they may differ. The results demonstrate that if a parental generation, like F1, is the product of random mating and is itself not subject to any evolutionary pressures then its own genotype frequencies will be replicated in its offspring as observed in F2.
a. Finally, return to the simulation and click the box marked X, run it and record the results. Notice that the parent generation is identical to that in Figure 1. Review the results. Do you think that the offspring generation is the product of random mating? Why or why not? Please explain using data to support your conclusion.
b. What do these results indicate about the similarity between the allele frequencies of the parent and offspring generations? Why? Please explain.
a. The data suggest that the offspring were not the product of random mating because the genotype frequencies observed in the offspring generation differ greatly from those predicted Hardy-Weinberg and thus when the population is not subject to any agents of evolution.
b. The parent and offspring generations must have different allele frequencies because if they were the same, then the genotype frequencies of the offspring generation would be equal to those calculated by Hardy-Weinberg.
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