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1. You are asked to work as an astrobiologist in the distantfuture. On Neptune’s moon Triton, you find a species of terrifyingand giant crustacean-like aliens that appear to live in completelyisolated populations within the nitrogen ice valleys on thesurface. As a famed xenobiologist that specializes in populationgenetics, you decide to compare and contrast two of these isolatedpopulations. Specifically, you are interested in the locusterror​​, which comprises three alleles T1, T2, and T3.
   1. Using state of the art technology, you can immediately infergenotypes on the spot! Below are the genotype frequencies for thetwo populations. Your non-biologist teammate speculates thatbecause genotypes containing T2 are so low in frequency in bothpopulations, T2 must be deleterious - and thus will soon beselected out of the populations. Are they right? Why or whynot?

genotype	T1T1	T1T2	T2T2	T1T3	T2T3	T3T3
pop. 1individuals	42	5	5	88	10	67
pop. 2. individuals	150	10	20	450	50	800

1. Someone on a rival ship accidentally brings a small batch ofhitchhiking aliens back to Earth. At least it’s not your fault!Unfortunately, they are reproducing, thus forming a newly isolatedpopulation that is terrorizing the planet. This new Earthpopulation of aliens is genotyped, and you find that they entirelylack the allele T3. Is this founder Earth population more likely tooriginally be from Triton population 1 or 2? Please show yourwork.

1. Regardless of your answer to part B, your colleague suggeststhat if​ ​ the new Earth population originally came fromTriton population 2, genetic drift is likely to play less of aneffect because of its large original population size (refer totable in part A). Are they correct? Why or why not?

1. You notice that terror​ ​ experiences selection onEarth. Because the Earth population completely lacks allele T3, youcan treat this population like a two allele locus, with genotypesand fitnesses listed below. What is the probability that T1 willfix or be lost due to drift alone? By contrast, what is theprobability that T1 will fix or be lost due to selection alone?Please show your work.

genotype	T1T1	T1T2	T2T2
frequency	0.10	0.10	0.80
fitness	1	0.90	0.90