wombat_answers - work(4 pts Ne= 4NmNf(Nm Nf Nm= 2 and Nf=...

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8a) Consider the Wombat. You are fortunate to discover a second breeding colony in New South Wales, Australia, previously unknown to science. You want to make predictions about how much genetic diversity will exist in the population over the next few decades. You guess from the number of breeding individuals that the effective population size is about 30 individuals. How much heterozygosity should exist in the population about 50 years from now (5 generations) if the current observed heterozygosity is 0.50 average across 10 loci. (6 pts) (Show all work) Ht/Ho= (1-[1/(2Ne)])t Or Ht = Ho (1-[1/(2Ne)])t Ho = 0.50, Ne = 30 and t=5 Ht = 0.50 (1-[1/(60)])5 Ht = 0.4597 8b) Unfortunately, you discover that most of the males are not fertile and consequently, there are 15 breeding females but only 2 breeding males. What is the revised effective size? Assuming that you can equalize the number of breeding males and females in the next generation, and return the effective size to 30, what is your revised estimate for the loss of heterozygosity? (Show all
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Unformatted text preview: work) (4 pts) Ne= 4NmNf/(Nm+Nf) Nm= 2 and Nf= 15 Ne= 4(2*15)/(2+15) Ne= 120/(17) Ne= 7.0588 Over five generations (two will be accepted also), use the harmonic mean 1/Ne=1/t 1/Ni or 1/Ne=1/5(1/7.06 +1/30 +1/30+1/30+1/30) = 18.18 (2gen=11.49) Ht = Ho (1-[1/(2Ne)])t Ht = .5 (1-[1/(2*18.18)])5 Ht = 0.43 (2gen=0.46) 8c) Finally, you hope to counteract the loss of variation by establishing some gene flow between the two existing wombat colonies. You observed an Fst of 0.15 between the two existing colonists. How many migrants per generation are implied by this degree of differentiation? (Show all work) (4 pts) N e m =(1- .15)/4* (.15) N e m = 1.4167 or about 1.4 migrants per generation are needed to restore gene flow. Some useful equations: Fst= (Ht-Hs)/Ht D12= Ht - Hs Fst =1/(4Nem + 1) N e m =(1- F st )/4F st Ht/Ho= (1-[1/(2Ne)])t F = (2pq-Ho)/2pq E(n)= m- (1-p)2Ne Ne= 4NmNf/(Nm+Nf) 1/Ne=1/t1/Ni...
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This note was uploaded on 03/05/2008 for the course EE BIOL 116 taught by Professor Rundel during the Winter '08 term at UCLA.

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