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Dr. sisko studies the flowering plant Mimulus cardinalis in an experimental population of size 1000 that grows in acidic soil. The color of the flower in this plant is determined by a single locus with two co-dominant alleles A1 and A2. Laboratory observations show that seeds from red and pink flower plants survive with equal success in the acidic soil but seeds from plants with white flowers (A2A2) have decreased fitness with a selection coefficient of s=0.2

Phenotype Red (A1A1) Pink (A1A2) White (A2A2)
# plants (adults) 200 300 500
Fitness 1.0 1.0 1-s

1) Calculate the allele frequencies in the next generation before selection.

2) Calculate the allele frequencies in the next generation after selection.

3) Calculate the genotype frequencies in the next generation after selection.

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Nelly Stracke
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