Problem Set 2
Due Friday January 19
(1) A researcher buys 500 homozygous winged and 500 homozygous wingless flies
from the Jackson Labs and puts them into a population cage. Winglessness
is recessive. The researcher's fly food is too gooey; wingless flies
have a 20% chance of becoming stuck in the food and dying.
- What are the allele and genotype frequencies of the initial population?
- What are s and h for the population cage system?
- What will be the allele and genotype frequencies of the adult flies of
the next generation? (Assume that all death due to stickiness happens
before the flies are fully adult.)
- Sketch the likely long-term allele frequencies of this population cage.
(2) The researcher's supervisor explains about sticky food, and the
researcher corrects her food formula at a point where the frequency of
the wingless allele is 0.1. Wingless flies now survive normally.
- What are s and h for the non-sticky situation?
- What will be the allele frequencies and genotype frequencies in the adult
flies of the next generation?
- Sketch the likely long-term allele frequencies of this population cage.