Population Genetics
Problems
Problem : In a given plant population, the gene that determines height has two alleles, H and h. In one generation, H has a frequency of p=0.8 and h has a frequency of q=0.2. in the next generation, p=0.7 and q=0.3. Is this population in Hardy- Weinberg equilibrium? Why or why not?
Problem : In a population of giraffes, the gene that determines neck length has two alleles, N for longer necks and n for shorter necks. Only giraffes with two N alleles will have long necks. In one generation, the frequency of N is p=0.4 and the frequency of n is q=0.6. This generation experiences a large forest fire that kills all low-growing plants, leaving tall trees with high branches as the only food source. In the next generation, 49% of giraffes have long necks. How much has selection contributed to the allele frequencies in the second generation?
Problem : In a population of giraffes, the gene that determines spot size has two alleles, S for larger spots and s for smaller spots. Giraffes with one of each allele have medium-sized spots. In one generation, the frequency of S is p=0.4 and the frequency of s is q=0.6. Since spots help the giraffes blend in with their surroundings, they are acted upon by natural selection. In the next generation, 64% of giraffes have small spots. What percentage of giraffes in the second generation will have medium spots? Large spots?
