The graph below shows genotype percentages for generations 20 through 26. the initial genotype percentages were 34% dd, 32% dd, and 34% dd. the fitness levels were 100% for dd and dd; and 60% for dd. why does the deleterious dd genotype persist for so long in the simulation?

The graph below shows genotype percentages for generations 20 through 26. The initial genotype percentages were 34% DD, 32% Dd, and 34% dd. The fitness levels were 100% for DD and Dd; and 60% for dd. The reason why the deleterious dd genotype persists for so long in the simulation is…

C) Although dd parrots are much less likely to survive and reproduce, new dd parrots are constantly being born from Dd Dd pairs.

I hope it helps, Regards.

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."