The heterozygous genotype for sickle-cell anemia

The heterozygous genotype for sickle-cell anemia has little survival value for North American blacks because ( 1) the sickle-cell allele is being transmitted to the non-black population. 2) immunization programs have nearly eliminated this disease. 3) malaria is uncommon in North America 4) the frequency of the sickle-cell allele is declining. Question 10 0 / 1 point Use the following information to answer the next two questions Some small pools in Death Valley, California, are home to different species of pupfish. These fish have inhabited the pools since the lake that used to cover the area began to dry up about 10 000 years ago. Each pool contains a different species of pupfish that has evolved from the ancestral stock. This is likely due to 1) reproductive isolation and constant gene frequencies