In your textbook, the lower frequency of sickle-cell anemia among present day American blacks as compared to West African blacks is attributed to:
A) genetic drift.
B) gene flow.
C) new mutations.
D) none of the above

Question

Quizplus · Accepted Answer

Gene flow, or the movement of alleles between populations, is the most likely explanation for the lower frequency of sickle-cell anemia among present day American blacks as compared to West African blacks. This is because the African slaves brought to America were a small percentage of the total African population, and therefore their gene pool for sickle-cell anemia was not representative of the entire population. Over time, there has been continued gene flow from other ancestral populations, leading to a decrease in the frequency of the sickle-cell allele in the American black population. Genetic drift and new mutations are not as likely to cause this phenomenon.

In Your Textbook, the Lower Frequency of Sickle-Cell Anemia Among