Multiple Choice
In those parts of equatorial Africa where the malaria parasite is most common, the sickle-cell allele constitutes 20% of the β haemoglobin alleles in the human gene pool.
In the United States, the parasite that causes malaria is not present, but it is present in African-Americans whose ancestors were from equatorial Africa. What should be happening to the sickle-cell allele in the United States, and what should be happening to it in equatorial Africa?
A) stabilising selection; disruptive selection
B) disruptive selection; stabilising selection
C) directional selection; disruptive selection
D) directional selection; stabilising selection
Correct Answer:

Verified
Correct Answer:
Verified
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