The sickle cell allele is an example of which evolutionary force? how many base changes result in hemoglobin s? in which environment does possessing a sickle cell allele provide an advantage? what is the favored genotype?

The allele for sickle cell anemia would be an example of natural selection. In most situations, having crescent shaped red blood cells would hold less oxygen & would not be ideal. But in places that are affected by diseases like malaria, which attack red blood cells, having crescent blood cells minimizes the threat malaria can cause.

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The correct answer is: making up measurement to record