7. Sickle Cell Trait and Malaria
An extraordinary case of evolutionary trade-off is seen in the prevalence of the sickle cell gene in regions plagued by malaria. Individuals carrying one copy of this gene are less likely to develop severe malaria, granting them a survival advantage in these environments.
However, inheriting two copies leads to sickle cell disease, which poses its own health challenges. This delicate balance shows how evolution sometimes favors traits that come with significant risks, as long as they provide an overall advantage against environmental threats. CDC resource