Heredity and evolution relationship?

Intimate: "Survival of the fittest" means only 1 thing: you leave more progeny than peers. That is the only way to enable your genes to survive. In West Africa, with no medications for malaria prior to a blink of the eye in evolutionary time, sickle cell carriers were by far more likely to survive deadly falciparum malaria infection--whereas their normal hemoglobin brethren were more likely to die.