In the evolutionary adaptation sense, what is fitness?

a. the reproductive success of an individual
b. the ability of an individual to survive
c. the strength of an individual
d. the larger size of an individual

a

The answer is letter A.

In the evolutionary sense fitness refers to the measure of reproductive success of an individual or of organisms in general. Those organisms that leave the largest number of mature offspring are the fittest. Fitness can be achieved through survival or mortality selection, mating success or sexual selection, and family size or fecundity selection. Fitness is critical for a species’ survival and is a major adaptation that all organisms do through a long period of time.