Question

Which statement about fitness and natural selection is true?

a. Changes in the absolute numbers of offspring necessarily lead to changes in allele frequencies from one generation to the next.
b. Natural selection operates directly on the genotype.
c. The fitness of an individual is determined solely by its ability to survive.
d. The fitness of individuals of a particular phenotype is a function of the probability that such individuals survive, divided by the average number of offspring they produce.
e. The fitness of individuals of a particular phenotype is a function of the probability that such individuals survive, multiplied by the average number of offspring they produce.

Answer 1

The correct statement is that the fitness of individuals of a particular phenotype is determined by their survival probability multiplied by their reproductive output. Fitness involves both survival and the ability to reproduce, which directly influences the gene pool through natural selection.

Step-by-step explanation:

The statement about fitness and natural selection that is true is:

e. The fitness of individuals of a particular phenotype is a function of the probability that such individuals survive, multiplied by the average number of offspring they produce.

Fitness in the context of evolutionary biology describes how good a particular genotype is at leaving offspring in the next generation relative to how good other genotypes are at it. This definition encapsulates the ability to not only survive but also to reproduce. Natural selection, therefore, does not operate directly on the genotype only but rather on the whole organism, affecting its overall survival and reproductive success, which in turn influences allele frequencies within the population's gene pool.