Not all members of a species are the same. every species exhibits ?
? like eye color, are passed from parent to offspring.

Not all members of a species are the same. Every species exhibits variations in different traits like eye color, that are passed from parent to offspring.

This statement is paraphrased from the Darwins's theory. Darwin's theory suggested that there are variations among individuals in a population and that these variations will help individuals to survive. Natural selection is the differences in survival and reproduction as the consequence of differences in phenotypes.