Darwin’s natural selection is a theory where environmental factors play a larger role for each generation of a species that has started off with a plethora of heredital variation. By the time Darwinism was booming in the late 19th century, Mendel had further investigated these variations of heredity and had already gave solutions for Darwin on his idea on natural selection. As a result some of Mendel’s variations on heredity have refuted and/or supported the idea of natural selection. Darwin at the time had believed in blending inheritance which was a contradictory theory against natural selection which was a huge issue by the early 19th century. Some of Darwin’s contemporaries needed answers to this phenomenon. The problem with blending inheritance is that rare variants, such as black bunnies will have no opportunity to increase in rate of production even if they survive and reproduce more compared to white bunnies. The black bunnies will gradually disappear over time. By the mid 19th century, Mendel had found the solution to the issue, it is not traits that are transmitted by inheritance, instead it is genes that are transmitted.

References:

Mendel, Darwin, and Evolution. (n.d.) Retrieved April 12, 2017 from:

http://www.scientus.org/Mendel-Darwin.html