The modern theory of genetics: An engaging description of Mendel and his work can be found in Mawer 2006.

A simple example will help to clarify: The description here is largely a simplified version of the explanation in Ridley 2004a, pp. 35–39.

it needed Mendelian heredity: First explained in detail in Fisher 1930.

In his autobiography, he acknowledged: Darwin 1958 [1892], p. 18. A more detailed analysis of Darwin’s numerical attempts can be found in Parshall 1982.

“I was blind and thought that single”: Letter to Wallace on February 2, 1869, in Marchant 1916, vol. 1. Also in Darwin 1887, vol. 2, p. 288.