Darwin Correspondence Project

The quantity of Darwin’s correspondence increased dramatically in 1868 due largely to his ever-widening research on human evolution and sexual selection.Darwin’s theory of sexual selection as applied to human descent led him to investigate aspects of the structure and behaviour of other animals more extensively, and to further this programme, he re-established links with specialists who had provided assistance. Considerable correspondence was generated by the long-awaited publication of Variation in animals and plants under domestication. Having been advertised by the publisher John Murray as early as 1865, the two-volume work appeared in January 1868.