Charles Darwin and Alfred Russel Wallace jointly presented their theory of natural selection in 1858.
The presentation took place at a meeting of the Linnean Society of London on 1 July 1858. It combined Wallace’s essay, written in the Malay Archipelago, with extracts from Darwin’s unpublished work and a letter Darwin had sent to the botanist Asa Gray.
Darwin had been developing the idea for roughly two decades, but Wallace’s essay—sent from Ternate after he independently reached a similar explanation for how species change—prompted Darwin and his supporters Charles Lyell and Joseph Hooker to arrange a joint presentation. Neither Darwin nor Wallace attended: Darwin was mourning the death of his infant son, Charles Waring, while Wallace remained overseas.
The papers were printed later that year under the lengthy title “On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection.” A common mix-up is to give 1859, the year Darwin published On the Origin of Species. The shared first announcement of the theory came in 1858.