A year before the publication of his On the Origin of Species, Darwin co-authored with Alfred Russel Wallace the first publication detailing their view of natural selection. Wallace was the younger of the two and less well-known in the scientific circles of the time. Like Darwin, he was a veteran of serious exploration in remote (for Europeans) corners of the world, particularly South America and southeast Asia. Independently from Darwin, Wallace formulated essentially the same idea that variation and differential survival over many generations provided the mechanism by which biological diversity evolved. The letter Darwin received from Wallace in 1858 detailing this idea finally motivated him to act publicly. With the encouragement of his colleagues Joseph Hooker and Charles Lyell, Darwin jointly published a paper with Wallace in the Journal of the Proceedings of the Linnean Society, Zoology, entitled “On the tendency of species to form varieties; and on the perpetuation of varieties and species by natural means of selection.” On July 1, 1858, in the absence of both authors and a year before the Origin was published, this paper was read publicly at a meeting of the Linnean Society in London by George Busk, a secretary of the society.