On the Origin of Species in its 6th edition, earning Darwin nearly £3000.) On 5 April, Darwin sent Murray the first three chapters, and a proposal for the book's title. An early draft title page suggests "On the Mutability of Species". Murray cautiously asked Whitwell Elwin to review the chapters. At Lyell's suggestion, Elwin recommended that, rather than "put forth the theory without the evidence", the book should focus on observations upon pigeons, briefly stating how these illustrated Darwin's general principles and preparing the way for the larger work expected shortly: "Every body is interested in pigeons." Darwin responded that this was impractical: he had
On the Origin of Species disperse across oceans to colonise distant islands. By 1856, his theory was much more sophisticated, with a mass of supporting evidence. In his autobiography, Darwin said he had "gained much by my delay in publishing from about 1839, when the theory was clearly conceived, to 1859; and I lost nothing by it". On the first page of his 1859 book he noted that, having begun work on the topic in 1837, he had drawn up "some short notes" after five years, had enlarged these into a sketch in 1844, and "from that period to the present day I have steadily