On this date, the English ornithologist John Gould was born. His identification of Charles Darwin’s finches was pivotal in the development of the theory of evolution presented in The Origin of Species.
When Charles Darwin presented his mammal and bird specimens collected during the voyage of HMS Beagle to the Geological Society of London at their meeting on January 4, 1837, the bird specimens were given to Gould for identification. He set aside his paying work and at the next meeting on January 10 reported that birds from the Galápagos Islands which Darwin had thought were blackbirds, “gross-bills”, and finches were in fact “a series of ground Finches which are so peculiar” as to form “an entirely new group, containing 12 species.” This story made the newspapers.
In March, Darwin met Gould again, learning that his Galápagos “wren” was another species of finch and the mockingbirds he had labelled by island were separate species rather than just varieties, with relatives on the South American mainland. Subsequently Gould advised that the smaller southern Rhea specimen that had been rescued from a Christmas dinner was a separate species, which he named Rhea darwinii, whose territory overlapped with the northern Rheas.
Darwin had not bothered to label his finches by island, but others on the expedition had taken more care. He now sought specimens collected by Captain Robert FitzRoy and crewmen. From them he was able to establish that the species were unique to the islands, an important step on the development of his theory of evolution. Gould’s work on the birds was published as Part 3 of The Zoology of the Voyage of HMS Beagle, under the Command of Captain FitzRoy, during the Years 1832 to 1836, edited by Charles Darwin and published in five volumes between 1838 and 1842.
During his life, Gould produced 41 lavishly illustrated volumes on birds from all over the world, containing in all about 3,000 plates, all lithographed and hand-painted. Of these, his Birds of Australia was particularly significant (1840-69) as the first comprehensive record of the continent’s birds and mammals. With its plates of the birds were descriptions and notes on their distribution and adaptation to the environment.