Ornithologist and taxidermist. He was the first curator and preserver at the musuem of the Zoological Society of London in 1827. He published 41 beautifully illustrated folios on birds of all continents. He identified the species of birds now referred to as "Darwin's finches", which was instrumental to the inception of Darwin's theory of evolution by natural selection. His work on the birds was published between 1838 and 1842 as "Zoology of the Voyage of H.M.S. Beagle", edited by Charles Darwin. He travelled widely in Australia in 1838-1840 and was elected to the Royal Society, in 1843. His collection of mammels are now in the Natural History Museum.