Using a variety of experimental animals, Ferrier demonstrated that various neurologic functions were controlled by separate parts of the cerebrum and that damage or loss of that part created an irrevocable and particular deficit. He showed that these areas were much more discrete as one ascended the phylogenetic scale and that, accordingly, effects of brain damage in rabbits, dogs and cats etc. could not be compared to those in monkeys, apes and human beings. Clarke & O’Malley, The Human Brain and Spinal Cord, pp. 513-14. This paper became the basis of Ferrier's book, The Functions of the Brain (1876).