lamb or a fawn, which is able to recognize and follow its dam immediately after birth, displays much more knowledge of the world than does a young dog, and vastly more than a new-born infant, which cannot even seek the breast; but the mental traits acquired subsequently by the lamb are small as compared to those acquired by the pup, and infinitely little as compared to those acquired by the infant. It is to be noted, however, that though the most intelligent animals are generally the most helpless at birth, yet their helplessness is not alwa}*s due entirely to Cessation of Selection, whereby, owing to the substitution of reason for instinct as a chief factor in survival, the instincts are lapsed; but that reversed selection must often have played some part in the elimination of instinct, for often the helplessness at birth of many of the more intelligent animals is an advantage to them, either owing to the situations in which they are born, or to the manner in which their parents procure food. For instance, the kind of intelligence displayed by a young chick or lamb would be distinctly unfavourable to the survival of young jackdaws, parrots, or puppies. Nevertheless the general truth, that as reason increases instinct decreases, manifestly holds.
It follows as a corollary from the above, and as a proof of it, that animals in which reason predominates, which have little knowledge of the world at birth, but acquire much knowledge subsequently, must, when removed from the ancestral environment, display in a
flies and other small insects without actually pecking at them. In doing this, its head could he seen to shake like a hand that is attempted to he held steady by a visible effort. This I observed and recorded when I did not understand its meaning. For it was not until after, that I found it to be the invariable habit of the turkey, when it sees a fly settled on any object, to steal on the unwary insect with slow and measured step until sufficiently near, when it*advances its head very slowly and steadily till within an inch or so of its prey, which is then seized by a sudden dart.' "—Romanes' Mental Evolution in Animals, pp. 161–4.
