lands, and when first turned out in the spring, often eat poisonous
herbs, which they afterwards avoid, we cannot feel sure that the apes
do not learn from their own experience or from that of their parents
what fruits to select. It is, however, certain, as we shall presently
see, that apes have an instinctive dread of serpents, and probably of
other dangerous animals.
The fewness and the comparative simplicity of the instincts in the
higher animals are remarkable in contrast with those of the lower
animals. Cuvier maintained that instinct and intelligence stand in an
inverse ratio to each other; and some have thought that the
intellectual faculties of the higher animals have been gradually
developed from their instincts. But Pouchet, in an interesting essay
(2. L Instinct chez les Insectes, Revue des Deux Mondes, Feb. 1870,
p. 690.), has shewn that no such inverse ratio really exists. Those
insects which possess the most wonderful instincts are certainly the
most intelligent. In the vertebrate series, the least intelligent
members, namely fishes and amphibians, do not possess complex
instincts; and amongst mammals the animal most remarkable for its
instincts, namely the beaver, is highly intelligent, as will be
admitted by every one who has read Mr. Morgan s excellent work. (3.
The American Beaver and His Works, 1868.)
Although the first dawnings of intelligence, according to Mr. Herbert
Spencer (4. The Principles of Psychology, 2nd edit., 1870, pp.
418-443.), have been developed through the multiplication and
co-ordination of reflex actions, and although many of the simpler
instincts graduate into reflex actions, and can hardly be distinguished
from them, as in the case of young animals sucking, yet the more
complex instincts seem to have originated independently of
intelligence. I am, however, very far from wishing to deny that
instinctive actions may lose their fixed and untaught character, and be
replaced by others performed by the aid of the free will. On the other
hand, some intelligent actions, after being performed during several
generations, become converted into instincts and are inherited, as when
birds on oceanic islands learn to avoid man. These actions may then be
said to be degraded in character, for they are no longer performed
through reason or from experience. But the greater number of the more
complex instincts appear to have been gained in a wholly different
manner, through the natural selection of variations of simpler
78