which they sleep; and as both species follow the same habit, it might be
argued that this was due to instinct, but we cannot feel sure that it is
not the result of both animals having similar wants and possessing
similar powers of reasoning. These apes, as we may assume, avoid the
many poisonous fruits of the tropics, and man has no such knowledge; but
as our domestic animals, when taken to foreign lands, and when first
turned out in the spring, often eat poisonous herbs, which they
afterward 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, has shown 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 among 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.[58]

But although, as we learn from the above-mentioned insects and the
beaver, a high degree of intelligence is certainly compatible with
complex instincts, and although actions, at first learned voluntarily,