Darwin's Origin of Species had an extraordinary influence, though not
at first on the experts of the science. It took zoologists and
botanists several years to recover from the astonishment into which
they had been thrown through the revolutionary idea of the work. But
its influence on the special sciences with which we zoologists and
botanists are concerned has increased from year to year; it has
introduced a most healthy fermentation in every branch of biology,
especially in comparative anatomy and ontogeny, and in zoological and
botanical classification. In this way it has brought about almost a
revolution in the prevailing views.

However, the point which chiefly concerns us here--the extension of
the theory to man--was not touched at all in Darwin's first work in
1859. It was believed for several years that he had no thought of
applying his principles to man, but that he shared the current idea of
man holding a special position in the universe. Not only ignorant
laymen (especially several theologians), but also a number of men of
science, said very naively that Darwinism in itself was not to be
opposed; that it was quite right to use it to explain the origin of
the various species of plants and animals, but that it was totally
inapplicable to man.

In the meantime, however, it seemed to a good many thoughtful people,
laymen as well as scientists, that this was wrong; that the descent of
man from some other animal species, and immediately from some ape-like
mammal, followed logically and necessarily from Darwin's reformed
theory of evolution. Many of the acuter opponents of the theory saw at
once the justice of this position, and, as this consequence was
intolerable, they wanted to get rid of the whole theory.