Sociology and Modern Social Problems | Page 9

of all
animal species.
It is evident that if we assume Darwin's theory of descent in sociology
we must look for the beginnings of many peculiarly human things in
the animal world below man. Human institutions, according to this
theory, could not be supposed to have an independent origin, or human
society in any of its forms to be a fact by itself, but rather all human
things are connected with the whole world of animal life below man.
Thus if we are, according to this theory, to look for the origin of the
family, we should have to turn first of all to the habits of animals
nearest man. This is only one of the many bearings which Darwin's
theory has upon the study of social problems; but it is evident even
from this that it revolutionizes sociology. So long as it was possible to

look upon human society as a distinct creation, as something isolated,
by itself in nature, it was possible to hold to intellectualistic views of
the origin of human institutions.
But some one may ask: Why should the sociologist accept Darwin's
theory? What proofs does it rest upon? What warrant has a student of
sociology for accepting a doctrine of such far-reaching consequences?
The reply is, that biologists, generally, during the last fifty years, after a
careful study of Darwin's arguments and after a careful examination of
all other evidence, have come substantially to agree with him. There is
no great biologist now living who does not accept the essentials of the
doctrine of descent. Five lines of proof may be offered in support of
Darwin's theories, and it may be well for us, as students of sociology,
briefly to review these.
(1) The homologies or similarities of structure of different animals.
There are very striking similarities of structure between all the higher
animals. Between the ape and man, for example, there are over one
hundred and fifty such anatomical homologies; that is, in the ape we
find bone for bone, and muscle for muscle, corresponding to the
structure of the human body. Even an animal so remotely related to
man as the cat has many more resemblances to man in anatomical
structure than dissimilarities. Now, the meaning of these anatomical
homologies, biologists say, is that these animals are genetically related,
that is, they had a common ancestry at some remote period in the past.
(2) The presence of vestigial organs in the higher animals supplies
another argument for the belief in common descent. In man, for
example, there exist over one hundred of these vestigial or rudimentary
organs, as the vermiform appendix, the pineal gland, and the like.
Many of these vestigal organs, which are now functionless in man,
perform functions in lower animals, and this is held to show that at
some remote period in the past they also functioned in man's ancestors.
(3) The facts of embryology seem to point to the descent of the higher
types of animals from the lower types. The embryo or fetus in its
development seems to recapitulate the various stages through which the
species has passed. Thus the human embryo at one stage of its

development resembles the fish; at another stage, the embryo of a dog;
and for a long time it is impossible to distinguish between the human
embryo and that of one of the larger apes. These embryological facts,
biologists say, indicate genetic relation between the various animal
forms which the embryo in its different stages simulates.
(4) The fossil remains of extinct species of animals are found in the
earth's crust which are evidently ancestors of existing species. Until the
doctrine of descent was accepted there was no way of explaining the
presence of these fossil remains of extinct animals in the earth's crust. It
was supposed by some that the earth had passed through a series of
cataclysms in which all forms of life upon the earth had been many
times destroyed and many times re-created. It is now demonstrated,
however, that these fossils are related to existing species, and
sometimes it is possible to trace back the evolution of existing forms to
very primitive forms in this way. For example, it is possible to trace the
horse, which is now an animal with a single hoof, walking on a single
toe, back to an animal that walked upon four toes and had four hoofs
and was not much larger than a fox. It is not so generally known that it
is also possible to trace man back through fossil human remains that
have been discovered in the earth's crust to the time when he is
apparently just emerging from some apelike form. The latest discovery
of the fossil remains of man made by Dr. Dubois in Java in 1894 shows
a creature