The Origin of Human Races and the Antiquity of Man Deduced from Natural Selection

Since populations increase in a geometric ratio while their actual numbers remain stable on average, it follows that as many die every year as are born. Therefore, if we deny natural selection, it can only be by asserting that—in the case I have described—the strong, healthy, swift, well-protected, and well-organized animals have no advantage over the weak, unhealthy, slow, poorly-protected, and imperfectly organized ones. To deny it is to say that the superior individuals do not, on average, live longer than the inferior ones; and no sane person has yet been found bold enough to assert that.

But this is not all; because offspring on average resemble their parents, the selected portion of each succeeding generation will be stronger, swifter, and more thickly furred than the last. If this process continues for thousands of generations, our animal will have once again become thoroughly adapted to the new conditions in which it is placed. However, it will now be a different creature. It will be not only swifter, stronger, and more furry; it will also probably have changed in color and form, perhaps having acquired a longer tail or differently shaped ears. It is an established fact that when one part of an animal is modified, other parts almost always change in sympathy with it. Mr. Darwin calls this “correlation of growth,” and gives as instances that hairless dogs have imperfect teeth; blue-eyed cats are deaf; small feet accompany short beaks in pigeons; and other equally interesting cases.

Grant, therefore, these premises:
1. That peculiarities of every kind are more or less hereditary.
2. That the offspring of every animal vary more or less in all parts of their organization.
3. That the universe in which these animals live is not absolutely unchanging.

None of these propositions can be denied. Consider then that the animals in any country (at least those which are not dying out) must, at each successive period, be brought into harmony with their surrounding conditions. We then have all the elements for a change of form and structure in animals that keeps exact pace with changes of whatever nature in the surrounding universe. Such changes must be slow, for the changes in the universe are very slow. But just as these slow changes become important when we look at results after long periods of action—as we do when we perceive the alterations of the Earth’s surface during geological epochs—so the parallel changes in animal form become more and more striking according to how much time has passed. We see this when we compare our living animals with those which we unearth from each successively older geological formation.

This is briefly the theory of “natural selection,” which explains the changes in the organic world as being parallel with, and in part dependent on, those in the inorganic world. What we now have to inquire is: Can this theory be applied in any way to the question of the origin of the races of man? Or is there anything in human nature that takes him out of the category of those organic existences over whose successive mutations it has had such powerful sway?

In order to answer these questions, we must consider why it is that “natural selection” acts so powerfully upon animals, and I shall, I...