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

...believe, find that its effect depends mainly upon their self-reliance and individual isolation. A slight injury or a temporary illness will often end in death because it leaves the individual powerless against its enemies. If a plant-eating animal is a little sick and has not fed well for a day or two, and the herd is then pursued by a beast of prey, our poor invalid inevitably falls victim. Similarly, in a meat-eating animal, the slightest lack of vigor prevents it from capturing food, and it soon dies of starvation. As a general rule, there is no mutual assistance between adults to help them survive a period of sickness. Neither is there any division of labor; each must fulfill all the conditions of its existence, and, therefore, "natural selection" keeps everyone up to a fairly uniform standard.

But in humans, as we now observe them, this is different. Humans are social and sympathetic. In even the most primitive tribes, the sick are assisted at least with food; having less than average health and vigor does not automatically result in death. Neither does the lack of perfect limbs or other organs produce the same effects as it does among animals. Some division of labor takes place: the fastest hunt, while those who are less active fish or gather fruits; food is, to some extent, exchanged or shared. The action of natural selection is therefore restrained; the weak, the small, those with less active limbs, or those with less sharp eyesight do not suffer the extreme penalty that falls upon animals with such defects.

As these physical characteristics become less important, mental and moral qualities will have an increasing influence on the well-being of the race. The capacity for acting together for protection and for obtaining food and shelter; sympathy, which leads everyone to help each other in turn; a sense of right, which prevents us from preying upon our peers; the decrease of aggressive and destructive tendencies; self-restraint regarding immediate desires; and that intelligent foresight which prepares for the future—these are all qualities that, from their earliest appearance, must have benefited every community. Therefore, they would have become the subjects of "natural selection." It is evident that such qualities would promote human well-being; they would protect people against external enemies, internal conflicts, and the effects of harsh seasons and looming famine more surely than any merely physical change could. Tribes in which such mental and moral qualities were dominant would, therefore, have an advantage in the struggle for existence over other tribes in which they were less developed. They would survive and maintain their numbers, while the others would decrease and finally perish.

Furthermore, when slow changes in physical geography or climate make it necessary for an animal to alter its diet, its natural covering, or its weapons, it can only do so through a corresponding change in its own body structure and internal organization. If a larger or more powerful beast must be captured and eaten—such as when a meat-eating animal that has previously preyed on sheep is forced by their decreasing numbers to attack buffaloes—only the strongest can survive. Only those with the most powerful claws and formidable canine teeth can struggle with and overcome such an animal. Natural...