Part 3

Fossils have been found showing several gradations or stages in development intermediate between man and his pre-human ancestor--evidences which, if they do not completely bridge the chasm, stand as ruined pillars, broken arches, isolated spans of the bridge over which man was many hundreds of thousands of years in crossing.

The first skull discovered (sixty years ago) of the Neanderthal men was so entirely different from other pre-historic skulls that one scientist declared it was a mal-formation; but other fossils were found later that proved the peculiarities to be racial characteristics. These men, who lived in Europe down to thirty thousand years ago, were squat, bent-kneed, thick-skulled, almost chinless, and with ridge-like projections over deep-set eyes. In skull development they were lower than any savage of today.

Older than the Neanderthal race, and lower in the human scale, were the Heidelberg men, said to have been the first really human beings of whom we have fossil evidences. Judging from the age of the fossil beds they existed from 100,000 to 200,000 years ago.

Thirty years ago were found some of the fossil remains of a creature in Java, some forty feet below the surface, that show characters intermediate between the gorilla and the Neanderthal man; “the lowest human cranium yet described, very nearly as much below the Neanderthal as this is below the normal European.” This creature was named Pithecanthropus Erectus (erect ape-man).

Lack of space prevents even a brief description of other and intermediate types of man, such as the man of Spy, of Naulette, of Predmost, etc.

As the more man develops (becomes specialized) the farther he is removed from the lower animals, so, in tracing his descent toward his origin we find him approaching them, apes included, in general characteristics, for we approach the point of divergence.

Evolution is a fact. There is no doubt of that in the minds of those who have investigated the subject without prejudice and with the acquisition of truth as the sole aim. One may dispute a fact, but he cannot deny it out of existence. Those who feel a sense of shame for their close proximity to their cousin, the monkey, are advised to increase that distance by carrying to higher development those traits considered peculiarly human: Reason, a sense of justice, of broader sympathy, and tolerance.

By his great discovery Darwin delivered the heaviest solar plexus blow to human vanity it ever received. For this he deserves, and receives, the eternal gratitude of every right-thinking man and woman.

How was evolution brought about? What are its laws, and how do they work?

NATURAL SELECTION

When the farmer or the stock-breeder selects his seeds or his animals for propagating purposes he has an eye to a great natural law, heredity. He knows that scrub animals and the seeds of degenerate plants will stamp their inferiority upon their descendants. He has learned that like produces like, therefore he selects such seeds and animals as will produce those best suited to his purposes. He is not only guided by his knowledge of a great law of Nature, but in the main he is following her method in preserving and improving the breed. This method of changing and improving plants and animals under domestication is called artificial selection.

Plants and animals in the natural state are capable of multiplying at so enormous a rate that there is an incessant struggle for existence going on among them. If it were not for this fierce struggle with one another and with their enemies and other environmental forces in which the vast majority die early, the world would be overstocked. There is hardly a species of animal of which a single pair would not choke out all other animal life in a few generations by filling the world with its descendants if all of the one species were permitted to reach old age. If a pair of elephants (one of the slowest-breeding species of animals) should bring forth only six young ones, and all should live to be one hundred years old, their descendants in 750 years would number nineteen million--a number so great that they would form a closely-packed herd occupying forty-one square miles. The codfish produces nine million eggs a year. If each egg should develop into a mature fish, half of them females, in ten years the sea would be a solid mass of codfish.

This tendency to increase at so tremendous a rate, and the fact that no two individuals are exactly alike, supply the material and the conditions for the great law of natural selection to operate. Each individual must of necessity compete so fiercely with other individuals of the same species, and of allied species, and with enemies, with climate and changing conditions that out of the struggling many only a few live to propagate. Those individuals that vary from the mass in the right direction live; the others die, leaving few descendants, or none.

Though like produces like there are no two individuals exactly alike. If all of the same species were alike there would be no opportunity for the law of natural selection to operate. Nothing but chance would determine in the struggle for existence which individuals would live to propagate their species and which would die without descendants. Nor would it matter, so far as the species is concerned. But individuals do differ in their traits in some degree--Wallace has shown that variation usually amounts from ten to twenty, sometimes twenty-five, per cent of the varying part--and this variation, even if small, often spells the difference between an early death with no descendants and a long life with a numerous progeny.

By the law of heredity the descendants are endowed in a greater or less degree with the same life-saving characteristics of their parents. Each generation being subjected to this weeding-out process, and only a few of the best fitted individuals being selected to preserve the species, we can easily see that, as the generations come and go, those essential, life-saving characters or traits are being developed to a greater and greater degree. And this means change, modification of species.

With horn or tooth or claw or hoof or sting or poison or odor, among all the wild creatures that swim or crawl or run or climb or fly, the struggle for life and food and mate goes on today just as it has gone on for millions of years. Other factors in the struggle are alertness, agility, cunningness, sharpness of vision and hearing and smell, protective color of covering, fleetness of foot and wing, the degree of heat, the amount of moisture and the food supply.

The traits that survive are of course those that are the most useful in a given environment. (By environment is meant surroundings, all outside influences, the not-me of each individual.) A change of environment, of the conditions of life, calls for a re-adjustment of the traits most vital to the individual in the new environment. In one environment one highly developed trait would be most useful while in another some other character or set of characters would be the saving factor, because a change of environment means a change of weather conditions, of the food supply and the means of getting it, of enemies, etc.

From the foregoing brief outline it would seem that only a little exercise of reason is required of any one to see that natural selection operating in unlike environments would, in the course of many generations, produce from the same species types of animals (or plants) very unlike--not only unlike each other but unlike their parent species. At first these types derived from a common ancestor would be only varieties, but varieties are incipient species. Given sufficient time, and the intervention of natural barriers to prevent the crossing of extremes, and the creation of new species would be the natural result.

As a vivid illustration of how the law of natural selection works, and of how great is the sum of the results of its operation accumulated through many generations, let us observe one of many modifications an animal undergoes in its struggle for existence. To the question, “Why are animals of the arctic regions white?” we ought to be able, with what we already know of natural selection, to give the answer. Imagine those lands of snow and ice originally inhabited by animals of all colors from white to black, or even of all shades of one color, brown. The animals of what colors or shades, among the flesh-eaters, would have the least difficulty in stealthily approaching their prey, and so, be most apt to survive in the struggle against starvation? And which among the animals preyed on would run the least risk of detection and so be most likely to escape destruction? The answer to both questions, of course, would be, “Those whose colors most nearly conformed to the snowy background.” Imagine this process of culling out the darker colors continuing for many generations and we can understand that the whiteness of all arctic animals would be the inevitable result. We can also see why most wild animals of our regions are of colors that best harmonize with the brown earth and dead leaves. Let us keep in mind the fact that while we were observing the modification of one character, all the favorable variations, however slight, in every other character that could be of the least advantage to those creatures were being added up as fast as they appeared. After several generations, if for any cause the environment were undergoing a radical change, or if a species had migrated from a widely different one, a greatly modified animal would be the result. However, there can be no modification in an animal perfectly adapted to its environment--provided the environment does not change.

Every organ, and every other part of the body, internal and external, of every creature in the natural state is subject to modification by the law of natural selection, just as was the color of the hair or the feathers of polar animals.

Man’s method of improving plants and animals--artificial selection--interferes with the work of natural selection. For one thing, man makes a radical change in the environment of every plant and animal he domesticates; for another, man selects for other purposes than the one Nature has in view--that is, if it can be said that Nature has a purpose.

From the same parent stock man breeds one strain of cattle for beef, another for milk and butter; one variety of the horse for the saddle and another for draft purposes. Nature adapts the species to the environment--never the environment to the species--sacrificing those individuals that do not measure up to her standard. She seems to care only for the species, not for the individuals, or only for those individuals that give promise of a better species.

This secret wrung from Nature (natural selection as a factor in progressive development) is man’s most precious truth, for it is the key to his further progress.

To summarize: organisms tend to increase at a great rate; this intensifies the struggle for existence; organisms vary; in the struggle for existence the vast majority die early, leaving those that vary in the favorable direction to live and reproduce; this means change, progress. This is natural selection.

There is also De Vries’ “Mutations theory” which some scientists believe to have been an important factor in evolution. It is the theory that at times a species may progress by “jumps”--that is, that occasionally individuals come into existence that vary extremely from the mass, and that they may become the parents of a new species. It is on account of the relative value attached by some scientists to this theory and to natural selection that they disagree, and not in regard to whether or not evolution is a fact.

NATURAL SELECTION IN SOCIAL EVOLUTION

The law of natural selection, or of the survival of the fittest, is not confined to plant and animal life. Its sway is universal. Every thing that is born, spawned, hatched, sprouted, conceived, invented, or founded is tested by this law, and if found inefficient, unfit, is weeded out, leaving the fittest, the best, the truest to survive.

On the mental plane the law of the survival of the fittest is often restricted in its operation, and the struggle unnecessarily prolonged, because of the intolerance of those of the older, dominant belief. The world lags because they refuse to permit the new idea to meet the old on equal terms before the only court having jurisdiction over truth and error--the court of Reason.