The time has come when the explanations of evolution need to be, and can be, looked on in a light free from control by dogma. When this is done the hollowness and the hatefulness of the long reign of the much more than Darwinian Neo-Darwinism is clear as day.
Let us glance over the history of the doctrine.
The Greeks had ideas about evolution based less on known facts than on the visions and promptings of minds endowed with creative imagination. Yet these ideas foreshadowed in curiously close approximation the evolution conceptions, not only of the natural philosophers of the seventeenth and eighteenth centuries, to whom are usually ascribed the first formulations of the evolution doctrine, but even many of the newer formulations of the present and just passed centuries.
Even the essence of Darwin’s famous explanation of evolution by natural selection is suggested in the expressions of some of the Attic philosophers. As, for example, in the writings of Empedocles, who conceived of a creation of separate animal parts of a great variety of kinds and the coming together of some of these parts to form viable organisms and of others to form combinations unable to persist as successful creatures, because unfit to meet the demands of natural conditions.
But it was the great French naturalists, Buffon and Lamarck, who first expressed the evolution conception in fully worked out and reasonable form, while it was Lamarck who first offered a simple and wholly plausible explanation of evolutionary cause and control. His explanation remains to-day the simplest and most appealing to the reasoning mind of any that has been offered.
Unfortunately it lacked, and still lacks, the necessary basis of indispensable proof for its most fundamental assumption, to-wit, “the inheritance of acquired characters,” that is, the inheritance by the immediate offspring of those structural and functional changes or “acquirements” which came to the parents during their life because of their special use or disuse of parts and their individual reactions to environmental conditions. The young giraffe had a longer neck than it otherwise would have had because its parents had stretched their necks by continual reaching up to the leaves on the highest branches. The young man-thing of Glacial Times had weaker and less developed scalp muscles because its parents had gradually given up any considerable use of these muscles for twitching their heavy shocks of hair to frighten away the flies.
Then came Darwin with his natural selection explanation, a very different explanation from Lamarck’s, and one also very plausible and logical. Darwin did not altogether disbelieve in Lamarck’s theory; but he believed much more in his own. Later came the Neo-Darwinians, and they went the whole way of rejecting Lamarck’s explanation entirely, and accepting the natural selection explanation as the wholly sufficient cause and the only one needed to explain all evolution. The leader of the Neo-Darwinians was August Weismann of the University of Freiburg. He had as followers most of the German natural philosophers.
What is this “natural selection” that we all know so well by name, and so little, I am afraid, by content? For natural selection is much more widely known as a dominating scientific dogma, accepted popularly with little question as a sufficient explanation of evolution, than as something to be itself explained and viewed with a proper scientific doubt. As a matter of fact, it is high time that it should be generally known that not many naturalists of standing today accept natural selection as a sufficient explanation of the thoroughly accepted fact of evolution, or even as the most important among the numerous probable contributing factors of evolution. Indeed there are many reputable naturalists who repudiate natural selection altogether, as an actual contributing factor in species-forming and descent, and concede its influence as an evolutionary control, only in most general relations.
But in the popularization and wide acceptance of the natural selection dogma, we are in face of one of those familiar histories of the rise and dominance of a plausible, logically-constructed, apparently simple and sufficient explanation of a great problem pressing for solution. It is difficult for the world to accept the evolution theory without a causal explanation of it. But as the known facts prove the theory beyond reasonable doubt, it is necessary to accept it. Hence there is to most people a simultaneous necessity for accepting some explanation of it. Natural selection has had the fortune of being, since Darwin’s time, the generally accepted explanation. What then is it, really?