The truth of this statement seems self-evident. Obviously, that which is better must result in better performance and better success in life. Obviously, if this process is carried on long enough, the preservation of better individuals will result in new breeding populations called species. Furthermore if the process continues for geologic ages, those new species will diverge into vastly differing families, classes, and phyla. The process of selection is self-contained, natural in a mechanical sort of way, and requiring no meddling from any intelligent designer. These are the fundamental claims of evolution of any stripe.
 
But let us pause a moment to reconsider the obviousness of Darwinian dogma in the face of an inconvenient fact: in any given species, a vast array of variations persist. This is odd. Why are there so many varieties of cattle, dogs, pigeons? Why so many variations of mosses, jellyfish, algae, and bears within a species? Why are offspring not exactly like their parents? Why do so many extremely unusual traits like dwarfism and albinism continue to be preserved in small quantities in populations? Why are populations not made up solely of the most successful, most reproductive, most robust traits all wrapped into one superior package?
 
I propose that the answer to these questions lies in the fact that there is no such thing as a clearly superior trait. It is not possible to state unequivocally that a certain trait endows an individual with 0.1% or 100% improvement in survivability. There are two main reasons: First, environments themselves vary substantially enough to promote differing traits. A trait which may offer clear superiority one day may be inferior the next. Second, it is so difficult to distinguish tiny degrees of superiority that chance effects predominate and many variations are preserved.
 
Many Small Variations are Necessary to Stable Populations
 
It takes no great insight to see how this works in everyday life. Athletic young men who perform well in high school obtain scholarships to colleges where they thrive as campus heroes and attract notice from coeds. Bookish nerds attract little female notice in high school and college but become very desirable when they lead billion dollar software companies. Both types are superior in one environment and inferior in another. Both types are necessary to a robust population of humans. But neither will come to predominate in a population. 
 
What's true for humans is also true for garden plants, fish, bacteria, or any other living thing. Even the narrowest environmental niche provides ample opportunity for different variants to thrive. The gray wolves of Alaska tend towards darker coats in the forested southern regions and towards lighter in the open snowy  plains of the north. Yet in either region there will be a few individuals of the opposite coat. Were all the northern population to be wiped out, the lighter coat advantageous to the snowy regions would still be preserved and would soon repopulate the north. The variation in coat color is essential to the robustness of the species.
 
The Difficulty of Distinguishing and Choosing Small Variations
 
There is yet another difficulty in the proposal that small improvements will be preserved, then predominate, and finally take over a population. That difficulty is in understanding how such a tiny improvement can even be recognized as an improvement. 
 
If a teacher were introduced to two very bright students and told that one of them was 0.1% more intelligent than the other, would not the teacher consider they were identical in intelligence? In fact might not the teacher question the testing procedure that claimed to produce such accuracy? After all an intelligence test would require a minimum of 1000 questions to have any claim to such accuracy. Surely factors other than intelligence would greatly influence the results of such a fatiguing test.
 
And would not the same doubt hold true for differences in athletic ability? How many races would have to be run to prove that one sprinter was, beyond the shadow of a doubt, 0.1% better than another? The answer is well over 10,000, which is a staggering number and well beyond the capabilities of any human. 
 
Furthermore, it is clear that the measurement of tiny differences in real performances will always involve many chance elements of a trivial nature. Perhaps a close race will be won because of shoes being laced more tightly. Or a golf match because of a favorable gust of wind. Or a weightlifting contest because of a slight improvement in the resonance of the barbell. 
 
Therefore, it seems highly unlikely that Nature could consistently and accurately make such refined distinctions.
 
Summary
 
So returning to Darwin's dogma, it is far from obvious that nature is constantly preserving slight improvements and eliminating slight defects. The balance point between the two is constantly shifting. Thus, what should have been obvious to Darwin is not that natural selection impels movement towards the creation of a new species but rather that natural selection preserves many variations so that the population as a whole will be robust and stable in differing environments.
 
In short, natural selection preserves what exists but does not create originality.
 
Laszlo Bencze


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