Everybody knows how natural selection works. And it does work, it has been observed in nature and we have manipulated it in the laboratory and even on the farm to develop new varieties of plants and animals. But lets review it for a moment, using an over-simplified example.

Suppose there is a small mammal that lives in a temperate climate, say a rabbit or weasel. It has brown fur which is good camouflage for its environment. Over thousands of generations, the fur has evolved (through natural selection) to be just the right color to allow it to survive in its range. Let us further assume that only one gene controls the fur color; in reality several, or even many genes interact to do this and many of these genes link to other characteristics, but for purposes of argument lets assume there is only one gene involved.

Suddenly, in the critter’s habitat, the climate starts to change, and it is gradually getting colder. The snow season becomes longer, from a few months a year to conditions approaching the Arctic. Over a period of several thousand years, the snow cover extends from just a short winter, to almost all year long, its a veritable ice age! The creature evolves to meet these new conditions, its behavior, metabolism, its entire biology is transformed to deal with its new habitat.
But let us ignore that for the moment, lets just focus on its fur. Its fur becomes white, to camouflage it from predators. And how this happens is easily explained by natural selection.

The organism has a white fur gene in its DNA, one inherited from its distant past since DNA generates random mutations and doesn’t throw anything away, and occasionally one is born with white, or whiter, fur. In normal times, the animal is an easy target for predators, but in this new snowy environment, the white pelt is a decided advantage. Those individuals born with white fur are more likely to survive, and they pass that trait on to their offspring. Through sex, the new gene is quickly spread through the entire population. Pretty soon, almost all of them are white, and the brown fur gene is locked away in the DNA in case the climate ever warms up again and its needed. That is the official version.

But we know its not that simple. For one thing, as we alluded to earlier, rarely are things like fur color simply coded on one single gene. The trait is shared by many genes, and it is often linked to other characteristics. So for the animal to change, many different genes have to be selected for, and not all of them are necessarily useful for a snowy climate. In fact, the white fur will be competing with other characteristics that may not be suitable for a colder habitat.

There is another factor as well, the animal just doesn’t need white fur, the new climate will require other characteristics, perhaps thousands of them. For example, if our beast needs a thicker layer of fat to keep it warm in the cold, and to store fuel, natural selection will have to provide that like it did the white fur. But those characteristics may not be linked. An individual with good insulating fat may not have white fur, and it will be picked off by predators, and vice versa: a perfectly camouflaged animal may freeze to death because he can’t keep warm and store nutrients. BOTH those characteristics will have to be selected for together, not just one or the other. And as we mentioned before, there aren’t just two competing characteristics required by the organism to adapt. There may be thousands of them that will be needed to deal with this climate change, their selection processes will be competing with one another, getting in each other’s way. Evolutionary theory explains nicely how one trait is selected for statistically, but fails utterly when thousands of traits, each going all the way down to the molecular level, have to be selected for simultaneously.

And one other thing. Even a single simple trait, like fur color, cannot be just one switch in the DNA. There must be many different mechanisms involved; genetic, physiological, biochemical, hormonal, embryological, that have to be coordinated and implemented in sequence to accomplish this simple change in hair color.

For animals with large populations, like microbes or insects, there is a huge statistical space where this selection of multiple traits can take place. But mammal populations, particularly in smaller habitats, simply don’t have enough members, and don’t have offspring in large enough numbers, or frequently enough, to provide a sufficiently robust statistical space for all the selection to happen. For example, whales (and early man) never had large populations. At most a few million of each species roamed the planet at any one time, and they may have been spread out pretty thin. This isn’t really a big enough and self-accessible and connected gene pool for creatures that have only one offspring per year, and the offspring requires several years to become sexually mature.

Natural selection works, there is no doubt about that. But there must be some other mechanism at work here, something Darwin missed. And I simply cannot accept supernatural or religious explanations for organic diversity and adaptation.

I suspect that DNA is not just a data storage medium, preserving the blueprints for protein synthesis and the schedules for their assembly into cells, tissues, organs, and organ systems. I believe DNA processes data, that it has some form of decision making capacity, that it can survey and evaluate the projected needs of the life form and react to them by designing alternative structures and behaviors to meet those needs. Its not just a memory, its a computer.

And yes, its not Lamarckian selection; I realize giraffes didn’t evolve longer necks by stretching to reach the leaves in upper branches. Its more subtle than that.

I’m not implying DNA is capable of conscious thought and reason, but that it is capable of somehow analyzing the genetic environment that it detects in the outside world through sexual contact and can (to a certain extent) reconfigure itself in response, thereby maximizing its chances of producing a successful adaptation to external conditions. It figures out which adaptations are likely to work for the organism, and then goes about coordinating and implementing them. I don’t believe it can be a purely random process; at least, not in higher life forms.

That’s a mouthful. Does anyone have any comments? Or should we just move this thread over to “Mysteries of the Multiverse”?