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Monday, July 26, 2010

The Scope of Evolution?

We evolutionists desperately want to quantify evolution. We are embarrassed by the continued lack of measurability and predictability one would expect from a true theory-based science. In the place of true metrics, we defer to the vague, broad, and situationally dependent term; "fitness".

We say that genetic variability in the population of any given lineage will insure that some individuals express traits that provide a survival advantage. Given the particularity of a given environment's mix of resources and challenges, not all individuals will have the genes necessary to make them fit. We say that there is always some small diversity in any population, a variability caused by sexual mixing, mutation, and a whole slew of non-genetic processes that indirectly effect either the actual genes inherited or conditions under which those genes are expressed. We say that this variability across a localized population is enough to influence who will survive and who won't, or most importantly, who's genes will be expressed in the next generation and who's won't. We assert that this process is obvious, observable, and predictable. And of course we are correct. We can and do produce laboratory experiments and field observations in that show that genes predict traits, genetic variability is correlated to population variability, and environmental conditions act as filters selecting towards individuals or populations expressing some genes and against those with others.

Well that all sounds good… model driven prediction, physical mechanistic explanation, solid techniques for observation… like a real science. If, that is, you are content to restrict your inquiry to the how.

If you are content with an understanding of evolution that is restricted to biology. If you are content with an understanding of evolution that blindly accepts as dependent factors, such temporal notions and shifting and immeasurable terms as "environment" and "fitness" and never ever asks, "Why?", then you probably won't need to read any further.

But if you, like me, would like to understand evolution in its largest context; independent of domain, and across all time, then you already know that evolution's current answers, though already correct and verifiable by any standard, is not yet a true science.

When Newton sought to define motion (and yes I know that Einstein perfected it through Relativity and quantum theory), he didn't do so only for an apple falling from a tree… but universally, for all physical bodies in all situations. His equations predict the position, speed and trajectory of an object into any distant future and across any distance. If the same could be said of evolution theory, we would have in our possession theory and or equations that we could use to predict the outcome of evolution across any span of time and in any domain.

Yet, of course we don't. We know all kinds of things about the interaction, within the domain of biology, of germ and progeny, of reproductive selection and mutation, of the relationship between genotype and phenotype, and of the competition over resources and of the crazy alliances and unintuitive and unplanned results of cooperative adaptation (including the tightly wound dance between predator and prey, between parasite and host).

But these processes, no matter how well understood, measured, researched, and modeled, are not what could be called the primitives of evolution. To be primitives, they would have to be universal. They are not universal. Thinking so would be like Newton thinking his laws only applied to cannon balls or things made of metal. So ingrained is the false correlation between biology and evolution that it is often impossible for me to get people to continue a discussion about evolution when I say "Let's talk about evolution in other systems." or "Let's talk about evolution as domain independent phenomenon."

If evolution isn't a "general" phenomenon, then someone representing the "special theory of evolution" will have to show how it is that life evolves but other systems do not. I doubt this requirement can be met. It would mean that some line can be drawn in time, before which there wasn't evolution, and after which there was. The logical inconsistency arises when one realizes that, to get to that line, some process suspiciously similar to evolution would have to have transpired to advance complexity to the level just preceding biology.

Another way to frame the overarching question of the why of evolution starts with the realization that competition within an environment isn't restricted to the various individuals of one species. Nature isn't that well refereed. In fact, nature isn't refereed at all. Nature is a free for all pitting snail against walrus against blue green algae. And it doesn't stop there. The ocean currents compete to transfer heat and in doing so, effect the food available to marine life of all kinds. In a very real sense, in an exactly real sense, a hurricane competes directly with a heron. Even the more stable artifacts of an environment, the topology and physical composition of the geographic features below foot compete actively and dynamically with the biota growing in its fissures and above its slowly moving face. Our old and narrowly-bounded definition of that which fits the category of evolution is plainly and absurdly and arbitrarily anthro-, species-, mammal, or bio- centric, and logically wrong.

Each time I introduce these new and inclusive definitions of the scope of the cast that performs in the play that is evolution, I hear grunts and groans, I hear the rustle of clothes, the uncomfortable shiftings… I hear frustration and discomfort. Hands raise anxiously with questions and protests: "How can non-living things evolve?" "Non-living things don't have genes, without genetics traits can't be transferred to or filtered from future generations!" And the inevitable, "The category containing all things is a useless category!"

I can't say that I don't understand, don't appreciate, or in some real way haven't anticipated and sympathized with these bio-centric apologies. This is how evolution has been framed since Erasmus Darwin and his grand kid Charles first seeded the meme. I will therefor take a moment to address these two dominant arguments such that they can be compared with a domain-independent definition of evolution.

First, lets look at evolution's apparent dependence upon genetics. How could evolution work if not for a stable medium (DNA) for the storage and processing of an absolute recipe for the reliable re-creation of individual entities? You may be surprised that my argument starts with an agreement; evolution is absolutely dependent upon the existence of a substrate stable enough to transfer existing structure into the future. But does that stable structure have to be biology's famous double helix? Absolutely not! In fact, it is causally impossible to find a system within this Universe (or any imaginary universe) in which the physical makeup of that system and its constituent parts does not facilitate the requisite structure to transfer conditions and specific arraignments from any present into any trailing futures. The shape of a river valley is a fundamental carrier of information about that valley into the future. The position, mass, and directional velocity of celestial bodies is sufficient carrier of structural information to substitute handedly for the functional duty that DNA performs in biology. But it is also important to realize and fully absorb the opposite proposition. DNA is not the only way that biological systems reliably transfer information about the present into the future. Biological systems are of course just as physical as galaxies, stars, and planets. The same causal parameters that restrict the outcome of any particular then (as a result of any particular now), that restrict causality to an almost impossibly narrow subset of what would be possible in a purely random shaking of the quantum dice. DNA is especially good at what it does, but it doesn't own or even define the category.

The second argument against an all-inclusive, domain independent definition of evolution – the logical argument against the usefulness of category that contains everything – well let's start by parsing it semantically and rhetorically. On face, there is no way to argue. The category "all" is a category of little worth. There is nothing to be known of something if it can't be compared to something else. But, and this should be obvious, I am not trying to create a category; quite the opposite! My intent is to create a theory of everything. Such a theory would obviously fail if it didn't apply to everything. So, semantically, this "set of everything is a useless set" argument doesn't map to the topic at hand. I get the distinct feeling that the argument is meant pedantically, and purposely, to derail and obfuscate the logical trail I am attempting to walk the audience down. It is a straw horse. It looks logical, but it doesn't apply.

A much more instructive and interesting line of questioning would go to the plausibility of a domain independent theory of evolution, what it would or would not change regarding our understanding of the emergence of complex structures (and their accelerating complexity), how it modifies our understanding of biological evolution, whether or not evolution will stand up to the requirements of a "theory of everything" (how it compares with others), and maybe even the effectiveness of my own description of this idea.

So, why is it important to me for evolution to meet the test of a "theory of everything"? First, I loath the unexplained. If evolution only talks to the mechanism of change within biology, then evolution would necessarily stand upon a stack even more foundational truths, and, as I mentioned earlier, other parallel theories would have to be developed to explain the emergence of complexity in non-biological systems. Either way, a vacuum would remain, exposing a need for the development of a foundational theory or set of theories that would support what in biology we call evolution, what in geology we call tectonics (etc.), what in meteorology we call heat dissipation cells, what in culture we call engineering, cooperative networks, etc.

What makes this whole endeavor so tricky, is that we tend to confuse mechanism with purpose. We get so caught up with the almost impossibly complex molecular mechanism (nucleic acids) by which biology builds complexity, that we forget to look at why it bothers at all. This why, this great big why, is to my mind far more fundamental and interesting and once understood, provides a scaffolding from which to comfortably understand and predict the necessary meta-components that need to be present in some form or another, in any evolving system. And, if you like elegance in a theory, it gets even better. It turns out that a byproduct of evolution as a theory of everything is that it must therefore be based on the two physical principals that have stood the test of universality – thermodynamics and information theory, and it strengthened both of these theories in the one area they were weak – dynamics. Once you understand the motivation and demands of change itself, the particular mechanisms of evolution at play in any one domain are reduced to how, are, no matter how varied, are but skins worn by a beast who's behavior becomes more and more predictable and universal.

All systems have what it takes to evolve. All systems are composed of components that in some small way differ. That difference might be in how the parts are made, or it might be in how the parts are distributed, and it most probably is both. That is all a system needs for the process of evolution to apply. So long as there is a difference somewhere in the system, or in that system's interaction in the greater environment in which it exists, evolution needs must be happening all of the time.

So just what is it that evolving things compete for? Is it food? Yes. Is it safety? Yes. Is it comfort? Yes. Is it stability? Yes, that too. For plants, competition is for solar radiation, carbon dioxide, water, a stable place to eat, grow, mate, and rase offspring. We animals need far more energy than our skin could absorb even if it was all capable of photosynthesis. So we eat things that can. And that is just the way things work. To get ahead, things learn to take advantage of other things. One might even say that the advantage always goes to those entities that can take the greatest advantage of the the productive behavior of the greatest number of other things. If you can't make enough energy, then eat a lot of things that can.

One could imagine taking this line of reasoning to the extremes. Lets define fitness as the ability to sit on the apex of a food chain. Of course you have to keep moving. If you don't stay vigilant and obsessive, always trying to find new and better ways to eat more of the other things, you will succumb to competition by things that do.

… to be continued …

Randall Reetz

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