Evolution under the philosopher’s lens

shark adaptation

Evolution through natural selection is surely the best historical analysis to account for the immense biodiversity we see in the world today. Everyone’s talking about it these days, and extending the abstract principle behind evolution – a selective algorithm – to other problem domains as diverse as the spread of religious beliefs to the growth of neurons in the brain.

And yet, does it tell us everything, or at least the most important things, that we aught to know about the nature of these wonderful dynamic systems we call life? Let us for a moment reflect on the barebones essence of evolution, and return to this pertinent question with an answer.

Proto-life consisted of replicating molecular templates. They had a molecular structure that gradually grew into a complex form, by colliding with and binding molecular building materials from the environment. This growing molecular template, once it reached a certain form, continued to bind with materials from the environment, and made a copy of it. The copy in turn grew and made another copy, and so forth.

Except that, this copy producing process was not perfect. Due to the detailed mechanics of how a template “bound together” another template, minor imperfections in form occurred. Usually this occurred due to environmental forces physically acting on the “work-in-progress” copy.

This imperfect copying introduced an amazing new time-staggered process that we could simply call “selection for robustness” in nature. That is, some templates which were slightly different from the others due to the aforesaid “copy imperfections”, were destroyed less easily by environmental forces. They were more robust. Thus they stood a higher chance of growing to the stage where they would copy themselves. In other words, there was an asymmetric culling of this proliferation of self-copying molecular templates. The templates that weren’t destroyed by the environment carried with them the modified structure (i.e. the copy imperfections that made them more robust), which in turn was passed down the “copy” generations.

These tiny modifications that caused the template to “succeed better in the environment” aggregated over countless copy generations. A range of replicators emerged that had physical configurations that made them visibly “more robust” in the environment. What were originally growing, self-replicating molecular templates, gradually transformed themselves into “dynamic molecular machines”, through the influence of a multitude of destructive environmental forces. They were the first living organisms.

They continued to become more robust, and the rest is history…

Now, in spite of the many challenges and modifications that one could throw at evolution, I sincerely doubt it can ever be falsified as a historical analysis of the complexification of life. It has withstood many intriguing criticisms in the past. One rather fascinating “spanner” thrown into evolution was the idea that organisms themselves play a bigger role in their own evolution by altering the environment around them, such as a surface creature suddenly borrowing underground, and altering its environmental pressures. So what? Life still evolves, and growth, replication and natural selection still occur.

All right. Now having said all this, let us put evolution under the lens of philosophical scrutiny.

Is evolution through natural selection an ontological fact to which we can attribute the status of a natural law, or is it a “phenomenon” in nature like (say) the photoelectric effect, or is it at least a propensity in the environment like the propensity for there to be lightning on a cloudy day? Or, strictly speaking, is evolution through natural selection only a good historical analysis, good because it provides us a way to summarize a unmentionably vast collection of independent physical events that lead to today’s biodiversity, in common language terms?

Let us for a moment digress and consider another “good story” as a sort of “humorous parallel” to evolution.

“Computers are the vastly complex tools they are today, because their manufacture is bootstrapped. There were early computers, which were used to manufacture the CPUs of the next generation of computers. The use of the earlier generation of computers to make better CPUs, resulted in more powerful and versatile new computers. This is what we call manufacture by bootstrapping. Over countless generations of computer manufacture, it caused an exponential increase in the power and versatility of the machines. Thus bootstrapping is the force which drives the increase in the versatility and power of computing”.

Now my friends, this computer story is not a tautology. There is empirical “truth” in it; bootstrapped manufacture is a sort of “historical principle” in computer engineering that explains one particular aspect of the advancement in computing capacity. The point is though, just because it is true and has explanatory value in historical terms, it is not the only truth to be learned about how computers increased in capacity. In fact, it is not even the most fascinating or pragmatically useful truth about the development of computing. The deeper engineering truths lie in the physical configurations of the machines and their functional designs. For example, the fetch-execute cycle and the early hardware that facilitated it. If a primitive man were teleported suddenly into today’s world and told about the principle of bootstrapped manufacture, he would simply be unable to do much with it. It would be true, but it would what some call a “blunt weapon”.

So is this story of evolution through natural selection. History has proven it to be a blunt weapon. Science is still struggling desperately to engineer living creatures. And in spite of the various computer simulations that are touted as “hopeful”, there is no visible progress in engineering the simplest replicating, growing, evolving system.

What has more utility to us human beings: calling evolution – a top-down explanatory construct in our minds – a “law” in nature, or understanding the exact physical configuration of the template that can replicate, and the laws that govern its behavior? The magic it would seem is in the template and its mathematics, and not in the “historical law”, in spite of its educational utility.

The better science lies in investigating the actual physical configurations that enable the various behaviors of living systems, beginning with understanding molecular-level replicators. We have mapped the human genome, but we are only just beginning to understand the problem of ontogenesis – such as the protein-folding problem. We seem nowhere near understanding the fundamental problem of creating an artificial gene, or a replicating template that can evolve in an environment.

There is a deeper philosophical implication of this story. The actual propensity, the “magic” if you like, of any given system lies in its configuration. There are ground conditions for any observable phenomenon, and there is an emergence of new systemic properties (holistic properties if you like) – the phenomenon itself. Take electromagnetic radiation for example. There is a particular ground condition to be satisfied, say a primed L-C Circuit. There is an emergent phenomenon; the electromagnetic disturbance that detaches and travels.

I believe the evolution of life went through countless such “ground states” that had emergent phenomenon, causing “runaway” evolution paths. Beginning with the basic problem of the physical configuration (or form) for the simplest molecular structure that could evolve in the first place. We are told it might have been an “RNA type” structure. But we don’t know. Why can’t a replicating structure be an exceedingly simple one to begin with? Why can’t we engineer such a simplified replicator, and cause it to chain-react with the environment, like it supposedly happened so long ago? After all, the “law” of Darwinian evolution seems to be pretty generic.

The reason we are still groping in the dark is because this growing, replicating template is not so simple, and we haven’t understood the mechanics behind it. The proto-cell and the proto-gene probably grew together, and we have no good physical understanding of what makes it chain-react with the environment. The day we do have it, the mathematical models and laws that govern the behavior of those primordial physical structures will be the “real” laws of the story of life. [NB: there is some work being done to understand replication via hypercycles for example, which offers hope]

Let me conclude by saying that classical evolution is not a tautology: it has excellent explanatory value towards understanding the complexification of life. It is a good historical analysis of the “big picture”. Crackpots who think that life was created in 4004 BC via a bolt of lightning are clean wrong. However, evolution is not a universal law of nature that explains the presence of life in the first place, or even the mechanics of growth and reproduction. I only wish that when some of us speak about evolution, we remain honest to this hard fact.

PS: I have borrowed many ideas from countless distinguished men and women of science in presenting my above viewpoint, such as Richard Dawkins, Dan Dennett, J.B.S. Haldane, Lynn Margulis, … or even my own dad. I couldn’t possibly recall them all, but I owe them the supreme debt of being a student of their ideas at one time or another.

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One Response to Evolution under the philosopher’s lens

  1. A few people who had read this post and whom I got feedback from, said that perhaps I was attacking a “straw man”. The problem, they said, was that everyone knows that Evolution is a fairly high-level explanation for the complexification of life, and that any one particular adaptation has a complex multifactorial physical explanation that the algorithm of evolution alone cannot account for.

    Let me say this, I hope that is the case, because the first article in response this year’s Edge question was by Susan Blackmore, and this is an extract: “Evolution by means of natural selection (or indeed any kind of selection—natural or unnatural) provides the most beautiful, elegant explanation in all of science. This simple three-step algorithm explains, with one simple idea, why we live in a universe full of design. It explains not only why we are here but why trees, kittens, Urdu, the Bank of England, Chelsea football team, and the iPhone are here.”

    No I’m not signaling out Susan for criticism, She is merely echoing the zeitgeist of the scientific establishment, views of the philosophers of science in particular. According to them, Evolution explains everything, its the universal acid. I beg to differ, if the word “explanation” entails a scientific theory, then the presence of an iPhone is not explained by the algorithm of evolution, imho.

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