Chapter 8. Evolutionary Epiphanies


In spite of my dislike of the modern neo-Darwinian theory of evolution, I was still captivated by the relationships, obviously the products of evolution, among organisms. I loved taxonomy, the identification of plants, and also systematics, the attempt to understand the evolutionary relationships of species past and present. It was the idea of natural selection as the driving force behind life forms and their evolution that seemed nonsensical and left me cold, even though that was politically unwise. When it comes to religion, I just can't suspend my disbelief, and I never could suspend it for neo-Darwinian theory, either.

Some years later, in an email discussion they were having (presumably with a physicist, but "geneticist" or "molecular biologist" could be just as easily inserted here), Jack and Cy pointed out a very basic flaw in the standard evolutionary dogma, giving clearer expression to my annoyance with this "theory:"

"One problem with physicists attempting to explain life is they take Darwin too seriously. The Darwinian world is a Newtonian world of pulls and pushes; what happens to an organism is determined by how the environment 'pulls' and 'pushes' on an organism. We suspect that physicists who write about life are aware of the inadequacy of the Darwinian world, but, for some reason, cannot see a viable alternative. We believe the source of that conceptual blindness rests with the belief that groups of organisms, populations or species for example, and not individual organisms, are the relevant biological items. If the individual is emphasized then development becomes the most relevant phenomenon in biology, and with that realization new ways of looking at organisms are obvious. When assemblages of organisms are stressed then development disappears into some vague black hole and any unifying processes or principles become lost."

On the other hand, I'll say it again - when physicists stick to their own areas of expertise, they seem to have an easier time of questioning their old theories and assumptions. They still honor Newton and teach his ideas in first year physics because they are good, workable approximations. But in terms of underlying theories of causality they have moved on - to relativity, to quantum physics, to string theory or some other unifying concept - and on they go, changing their minds and arguing with each other. Meanwhile, the poor biologists seem to prefer to handcuff and blindfold themselves. They still mostly avoid speaking the dreaded name "Lamarck," even though his ideas about evolution predated Darwin's by about 50 years, and some of his conjectures may turn out to not be so crazy after all. Darwin's writings are now around 150 years old, but biologists seem unable to give him the honor he is due and move on from there - they cling to him tenaciously, almost desperately. Why? I have never understood this. Surely there had to be viable alternatives to this magical idea of natural selection. Other ideas had to be out there and I wondered why biologists were so afraid to talk about them, why deviations from the standard dogma were considered heresy.

Grammatical Man, a book by a wonderful writer named Jeremy Campbell (1982. Touchstone Books, Simon & Schuster, Inc. N.Y) was making its way through some of the faculty and students at UBC in the mid-1980s. This non-technical book was a series of little stories about scientists, mathematicians and others who made early and more recent contributions to theories about information, self-organization, complexity and chaos. It was a delightful and inspiring book, even if it faded at the end. Perhaps it was too good, as it went out of print not very many years later. Among other interesting contributors, Campbell wrote about the chemist Ilya Prigogine who won a Nobel Prize in the late 1970s for suggesting an expanded role for, and a different way of looking at, the Second Law of Thermodynamics. I remember sitting on a Vancouver city bus, probably headed back to the dark little basement room I was renting. I was reading Campbell's discussion of Prigogine's ideas, which included a closing comment from the linguist and political activist, Noam Chomsky (pp. 101-102):

"The creation of structure depends on how far the system is from equilibrium, and this in turn depends on the rate and amount of exchanges of matter and energy with the surroundings. The distance from equilibrium will be great if there are many exchanges, and very small or nonexistent if there are few. The same laws of physics apply in both cases, but near equilibrium Prigogine says the laws lead to 'doom or destruction,' whereas further from equilibrium they may become processes of construction and organization. In this latter case, he adds, probability theory breaks down. Nonequilibrium can therefore be a source of order in open systems, whether these systems are chemical or biological, revealing a fundamental kinship between life and nonlife. Complexity is maintained in both types...Complexity is not just a matter of a system having a lot of parts which are related to each other in nonsimple ways. Instead, it turns out to be a property in its own right, and it makes complex systems different in kind from simple ones, enabling them to do things and be things we might not have expected. Chomsky suggests that human language competence, which must be among the most complicated structures in the universe, arises uniquely in evolution at a certain stage of biological complexity... Chomsky goes on to say, 'This poses a problem for the biologist, since if true, it is an example of true 'emergence' - the appearance of a qualitatively different phenomenon at a specific stage of organization.'"

The classical version of the Second Law of Thermodynamics says that if all of the oxygen, nitrogen and other molecules are held in one corner of a room, and then released, the molecules will spontaneously disperse from the area of high concentration to where molecules are few. They will drift about until they are more or less equally mixed throughout the room, moving to a patternless state of equilibrium. The cause of this spontaneous behavior is the Second Law, and the molecules diffuse throughout the room toward a random state of mixing because they must. Molecules at equilibrium move at random and the behavior of each is independent of the others.

Prigogine pointed out events beyond the classical understanding of the action of the Second Law, and argued that what occurs depends on the initial conditions. If energy is added to the room, say in the form of heat, the molecules move more quickly as they warm up, but then something unexpected happens. The behavior of the molecules becomes less random. The molecules form a larger, self-organized pattern, moving upwards, outwards and downwards in circular convection currents. There is no way to describe the convection current exclusively in terms of the atomic or molecular structures of nitrogen and oxygen because a different level of organization, an emergent structure, has been generated. The behavior does not arise from the molecules themselves, but from the relationship between the molecules and the energy introduced into the system. Prigogine argued that self-organization (that is, emergence) is a common phenomenon in many chemical systems under certain conditions where energy flows through and is captured by the system.

I couldn't pretend to understand it all, but to me, the most important discussion in Grammatical Man was about Prigogine's work on the expansion of the Second Law because it gives us an ultimate driving force, an explicit causality to include as a law in the explanans of the Covering Law Model. My interpretation of Prigogine's central points may be wrong, but I (and others) think he offered the primary missing piece at the core of self-organized, evolving, biological systems. Self-organization, that is, some sort of non-random pattern, forms spontaneously when energy flows through a system (or is captured by it, as is the case with functioning, living things). Given only the original version of the Second Law, the self-organization of anything would seem to absolutely defy it. Ludwig Boltzmann's earlier version of the law, the version we learned about in introductory chemistry, says that all things spontaneously go to equal mixing, to equilibrium, to maximum entropy - a one-way move to randomness. That isn't always quite right, said Prigogine; when there is a flow of energy into a system, it changes, it expresses pattern, and entropy is now dissipated in a different way. Entropy is expressed as randomness in a system that is closed to the flow of energy, but in a self-organized system open to energy, such as a living creature, entropy may instead be manifested as novelty, as surprise, as something unpredictable, even astonishing. In these events caused by the Second Law, I think the idea of non-determinism partially applies - the components of a system at equilibrium are random and patternless, predictable in a probabalistic sort of way, but there's no telling where a given molecule might be at any particular moment. However, many aspects of self-organized systems are predictable because they are constrained both by characteristics of their evolutionary history, and by the demands of being a functional organism. These systems are orderly, but they are always accompanied by something surprising. The "surprises" in nature tie into ideas about chaos and information, and also about order, as Campbell points out in a beautiful and thrilling passage at the beginning of Grammatical Man:

"The proper metaphor for the life process may not be a pair of rolling dice or a spinning roulette wheel, but the sentences of a language, conveying information that is partly predictable and partly unpredictable. These sentences are generated by rules which make much out of little, producing a boundless wealth of meaning from a finite store of words; they enable language to be familiar yet surprising, constrained yet unpredictable within its constraints...The world need not regress toward the simple, the uniform and the banal, but may advance in the direction of richer and more complex structures, physical and mental. Life, like language, remains 'grammatical.' The classical view of entropy implied that structure is the exception and confusion the rule. The theory of information suggests instead that order is entirely natural: grammatical man inhabits a grammatical universe."

This expanded version of the Second Law describes the general behavior of many phenomena. Order can be spontaneously generated to create an organized system, while "chaos" can be thought of as the expression of novelty, the dissipation of entropy that must accompany self-organization. Language is highly ordered with a set alphabet, rules of grammar, and a limited (though constantly changing, to some degree) collection of words. Without these constraints our attempts to communicate fail - there is noise, but no meaning, no information. Words thrown out at random is one end of the scale - it is fully unpredictable, expressing maximum entropy, but containing no information, no meaning because there are no limits imposed by grammar. At the other end of the scale, a repeated phrase is fully predictable, but it is a monotone, expressing no novelty, so no new information. Given the constraints of grammar, language becomes not only organized, allowing us to describe the world and express ideas, but also capable of infinite variation. The entropy of the universe increases; it is dissipated with each new statement through partial surprise. Language is, as Campbell says, "partly predictable and partly unpredictable." Rather than a contradiction or even a paradox, this is more yin and yang, the two contrasting parts that make the whole. Predictable and unpredictable - orderliness and randomness - they are two faces of the same law of nature.

Chomsky has a point about language appearing at a certain stage of biological complexity and being a problem for the biologist; perhaps language competence is a synapomorphy for the entire genus Homo. Unfortunately, it would be difficult to find evidence for this, as the other species of our genus are apparently extinct. (Homo sapiens - "the single wise one" - it's such an inappropriate binomial in so many ways!) Still, some level of language ability may be a defining characteristic for a larger group of primates and not just humans. It's not so startling that researchers have been able to teach hundreds of words of sign language to chimps. It would be far more surprising if our primate cousins were incapable of learning words and expressing themselves through some level of language ability. Human language competence is remarkable and demonstrates emergence, but I'll bet this sophisticated ability isn't really unique to our species. I'm sure the whales and dolphins have nothing nice to say about us, and who could blame them? Furthermore, language competence does not provide any evidence for the notion that we appeared miraculously from a deity. The language capability of chimps is one of many characters tracing our shared evolutionary history with other life forms.

Campbell, being a journalist, takes his examples of emergent phenomena from language, but there are many others. The explanans in the Covering Law Model could include any bunch of molecules, such as water or air, plus an energy source flowing through it, such as heat, plus their interaction with the Second Law. The explanandum is the event of self-organization now expressed by the molecules as a wave or current, existing because of the relationships among the explanans. In a non-living system, once the flow of energy stops, the self-organized structure comes apart and returns to equilibrium. But living systems have special features that differentiate them from the non-living, including the ability to capture their own energy. They also have memory, an intrinsic memory that includes their DNA. But DNA, and the other molecules associated with it, don't "tell" an organism what to become. Rather, the organism builds itself as it translates its stored information into a functioning, living form. Living entities "remember" not only their own development, but also their evolutionary histories. New life remains structurally and functionally "grammatical," as it builds on the memory of the life that has gone before. How else could multicellular organisms ever have evolved? Not from a variation decreasing force such as natural selection, surely.

What a rush of excitement I got from reading Grammatical Man! These concepts were an epiphany. Finally, I was coming across ideas that offered rational descriptions of life and its evolution, ideas not yet fully formed or explicitly linked together, but so tantalizing in their potential for descriptive accuracy and explanatory legitimacy. I think I missed my bus stop.

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