So far we’ve watched two sides slug it out over the idea of evolution: the materialistic scientific side seeing evolution as a concept freeing humans from religion as “an artifact of the childhood of humanity, a childish belief which it was now necessary to discard”, and the creationist side confronting evolution as a “’secular-humanistic’ teaching which will ultimately erode the American way of life”. Choose sides: evolution as an enabler of the maturity of human society or a corrosive force which undermines society.
But, we’ve also seen a ‘middle ground’, typified by the more centrist expressions of the ‘liturgical’ religions which do not take issue with the basic premise of evolution itself, but insist that evolution is part of the works of a personal God.
Thus, on the subject of religion and evolution, we really have three sides: evolution as diametrically opposed to religion, religion as diametrically opposed to evolution, and religion and evolution ‘accommodating’ each other.
Today we’ll look more closely at the concept of evolution itself at how this straightforward idea can be perceived in such diverse ways, and offer some critiques of these different interpretations.
There are many ways to approach Darwin’s basic theory of natural selection. I’m choosing that of Dr. Kenneth Miller, Catholic Professor in the Department of Molecular Biology at Brown University. Dr. Miller is clearly at the center of this war. He is neither wedded to many of the metaphors, elements of sentimentalism and scriptural literalism so criticized by such militant atheists as Richard Dawkins, nor is he vague in his belief in a transcendent and immanent personal God. His books on evolution and belief, Only a Theory and Finding Darwin’s God are recommended to anyone looking for a deeper dive into this complex issue.
“At its heart, evolution is a modest idea, a minimal concept, just two points really: First, the roots of the present are found in the past; and second, natural processes, observable today, fully explain the biological connections between present and past. On purely scientific terms, these two points leave very little to argue about.” In the process of evolution, “favorable variations increase the likelihood of success in the struggle for existence, and therefore natural selection automatically chooses those characteristics best suited for survival and weeds out those that are least helpful.”
Effectively, entities beget offspring, some of which survive to continue procreation, and some do not survive. Over time, this process of procreation in successful lines of lineage undergo small changes, which over longer periods of time result in entities quite different from their distant ancestors.
At the ‘macro’ level (the level of our lives), this is certainly a straightforward concept. But, the question can be asked, “how does it work”? In order for life to change and ‘adapt’ to its surroundings, what has to take place? What are these ‘natural processes’?
Much is still being learned about the biological processes at play in the intensely complex “micro level” workings of the cell, but significant breakthroughs have occurred with the discovery of the mechanism of heredity: the gene. With the increasing detail of analysis of the cell at the molecular level, it has been discovered that genes are ‘digital’, which means that they are composed of a small number of specific molecules which appear in various sequences. Genes, in effect, are written in a sort of ‘language’, referred to as DNA. The contents of this language effectively tell the cell how to make its building blocks, essentially other molecules, known as amino acids which compose the proteins which are the biochemical workhorses of the cell.
Each time the cell divides, which is the essential action in the growth of a multi-celled entity, the entire language must be copied and replicated in the new cell to insure an identical set of genes in the new cell. Occasionally, due to small mistakes, or the intervention of an outside source of energy (such as radiation in the environment), the information does not accurately transfer, resulting in a ‘mutation’. From Dr. Miller:
“Mutations, acting upon that digital genome, produce variation, the raw material upon which natural selection goes to work. Since mutations can duplicate, rearrange, or change literally any gene, it follows that they can also produce any variation.” “Natural selection favors and preserves those variations that work best, and new variation is constantly generated by mutations, gene rearrangements, and even by exchanges of generic information between organizations.”
This, of course, is one stimulus to species change. Another, more important and significantly faster, is that of environment change. Many studies have shown a significant change to a controlled population, such as the study performed on guppies by the biologist Davit Reznik. Reznik moved a population of guppies from one forest pool to another which had a different predator fish. He was able to show that over eleven years the surviving guppies had changed in significant ways to increase in their survival rate.
Thus from ‘within’ and ‘without’, living things, given enough time and stimuli, can be seen to show changes in their DNA significant enough to warrant the title of, “new species”.
“Survival of the Fittest”?
This statement, of course, is one most closely associated with Darwin’s theory of natural selection, although coined by Herbert Spencer (late eighteenth century “Social Darwinist”). Those which survive go on to procreate and their survivors successfully procreate, and so on. By definition, we are the survivors of successful ancestors.
The atheists make much of this: we are the sum of random mutations which have survived the ravages of our environment: we are by definition, “the fittest”.
The question that this raises, of course, is what is the definition of “fittest”? Many scientists would say that the end goal (if such a thing can be ascribed) of natural selection is, “survival”. In this way of thinking, the evolutionary pathway to the human, with his vulnerable physiology and relatively short life span, cannot be considered a paradigm of ‘survival’ as compared to other living things.
For instance, since humans consist of a complex amalgam of organs, we are totally dependent upon large families of billions of entities known as ‘bacteria’ that perform myriads of operations (such as the extraction of nutrients from food). Many of these essential bacteria, while very simple, nonetheless can have lifetimes much longer than the seventy or so years of the human host. They can precede our birth (we get them through our mothers) and survive our death. Most bacteria are thought to have occurred in evolution much earlier than the human person. If the objective of evolution is ‘survival’, why does it continue past the advent of bacteria? Looked at the other way around, is it possible that humans evolved only to provide a host for the bacteria?
At the purely material level, it is thought that atoms have no natural death. If left to themselves (e.g. if they do not end up smashed to bits in a particle accelerator), they will not die. Many of the atoms in our bodies (at least the heavier ones, such as carbon) started their life in the explosion of some star several billion years ago. After you die, they will even outlast the long-lived bacteria in your gut. This is ‘survival’ on steroids. Why does evolution continue to proceed past this point, having accomplished an entity of such monumental stability?
More than Just Biology
Conventional scientific thinking, as summarized above, understands evolution as something that happens in living things, starting with the cell and more or less slowly proceeding in the human person through minute changes in our genes. However, this conventional point of view limits evolution to something that somehow pops up out of nowhere in the most recent three percent of the unfolding of the universe. What about the fourteen-some billion years prior to the appearance of the cell?
So to understand evolution in the correct context, we must understand it as occurring in three stages:
Pre Life: Physical entities united by forces described by physics and chemistry.
Life: Biological entities united by forces described by Darwin’s Natural Selection.
Conscious Life: Human persons united by Darwinistic influences?
To recap, most of science considers evolution as it occurs through Natural Selection in the era of life. The materialists consider Natural Selection to still be in play in the era of conscious life, the creationists see it as a step on the slippery slope to cultural decay, while the centrists are willing to accommodate it as long as the action of God is understood as the ultimate force behind it.
Next time we’ll continue our look at evolution by overviewing Teilhard’s more comprehensive and inclusive vision of evolution as a process which can be seen to unify the cosmos which naturally accommodates the human person.