Monday, March 1, 2010

Evolution & Christianity, Part II - Critiquing Evolution

III. The Importance of Critiquing Evolution

Now that we have some understanding of what exactly evolution is in its different manifestations, let’s proceed to evaluate evolutionary theory. By far the majority of contemporary scientists (and even contemporary Christians) accept the basic tenets of evolutionary theory in its second manifestation. But there is a substantial, and growing, vocal minority of natural scientists who think that there are too many problems with evolutionary theory, and that it is at best an unproven and at worst a disproven theory. In 1985, Australian biologist Michael Denton published Evolution: A Theory in Crisis, a book which opened the scientific floodgates of dissension towards Darwinism. The chorus of scientists has grown over the past two decades. There are many who doubt the premises and propositions of Darwinian evolution. I want to look at four scientific difficulties with evolutionary theory (one of which addresses only the third manifestation of evolution, the other three of which apply to both the second and third). Through this brief examination, I want to demonstrate that there are good reasons to question the truth of evolutionary theory, particularly when it seeks to become an all-encompassing worldview.

A. The Origin of Life on Earth

Evolution as a worldview argues that evolution is a sufficient explanation not only for the proliferation of life, but also for the origin of biological life on earth. From the 1950s through the 1980s, ‘origin of life’ research was very much in vogue. The struggle, scientifically speaking, is that we have no reason to suspect that life could arise from non-life – other than the naturalistic presupposition that it had to. For decades, experimenters sought to create life in a test tube, or at least produce the building blocks of life from purely natural chemical reactions. But origin of life research has been a spectacular failure, and there are no prospects of them doing any better in the foreseeable future. Stanley Miller’s celebrated 1952 experiments managed to produce a series of amino acids from a reconstructed facsimile of the ancient earth’s atmosphere. Amino acids are one of the fundamental building blocks of proteins, which in turn are one of the fundamental building blocks for life. Thus, Miller’s success in ending up with amino acids was heralded as the first in a projected long line of success stories in which origin-of-life experimenters would manage (eventually) to create life in a test tube. However, Miller’s experiments (and subsequent ones) are useless in providing a model for the origin of life.

First, Miller’s amino acids are useless to form life – amino acids need to be of a particular type, need to react with one another in a chain, in a very specific manner and sequence. Yet in laboratory experiments, all we get are scrambled, random sequences. There’s no natural force capable of selecting the right amino acids and lining them up in the right order. As a result, the proteinlike chains that appear in the test tube are useless for life. Second, the experiments do not mimic environmental conditions on early earth – scientists choose only certain chemicals, in their pure form, to put in the test tube. On early earth, other chemicals would have been around as well, they would not have been in their pure form, and other chemical reactions would have interfered.

Third, amino acids are delicate, and would likely be broken down into their constituent elements in nature; in the test tube, the scientist plucks them out to protect them. Indeed, when Miller (and other origin-of-life researchers) did not intervene, amino acids broke down just about as quickly as they were ‘created’. Fourth, when scientists seek to proceed from amino acids to proteins, they use fresh, pure amino acids, choosing the right ones. They have never gone from simple chemicals to amino acids to proteins in one experiment, even using rigged environmental conditions. Thus, even the most successful origin-of-life experiments tell us next to nothing about what could have happened under natural conditions. They tell us only what happens when a brilliant scientist manipulates the conditions, ‘coaxing’ the materials down the chemical pathways necessary to produce the building blocks of life.

The experiments prove that even the preliminary building blocks for life can be created only by an intelligent agent directing, controlling, and manipulating the process. And even then, our human intelligent intervention can only go so far. We cannot derive life from non-life.

B. The Intractable Problem of Speciation

Darwin’s theory of descent by random mutation and natural selection from a common ancestor is an exercise in logical extrapolation. From observed variation within species (adaptation), Darwin (and many others) inferred that the process of adaptation, when extended over a long period of time, would result in speciation – the evolution of an entirely new species. Gradual, incremental changes would accumulate, and eventually new species would result.

Basically, what I call the ‘intractable problem’ of speciation is that this aspect of evolutionary theory is simply a hypothesis which has not been confirmed, or observed in progress. Despite over a century of intense scientific experimentation, suggested examples of speciation are almost non-existent in the scientific literature. Those instances of speciation which have been observed involve viruses, and still result in, what to our mind anyway, would be minor changes – more along the lines of adaptation rather than cataclysmic evolutionary change. From my perspective, I am not even sure that they are legitimate examples of speciation – but rather evidence of alteration within species. Despite their best efforts, scientists have not been able to produce or observe trans-speciation. Fruit flies, with their short reproductive span, have been experimented on exensively, and extraordinary offspring have been produced. But whether the resultant fruit flies have two wings, four wings, six wings, no wings, or a hundred wings; they remain fruit flies. Ditto for scientific direction in the reproduction of dogs, cattle, flowers, etc. Specimens do not evolve into new species. You don’t get cats from dogs. In other words, evolution (transcending current species boundaries) remains a hypothesized theory which has never been seen to happen. It appears, from my perspective, as if Genesis 1:20-24 gets it right – God created the living things ‘according to their kinds’. There is incredible diversity of kinds, and remarkable adaptation and variation within those kinds; but animals do not evolve from one kind into another.

Another way of putting this is that speciation – the heart of Darwinian evolution – is (a) unobserved; (b) unverified in scientific experimentation; and (c) unfalsifiable. I suggest that this is the textbook definition of an unscientific theory. In other words, Darwinian evolution is not science, but rather philosophy or worldview.

C. The Fossil Record

When Darwin published his theory, he expected that the new field of palaeontology (the study of fossils) would eventually bear out his theory. He predicted that there ought to be countless numbers of intermediate species in the fossil record – records of living organisms which represented the transition between, for example, reptiles and birds. This theory has not been borne out by the fossil evidence, however. While there have been a few highly-publicized examples of proposed transitional species, some of these examples have later been exposed as fraudulent or over-blown. There are a few remaining possibly legitimate examples of transitional species (although as a non-evolutionary theist I would interpret that data differently); but there is certainly nothing like the plethora of transitional fossils that Darwin insisted would have to be there to support his theory. In other words, the fossil record serves to disconfirm evolutionary theory.

Even more troubling is the Cambrian explosion in the fossil record. The Cambrian explosion refers to the geologically sudden appearance of complex animal life that marks the beginning of a rich and dense fossil record. Prior to the Cambrian age, there are no fossil records of the complex vertebrates; suddenly in the Cambrian strata, there they are: fully formed, stable, and relatively unchanging from that point onward. Moreover, each phylum is self-bounded – not apparently related to any earlier type of fossil species. Rather than a tree of life (Darwin’s picture) that traces back to a common ancestor, you have instead the picture of a sudden sprouting of a whole field of various wildflowers with no precursors. In other words, what we see in the fossil record is not a gradual evolution and diversification of life forms, but rather a sudden appearance of fully-formed species and families of species.

So in two distinct but powerful ways, the fossil record, which was supposed to be the primary evidential support for the theory of evolution, instead challenges Darwinism.

D. Irreducible Complexity

Darwin also admitted, when he proposed his theory, that any irreducibly complex organ or system would provide a devastating blow to evolution. Darwin did not believe that any such organ or system existed, but many contemporary biologists do. Irreducible complexity can be defined as “a single system that is composed of several interacting parts, where the removal of any one of the parts causes the system to cease functioning.” (Behe, Darwin’s Black Box, 93) A mousetrap is the famous example. Behe argues that there are large numbers of irreducibly complex biological systems within our bodies, ranging from the eye, the blood-clotting mechanism, to the bacterial flagellum, and so on. These systems defy evolutionary explanation, as they require the entire fully-formed structure to appear simultaneously to be of any benefit to the organism. A partial flagellum is not only useless, it is positively counter-productive, and would serve to make the organism less suited for survival.

E. Human Sociality – Ethics and Religion

I will be spending significant time and space discussing both of these facets of human existence in later posts, so I will only mention them briefly here. Evolution as an overarching worldview (or metanarrative, if you like fancier words) claims to explain morality and religion as well as biological diversity. To put it simply and bluntly, evolution is highly inadequate to do the job that is required of it. Evolution fails to explain the unquenchably religious spirit of humanity, and similarly fails to explain the undeniable existence of a transcendent, objective standard of morality of which we are all aware (and which, simultaneously, we all fail to live up to). Discussion of these issues will have to wait.

The end of the matter, however, is simply this. Evolutionary theory, in its simplest form of adaptation, or variation within species, is uncontroversial, perfectly compatible with Christian theism, and absolutely correct as a scientific theory.

Evolutionary theory as an overarching worldview, seeking to explain the origin and structure of the universe, the origin of life on earth, the existence and nature of human morality and religion, is unquestionably in conflict with Christian theism. It is also patently false and unworkable.

The second manifestation of evolutionary theory – macro-evolution or classical Darwinism – holds that all living things have evolved from a common ancestor through a gradual process of random mutation and natural selection. This theory is potentially compatible with Christian theism, if random mutation is altered to be understood as a divinely-guided mutation which appears random to the human observer. However, in the end it really doesn’t matter whether the theory is compatible with Christianity or not. From my perspective, at least, this form of evolutionary theory fails as well. The inability of scientists to observe or recreate speciation, the contrary evidence from the fossil record, and the obstacle posed by irreducible complexity all conspire to render evolutionary theory as questionable at best.

From an apologetic standpoint, the implications are immense. Evolution has a strong hold upon contemporary society – many students abandon their faith because of the perceived strength and unassailability of Darwinism. If only students could be shown the contrary evidence, which demonstrates significant problems within evolutionary theory, perhaps we could close that back door of the church. This is a matter of giving struggling Christians “reasons not to disbelieve,” or, if you prefer, “reasons to continue believing.” In the beginning God created the heavens and the earth. The earth is the Lord’s and the fullness thereof. Evolution doesn’t explain everything. Christianity does.