1.8 Theories of Evolution

Theories of Evolution

Having mentioned several different theories of creation, I will move on to discussing several facets of the “theory of evolution”; actually several different theories, as understood by the scientific community. Although I haven't tried to focus this blog on the narrow topic of “creation vs. evolution,” that is a common topic of discussion. However, it’s not enough to just speak of the “theory of evolution” as a whole -- often those who do, tend to lump a lot of things together that are actually different things and should be considered individually. We need to clarify the definitions of the various types and varieties of evolutionary concepts in science, in order to identify what kind of evolution we are speaking of and consider how to properly address them.
See Craig Rusbult, “Evaluation of Evolutions” (http://www.asa3.org/ASA/education/origins/evolution2.htm) for links to many resources on these topics.

Some of the meanings of evolution include the following (see “A Voice For Evolution As Science”, http://www.asa3.org/ASA/PSCF/1992/PSCF12-92ASACouncil.html; Keith Stewart Thomson, “The Meanings of Evolution”, American Scientist, Vol. 70, pp. 529-31, Sept-Oct 1982):

1. the general concept of “change over time”; this is a very broad definition, and includes a lot of things which are simply not controversial, even for Biblical fundamentalists.
2. the hypothesis that all “organisms are related through common ancestry”; this is one of the fundamental concepts of biological evolution, as suggested by Charles Darwin and others.
3. a theory proposing a particular explanatory mechanism for the pattern and process described in (1) and (2). For any scientific theory, different hypotheses are suggested and modified over time based on the evidence. Some of the things Darwin suggested have been discarded, modified and supplemented over the last 150 years, so that “Darwinism” is no longer a useful term, unless referring specifically to Darwin's particular beliefs. The term “Darwinism” is no longer used much in scientific literature, and it is mainly used today only in a perjorative sense by creationists.
4. a scientifically focused concept of populations adapting to changing environments;
5. a religiously value-laden tenet of naturalistic faith, that “Man is the result of a purposeless and natural process that did not have him in mind” (George Gaylord Simpson, The Meaning of Evolution, 1967, p. 345.).

This last “meaning” of evolution should be recognized as a philosophical statement of belief, not a scientific hypothesis or conclusion. To say that natural processes are “purposeless” and that man is “simply” a result of these purely physical processes, is clearly beyond the scope of what science can legitimately conclude. Yet, some scientists insist on promoting this philosophical view in the name of science. Many creationists accept this false definition, helping blur the distinction between science and philosophy.

1.7.4 Theistic Evolution

Theistic Evolution (TE)

Another common belief among Christians is “Theistic Evolution”, or “evolutionary creation”. They believe the biological and fossil evidence indicates that natural processes were the physical processes (secondary causes) by which species came about over time, yet they acknowledge God as the primary cause of all things. In this sense, they agree with the “theory of evolution” (the science) in what it says about the biological history of life on earth, but rejects the conclusions (philosophical materialism) of atheistic scientists who conclude that there must be no God. Theistic Evolution doesn’t generally propose an alternative science to mainstream scientific consensus, as the other forms of creationism do, but proposes that the natural mechanisms within nature are just the part that we can understand scientifically. God’s action and providence are not meant to be understood through scientific formulas and processes.

For instance, one proposal is that God created this beautiful and complex world with inherent capabilities to be able to spontaneously produce life under the right conditions, and modify and adapt genetically to grow new forms and species of plants and animals. God did not directly create the visible universe through what we would call supernatural intervention. Instead, He acted indirectly through the design of the universe that was capable of producing structure and order as we see around us. God’s providence was expressed in the physical creation by “building in” the potential for it to develop as it has, and He still manifests His providence in sustaining us in our spiritual relationship to Him. This view credits God with such amazing creative ability that He could encode into the fabric of nature itself the ability to spontaneously develop all that God had decreed from the beginning, and doesn’t require God to “tinker” with the machinery along the way to keep it going on a certain trajectory. It doesn’t necessarily deny that God can or does do miracles, but claims that such interventions are not normally necessary. (An extreme form of this view is essentially what is referred to as "Deism," the idea of God as a Watchmaker who wound up the creation at the beginning, but no longer interacts with it directly.)

Another form of TE, and in some ways almost opposite of the view above, is that God’s presence in creation is completely pervasive. That is, rather than God creating the universe and then letting it spontaneously develop, or once in a while stepping in to make a special act of creation (forming the earth, creating a new species, etc.) as in other forms of creationism, God and His providence are present all the time in guiding creation toward accomplishing His purposes. He is intimately “in and through all things” and continuously involved with every aspect of the creation, but at a level that we cannot perceive scientifically (or at least not easily or often). The physical processes of creation are simply the means through which God is accomplishing the outward development of the universe, and His grace is similarly pervasive in working out His spiritual will within our lives. Thus, all the evidences for physical creation and development might one day end up being describable scientifically and have the appearance of purely “natural” forces, but God is working at a lower level which is not scientifically detectable.

Another variation on Theistic Evolution suggests that the apparent randomness in quantum theory, chaos theory, and other as yet unknown processes such as genetic mutation are some of the means through which God can effect specific outcomes or general variation and development within creation, and yet his actions can remain hidden behind processes that appear random to us. God could cause a genetic mutation, or a quantum event at an atomic level, which is to us simply within the range of random probability, so that He remains undetectable and yet active in moving creation forward toward His will, both in terms of stellar and planetary creation, and biological diversity culminating in humans who can comprehend His ways and bear His image.

There have been many proponents of the various forms of Theistic Evolution, from Alfred Russell Wallace and Asa Gray (contemporaries of Charles Darwin), Pierre Teilhard de Chardin, and many modern writers including Keith B. Miller, Kenneth R. Miller, Francis S. Collins, Denis Lamoureux, John Polkinghorne, Simon Conway Morris, George Murphy, Alister McGrath, and Howard Van Till.

1.7.3 Intelligent Design

Intelligent Design (ID)

A theory which is gaining a lot of popularity in the media recently is “Intelligent Design” (ID). Strictly speaking, ID is not a creation theory in the same sense as the others discussed. Intelligent Design generally consists of showing exemplary features of the natural world that seem to be clear examples of designed structures. These are presented as counter-examples to traditional Darwinian evolution, which is said to be based on undirected, step-by-step genetic modification and natural selection. Intelligent Design advocates emphasize a concept of “irreducible complexity,” and on the fine-tuning arguments of the basic laws of nature by asserting that the fundamental properties of nature are finely tuned to allow for the development of matter and living things.

The theory of “irreducible complexity” involves looking at the complex mechanisms evident in the physical world where various parts of an organism are interdependent on one another, and questioning how each of those parts could have formed gradually over time. Some structures appear to be so complex that there is no way that they can be reduced to individual parts without destroying the whole, and no conceivable mechanism by which they could have developed step by step over time. By implication, there is no way for one part to have developed over time by evolution, while waiting on the other part to be developed later, because the organism could not survive without all the parts having been put into place all at once. A classic example given by Michael Behe is the bacterial flagellum, which is effectively a small outboard motor that propels the bacteria’s motion, where all the parts are claimed to be necessary before the mechanism can be of any benefit to the organism.

Strictly speaking, there is a difference between the belief in “intelligent design” and the “Intelligent Design” movement. Those who hold a YEC belief automatically believe in intelligent design, because they believe God miraculously created and designed all things. Similarly, advocates of OEC who believe in special creation and/or divinely manipulated genetic modification, also accept the principle of design. Even Theistic Evolutionists (to be discussed next) would claim there was a very intelligent design which went into designing a universe so complex that it could develop life and complexity through natural processes, or through the pervasive but hidden activity of God’s providence.

The Intelligent Design movement is distinct from any of these, and involves an overlap with all the other creation theories, and even includes those who are not Christians or theists. Many of its adherents accept the scientific evidence for an old earth and biological evolution, although people from the YEC view definitely use the concepts of irreducible complexity and fine-tuning as well. Often the ID movement makes special emphasis that they are not promoting a religious theory at all, claiming not to make any specific identification of the intelligent designer. Its main claim is that certain things may be detectable as being intelligently designed, as opposed to arising naturally through purely material causes and effects.

The most prominent ID organization is the Discovery Institute (http://www.discovery.org).

1.7.2 Old Earth Creation

Old Earth Creation (OEC)

So-called “Old Earth Creation” (OEC) or "Progressive Creation" acknowledges the scientific evidence which points toward an earth that is approximately 4.6 billion years old, and a universe which is approximately 13.7 billion years old. During the long history of nature, God intervened miraculously (or supernaturally; that is, outside the normal course of natural cause and effect) to perform acts of special creation. In particular, the appearance of first life was an act of divine creation, rather than occuring through natural processes, and the creation of mankind was another act of special creation, rather than through evolutionary development from earlier forms of hominid.

Along with YEC, the OEC view often advocates a strong “concordism”. That is, the Bible is reconciled to science in such a way that the Bible account in fact agrees with the scientific account. In order to reconcile this view with the first chapter of Genesis, some OECists claim that a “day” of God’s creation was actually an extremely long unspecified period of time, corresponding with the scientific evidence for the origins of light, planets, flora and fauna, and mankind.

One variation of OECism says that at various points in time, God acted with independent acts of creation, creating “from scratch” various organisms, species, and people. This would mean that each species would not have a direct biological inheritance from older species (as predicted by the theories of evolution), because each species was specially created; or at least, most importantly, that mankind is distinct from other species.

Another variation of OEC agrees that the earth is old and there is a progression indicated in the fossil from older to more recent species, and that God brought about the creation of species by extensive modification of existing genetic material (adding, deleting, modifying genes in existing species to create new species over time). In effect, this view recognizes the genetic and fossil evidence of gradual change in species, but claims that it was specific, miraculous acts of God in history which caused this development. This perhaps begs the question of whether science could detect the difference between supernatural “tweaking” of the genetic code versus natural effects causing the variation.

One organization which promotes an OEC view is Reasons to Believe (http://www.rtb.org/), founded by astronomer Hugh Ross. See also a list of quotes from 100 “Notable Christians Open to an Old Earth Interpretation”.

1.7.1 Young Earth Creation

Young Earth Creation (YEC)

What is generally referred to as “creationism” in the popular media as well as many Christian circles, is actually only one specific form of belief about creation -- “Young Earth Creation”, which we will abbreviate YEC. This is the view that God miraculously created everything in essentially its current form within six 24-hour days, sometime approximately 6000 years ago. Along with this view and companion to it, is the idea that the flood of Noah was a universal, worldwide deluge in about 2300 B.C., which destroyed most living things including all humans and animals over the whole globe, and formed most of the world’s fossil record and geological features. Adam and Eve were the first humans and the ancestors of all humankind, and their sin changed the nature of the physical creation so that animal and human death were introduced into the world.

YEC depends generally on a literal, face-value reading of the accounts in Genesis. All evidences from science which disagree with a young earth and universe must therefore be explained in some way. There is some disagreement over the exact details among those who hold a YEC view. Some reject all contrary scientific evidence and claim that any appearance of greater age in nature is simply because God created it in something like its present form. Others try to avoid "appearance of age" arguments and instead propose various mechanisms to account for the evidence. Most modern-day proponents of YEC generally accept so-called “microevolution” (small adaptations within species over time), but not biological evolution between species. However, as will be discussed later, some modern YEC proposals suggest extremely rapid evolution of species (or sub-species) after the flood, as a means of explaining the vast biological diversity without requiring millions of species on the ark.

YEC proponents include Answers in Genesis (www.answersingenesis.com), the Institute for Creation Research (www.icr.org), and many other organizations and individuals. Often YEC is presented as the only alternative to full naturalistic evolution, and the only truly Christian approach. I will discuss these claims later. For now, it will just be noted that “young-earth creationism” is but one of several positions on science and theology held by committed Christians.