For some reason, I have felt compelled to write on evolution today. I have mostly avoided the topic for almost 15 years, possibly out of my embarrassment for some of the ways in which I argued on this topic as an apologist for Christ when I was a younger man. At any rate, I have been meaning to write on evolution for a long time and today has become the day.
If I was to assess the evidence for evolution vs the evidence for creation in some abstract quantitative way, then the figure above would illustrate my assessment of the evidence. There are no numbers on this figure and it is entirely subjective, but as you can see it illustrates my view that the weight of evidence for evolution vastly overwhelms the weight of evidence for creation. And yet I would say that my belief in God’s guidance of the evolutionary process is strongly supported by the evidence. How do I explain this seeming contradiction?
The answer is that there are a number of issues that get “lumped together” in discussions of “evolution”. These issues are:
- The Age of the Earth
- Common Ancestry
- Natural Selection
- Random Mutation
Let us discuss these issues one at a time.
The Age of the Earth
The evidence for the age of the earth is simply overwhelming. Any belief that the earth is younger than billions of years old relies almost entirely on bogus evidence or anti-realistic theologies such as the “Appearance of Age” argument. I have never seen a single compelling argument that suggests the earth is only a few thousand years old and I have seen a great deal of evidence that suggests a much older age. Any theology that holds that the earth is only a few thousand years old is entirely incompatible with reason and science.
The evidence for the common ancestry of all modern organisms is vastly less powerful and compelling than the evidence for the age of the earth, but it is still extremely powerful and compelling. From the evidence of shared genes to the remarkably similar stages that organisms go through during embryonic development, common ancestry is difficult to deny.
Natural selection is the process whereby the population of a given set of organisms adapts to its environment over multiple generations through the differential survival of the individual organisms most well-adapted for that environment. This process is mathematically unavoidable given a small set of assumptions and readily observable in nature. It is not possible to deny that natural selection constantly acts to shape populations in the real world all around us every day.
Random mutation occurs when copying errors are made in the process of replicating genetic information during cell division. The process undeniably occurs and is responsible for effects ranging from aging and cancer to bacterial resistance to antibiotics. This process is observable in the world around us and is also undeniable on the basis of the evidence.
When gene frequencies change in a population of organisms with a common ancestor due to mutation, selection, gene flow and genetic drift, micro-evolution is said to have taken place. Over time, these differences can cause a parent population to separate into different populations that are no longer capable of inter-breeding and this is called speciation. Though these claims are often contested by those who believe in a more active divine role in creation, the evidence for this process in nature is quite strong.
According to evolutionary biologists, macro-evolution occurs when micro-evolution causes large scale changes in organisms over geological time. It is over this issue that the differences in belief between an unguided evolutionary process and a guided evolutionary process are at last discernible. To a person who believes in a guided process, merely random mutations would be incapable of creating the spectacular diversity of life on earth. To the person who believes in an unguided evolutionary process, random mutations are all that is available and every organism that has ever lived must have come about through small variations in an extremely gradual process.
Now it is to be stressed that a belief in a guided evolutionary process does not necessarily mean belief in explicitly supernatural interventions. As shown by the the following verses in the Bible, sometimes a miracle is only the fortuitous timing of an event (or sequence of events) that is completely explainable by natural processes.
Then Moses stretched out his hand over the sea, and the LORD drove the sea back by a strong east wind all night and made the sea dry land, and the waters were divided. (Exodus 14:21)
and suddenly there was a great earthquake, so that the foundations of the prison were shaken. And immediately all the doors were opened, and everyone’s bonds were unfastened. (Acts 16:26)
Asking the question, “Can an unguided process of evolution have created the spectacular diversity of life on earth?”, therefore, inverts the assessment of evidence for evolution vs. creation that I discussed earlier. (Creation in this context meaning a guided evolutionary process.)
How can this be? Because most of the evidence for “evolution” is gone but most of the difficulties that make evolution so problematic for an unguided process remain. An in depth discussion of this evidence, however, will have to wait for another day.