Who or what is driving evolution?
In a post entitled What is evolution? Prof Moran provides a one-liner definition of evolution:
Evolution is a process that results in heritable changes in a population spread over many generations.
This is a good working scientific definition of evolution; one that can be used to distinguish between evolution and similar changes that are not evolution. Another common short definition of evolution can be found in many textbooks: “In fact, evolution can be precisely defined as any change in the frequency of alleles within a gene pool from one generation to the next.” Helena Curtis and N. Sue Barnes, Biology, 5th ed. 1989 Worth Publishers, p.974
That definition is extremely general. It is simply telling us that heritable genes change from generation to generation; over long enough time this change is likely (but not necessarily) to entail phenotypical changes as well. It is notable that this definition stops short of stating just what produces the change. In fact this catch-all definition is not much stronger than saying that organic forms change over time: Because the fossil record betrays phenotypical changes over long periods this in turn implies genetic change and therefore evolution. It follows then that the fossil record is strong evidence that evolution, in the very general sense of mere change, has occurred.
So, given this background we can see why here the good Prof writes:
Neil deGrasse Tyson said that the theory of evolution is a fact. This is not correct. Evolution is a fact. Evolutionary theory attempts to explain how evolution occurs. Some of the explanations, like natural selection, are facts but many aspects of modern evolutionary theory are still hotly debated in the scientific community.
That’s intriguing; so Larry accepts that the detailed engine/mechanism of evolution is a theory and not a fact! Too true! But the definition of evolution he has given is so general that it could also include changes due to the tinkerings of a homunculus intelligent designer or anything else for that matter!