In response to “Evolution: theory, not fact,” in Feb. 7 edition of Technician. Do you believe in the theory of gravity? This fatuous question is of the same form creationists use to begin arguments designed to deny the facts of biological evolution. Evolution is indeed a fact, and there are theories employed to explain how we think it works—most famously, Darwin’s theory of evolution by means of natural selection. There are other theoretical aspects to evolution as well, such as Hardy-Weinberg equilibrium theory, the theory of punctuated equilibrium and others.

There are theoretical aspects to gravity, as well. But few rational people would deny the existence of gravity, and few biologists deny the existence of evolution.

Perhaps it should be pointed out, at the risk of pedantry, just what a theory is. A theory is a man-made explanation, and as such, cannot be proven or disproven, only supported or refuted. Darwin’s theory of evolution by means of natural selection is a theory and is well supported from evidence seen in nature and from designed experiments. Evolution itself, on the other hand, is a fact, like gravity. Paul Schwartz retired school teacher