A recent article by Paz-y-Miño and Espinoza made that rookie mistake. And they got called on it. And quite right, too. The letter writers, Rice and colleagues, however, are upset not just because Paz-y-Miño and Espinoza use the theory too loosely.
The first reason they give to separate evolution from the question of the origin of life (a.k.a. abiogenesis) is:
(S)tudents often hold more tightly to a supernatural account for the origin of life than they do to a supernatural account for how the diversity of life arose(.)
This sounds dangerously like self-censorship.
I can almost hear Basil Fawlty’s voice in my head: “Whatever you do, don’t mention the origin of life!”
We talk about the branching pattern of classification as evidence for evolution. We talk about commonalities of living things as evidence for evolution. When you examine those pieces of evidence for evolution, it is a logical inference that life originated on this planet once. To completely separate natural selection and abiogenesis does a disservice to both.
Darwin, as usual, was ahead of the game and saw the two were logically connected. The last chapter of Origin (first edition), he wrote:
(A)ll living things have much in common, in their chemical composition, their germinal vesicles, their cellular structure, and their laws of growth and reproduction. ... Therefore I should infer from analogy that probably all the organic beings which have ever lived on this earth have descended from some one primordial form, into which life was first breathed.
Rice and colleagues also argue that abiogenesis is more the domain of physics and chemistry than biology. This sounds like an easy excuse for timid teachers: “Not my department, have a nice day.”
Scientists working on the origin of life problem are going to be testing hypotheses that life originated following the regular laws of chemistry and physics. That is, they will be testing materialistic hypotheses. Yes, some people are going to have problems with that for religious reasons, and won’t like that science does not allow for the immaterial. Yes, scientists currently have fewer responses to religious objections to abiogenesis.
But there is no point in trying to hide the science around the origin of life under the rug in an effort to get people to buy into evolution. It’s a cowardly way to teach science.
Paz-y-Miño C., G., & Espinosa, A. (2009). Acceptance of Evolution Increases with Student Academic Level: A Comparison Between a Secular and a Religious College Evolution: Education and Outreach, 2 (4), 655-675 DOI: 10.1007/s12052-009-0175-7
Rice, J., Warner, D., Kelly, C., Clough, M., & Colbert, J. (2010). The Theory of Evolution is Not an Explanation for the Origin of Life Evolution: Education and Outreach DOI: 10.1007/s12052-010-0225-1
Graphic by Arenamontanus on Flickr. Used under a Creative Commons license.