Radio talk show discussion on common descent

One of the things I am interested in is the common “man in the street” objections to the theory of evolution. A very common concern is the “micro” vs. “macro” distinction: many people can accept evolution within a species, but just can not see how one species can ever evolve into something else. Such people therefore can not accept common descent, which is a central tenet of evolutionary theory.

I’ve recently had two interesting encounters with this: one last week during an appearance on a conservative radio talk show and the other in response to an unsolicited email from a member of Dr. Kent Hovind’s staff. In both cases I was met with considerable resistance to the obvious question of “if common descent isn’t the means by which new species have came into existence, then what is?” The obvious answer - the one which was the default historically before the theory of common descent and the one held by many anti-evolutionists today, is special creation: creation ex nihilo, the immediate materialization into existence of new organisms. However, as the following encounters show, anti-evolutionists are reluctant to put this on the table as an actual “competing hypothesis.”

In order to illustrate, I would like to summarize these two encounters, the first here in this post and the other in a second, separate post.

Thursday, December 30 I was on the Jerry Agar Show, a conservative talk show on radio KMBZ in Kansas City, to talk about evolution. We had agreed that I would try to answer some of Jerry’s questions about evolution, and that the subject would not be intelligent design, religion, or the politics of state science standards - we would focus on Jerry’s concerns about the “holes” in evolutionary theory. I was interested in seeing what ideas Jerry felt were most worth discussion, so I was quite willing to let him lead the way.

Unfortunately KMBZ does not archive their shows on the internet. I did, however, record the show for myself so that I could listen to it later. Here are reflections on my experience.

Jerry opened the show with a standard introduction:

Should we teach evolution? … and evolution only? Should we teach creation? … creation only? Should we teach both? … and trust that young people can actually make up their own minds, given all, or at least both, of the two prevalent theories of the world.

Now, one of my purposes for going on this show was to try some different approaches to discussing evolution with those that don’t accept it. Instead of letting myself be put on the defensive, I wanted to be more proactive. Therefore, early in the show, I asked Jerry,

What exactly about evolution do you not accept? Do you not accept there has been common descent?

After verifying that he accepted an old earth - Jerry is not a young-earth creationist, Jerry said,

I have no problem with adaptation within species. That can be proven. But you can take thousands of generations of e. coli bacteria and still come up with nothing more than e. coli bacteria. There’s been no demonstration that I’ve been able to see, other than theory*, of a species becoming another species.

* As Jerry and I discussed later in the show, he was using the word “theory” here in the common sense of speculation or unproven guess. This confusion between the common meaning and the scientific meaning of “theory” continued throughout the show

So now we had the basic issue before us: “macroevolution” - evolution of species, is an undemonstrated and speculative guess, and therefore common descent is also.

Then I started to ask Jerry another question:

If you don’t think that evolution can take us beyond species, then a scientist has to ask, “what’s the alternative explanation.” What do you think has happened to create …,

but Jerry interrupted me with,

No, wait a minute. I don’t have to have developed a workable theory of how the earth was formed, how the various species came to be, in order to think evolution is wrong…. Just because I don’t have a theory that is better than evolution doesn’t mean evolution is right*.

(*By the way, Jonathan Wells gave this same response when I asked him the same question at the IDnet’s 2002 DDD conference.)

I spent the next few minutes discussing the fact that scientists for over 150 years had been testing the theory of evolution and its competing predecessor theory, special creation, against the evidence, and that overwhelmingly the theory of evolution had been accepted and special creation had been rejected.

Again, Jerry resisted this attempt on my part to look at “the competing hypotheses” - to compare evolution with some other explanation. At some point, he said,

But you’re trying to bring this back to “you guys who believe in creation are wrong.” I’ve never told you I believe creation is the correct explanation. I’ve told you that I don’t think your theory has proven itself out completely.

But later he added,

Why does so much almost religious zeal come from evolution people such as yourself to avoid talking about any other theories.

Now notice the inconsistency here. On the one hand, the point that one doesn’t have to know what is right to think something else is wrong has some legitimacy - the conclusion “I don’t know” is an accepted position in science.

On the other hand, notice that it is Jerry who is avoiding discussing these other theories! He starts the show asking if we should teach evolution, or creation, or both; he then says that he doesn’t have an alternative theory, hasn’t taken a position on creation, and doesn’t need to to critique evolution; but then he berates me (religious zeal being a pretty strong term) for not being willing to discuss the alternative theories.

But comparing evolution with its alternative, special creation “theory”, had been exactly what I was trying to do, and he wouldn’t do it.

Later in the show I made this point explicitly, and the conversation went like this:

Krebs: “Here’s an inconsistency in your position I’d like to bring up. You have said we should teach other theories other than evolution in …”

Agar: “No I didn’t.* I said you should be open to them and not as close-minded as I see the scientific community being, and again, I’m not saying this is an either-or thing. I’m wanting you to demonstrate that evolution is a theory proven enough that it should be so exclusive.” (*Yes he did, or at least he implied we should consider doing so in his introduction when he asked whether we should teach evolution only, creation only, or both.)

Krebs: “OK, so then what I came back with was that it can only be compared to other theories, and you said you didn’t need to have any other theory - you just had to say there’s problems with this one.”

I’ve taken the time to dissect this conversation because I think it illustrates a number of “man on the street issues.”

Notice there is a tension between wanting to “teach other theories” and wanting to teach the “weaknesses” of evolutionary theory. What many anti-evolutionists want is to show that evolution is scientifically invalid, but they really have no scientific theory to replace it with; as has been made explicit by Dembski and others, once design (or creation) is established from the invalidation of evolution, theology takes over - no more science is necessary. Therefore, they don’t really want to talk about “other theories,” because that brings up the religious ideas they are trying to avoid having me part of the discussion.

The confusion about the word theory plays into this tension. The scientific word implies that we have observations, hypotheses, demonstrated means of testing those hypotheses, etc. The common meaning of theory, however, allows one to hold a speculation or opinion without any rigorous testing against evidence. Asking them to discuss their “theory” of creation (or design) from a scientific point of view makes them uncomfortable - even such a simple question as “well, what did happen if common descent is not true” pushes a sensitive button about religion and science, and about the two meanings of theory.

So I think that if anti-evolutionists are going to ask us to “teach other theories” or even present “alternative theories,” then they need to provide positive statements and positive evidence for what they think those alternatives are.

The second idea that supported my point in this discussion with Jerry was the idea that in fact for 150 years or more, scientists had been considering the hypotheses associated with special creation and common descent. Evidence in support for common descent, while not perfectly complete (sure, there are “holes” in every theory), has accumulated to the point that the vast majority of scientists consider it a well supported theory, but evidence for special creation has been lacking. Science has been open-minded about “other theories,” but science also eventually makes judgments, and special creation has been rejected when compared to the alternative of common descent.