Dembski vs. Evo Devo

William Dembski exemplifies the empty void of Intelligent Design creationism in his criticisms of Michael Ruse's review of Sean Carroll's Endless Forms Most Beautiful: The New Science of Evo Devo and the Making of the Animal Kingdom. Ruse's review was positive (as was mine—it's an excellent introduction to the discipline), but he takes a jab at the creationists at the beginning:

A major problem with the critics of science is that they have a problem with problems.

Let me be a little less cryptic. The critics—notably the creationists, and more recently their smoother descendents, the intelligent design theorists—are always whining that science has unfinished or unsolved problems.

This did not sit well with Dembski, who goes on to write a complaint that demonstrates that Ruse was exactly right in every particular, and also demonstrates several other creationist traits, such as an inability to read with understanding and quote mining.

In his review of Endless Forms Most Beautiful, Sean Carroll's new book on evo devo, Michael Ruse faults intelligent design (ID) for harping on evolution's unsolved problems. Moreover, Carroll as well as Ruse suggest that evo devo has now resolved one of the major problems on which design theorists have been harping.

Go ahead—read Ruse's review or Carroll's book. There is no blanket claim of a complete solution of anything, and Dembski is making stuff up. Instead, you will find that what we've got is a productive strategy for addressing evolutionary problems.

Wrong on both counts. Intelligent design does not have a problem with problems. It has a problem with bogus solutions that Darwinists like Ruse and Carroll dress up as real solutions to the problems of biological origins.

Note that while he's claiming he doesn't have a problem with problems, there is one figure in the article of developing squid (and truth be told, that tease was the only reason I read Dembski's article) with the question, "Can evo devo explain squid evolution?". To my disappointment, that's all he says about it—he raises the question, as if that is enough to indict evo-devo, and he certainly does not offer a research program of any kind.

The answer to the question, of course, is yes. Evo devo is not a collection of answers, but a set of approaches and principles that help us tackle difficult problems like the evolution of squid. It says that if we want to understand how organisms evolve, we need to understand the mechanisms by which genetic information is translated into form and function…the process of development. It's awfully hard to disagree with that, but Dembski tries. Or rather, he seems to think that bringing up unsolved problems in squid evolution is enough to show that evo devo has failed.

Look, if we want to understand how modern animals evolved from older forms, we should try to understand:

  • How genes produces morphology.
  • The genetics underlying large scale differences in form, between squid and fruit flies, for instance.
  • The mechanisms that generate striking morphological differences between closely related species, as we see in African cichlids.
  • The genetic basis of morphological variation within populations.

Evo devo does not declare that it has all the answers, it proudly announces that it has the right questions and a good toolkit to address them. Those are all questions that scientists are trying to answer, too; the Intelligent Design creationists don't even bother to ask interesting questions. Generalize his tantalizing opening question to "How can we explain squid evolution?". I can say how scientists would work to explain it. Dembski thinks just asking the question ends the search and does not bother to offer an Intelligent Design creationist's research strategy.

Where Dembski is at his most contemptible, though, is when he mangles the scientific literature to get an answer he wants. Here's an example of creationist quote mining:

But that raises a fundamental problem. Elizabeth Pennisi, in a report about evo devo for the journal Science, dated Nov. 1, 2002, stated the problem this way: "The lists [of conserved genes give] no insight into how, in the end, organisms with the same genes came to be so different."

Wow. That sure sounds like an admission of failure. Those scientists must be stymied.

It's a grossly misleading excerpt, however. This was taken from a report explaining how developmental biologists were excited about the promise of new strategies in evo devo, and listed several examples of successes. All you have to do is read on a few sentences further to see the way the work is going.

The lists gave no insight into how, in the end, organisms with the same genes came to be so different. And given the evolutionary distance between, say, a fruit fly and a shark, "there isn't really an experimental manipulation to let you get at what the genes are actually doing," says Rudolf Raff, an evolutionary developmental biologist at Indiana University, Bloomington (IUB).

The solution, say Jeffery and others, is to focus on genetically based developmental differences between closely related species, or even among individuals of the same species. This is the stuff of microevolutionists, who care most about how individuals vary naturally within a population and how environmental forces affect this variation.

Uh, what's that? They aren't arguing that there is no insight at all, but merely that by working on smaller differences in more closely related species, they have a better handle on how to attack the problem? Hmmm. Further, the next page of the article summarizes recent dramatic successes with this approach, such as in understanding the evolution of cavefish eyes, the nematode vulva, and butterfly eyespots, where examination of differences between closely related species has enabled us to track exactly how genetic changes have led to the differences in form.

Dembski doesn't understand how science in general works, and even after consulting his incompetent colleague, Jonathan Wells, he definitely doesn't understand developmental biology. This passage is painful in its ignorance.

To sum up, developmental geneticists have found that the genes that seem to be most important in development are remarkably similar in many different types of animals, from worms to fruit flies to mammals.

Initially, this was regarded as evidence for genetic programs controlling development. But biologists are now realizing that it actually constitutes a paradox: if genes control development, why do similar genes produce such different animals? Why does a caterpillar turn into a butterfly instead of a barracuda?

This phrase, "biologists are now realizing that it actually constitutes a paradox", is simply false. There is no paradox at all there, and it doesn't trouble us at all. If you observed surveyors at work, and noticed that they marked off two plots of land of identical size, surveyed with similar instruments, and staked out with the same tools, and then bulldozers and carpenters and bricklayers and plumbers and electricians show up at both, but then later discovered that a gas station and convenience store was built on one, while a three-bedroom ranch house was built on the other, would you announce that there was a paradox here? Of course not. You're not an idiot.

What developmental geneticists have discovered is that different organisms use remarkably similar toolkits to assemble their form, and that what matters is how those tools are deployed during development. It's the patterns of regulation and interaction between those genes, which do differ in interesting ways, is what generates differences between species. And that's why Sean Carroll can legitimately argue that evo devo is a worthwhile focus for research.