Here’s a great example of when you should understand what you’re criticizing before you criticize it. William Dembski, one of the leading proponents of Intelligent Design recently left a post on his blog, Uncommon Descent, where he makes two arguments that vestigial structures in organisms are better evidence for design than evolution. Yes, you read that right. Dembski thinks that evolution would never have vestigial structures. Here’s his first argument:
Vestigial structures in biology are commonly cited as evidence for evolution, and it may well be that they did evolve. But if it is evidence of evolution, it is evolution in the wrong direction — it’s not the sort of function enhancing/innovating evolution that is supposed to give evolutionary theory its bite. Vestigial structures, after all, are structures that have lost their function. If all of evolution proceeded in this fashion, we’d quickly descend to a world of nonfunctionality.
Like most creationists, Dembski obviously thinks that evolution must have a set order of progression, hence his insistence on “direction”. Of course, he believes that a god directs everything in existence, so it’s not hard to see why he can’t escape the paradigm that everything must have a set path. However, the theory of evolution does not say that there is an inevitable progression of speciation. In fact, it says the exact opposite. Species will either survive or they won’t, depending on how well they are equipped to deal with the environment. This simply favors those that can reproduce enough to survive, and it means that the slightest environmental change early on could completely alter the outcome down the line. If evolution were to start over, life would certainly progress much differently and would be quite alien to anything we know today.
Additionally, Dembski refuses to acknowledge the fact that new features can arise through adoption. This undoubtedly comes from his belief that natural processes cannot add information to DNA, which relies on his rather dubious interpretation of information theory (for more, read here). I won’t go into this much further, but the idea that new features cannot arise comes from Dembski’s own hypothesis rather than the actual theory of evolution, creating yet another mischaracterization of the theory.
A great example of vestigial structures along side new ones can be seen in whales. Most modern whales have the remnants of hind legs. In the picture below, you can see the vestigial hind limbs of a humpback whale. The tiny bones hanging below the vertebra are the remnants of femurs (picture courtesy of http://www.edwardtbabinski.us/).
However, with Dembski’s version of evolution, that means all whales must have lost their hind limbs and should be stuck with nothing more than a pointed tail for swimming. However, this is not the case. As whales evolved, the tips of their tails flattened. Initially this probably helped with steering, but eventually the flukes became more efficient at providing propulsion than the hind limbs. As a result, whales’ hind limbs began to shrink since they became more of a hindrance than a help, and today whales have no externally visible hind limbs, if any at all.
As you can see, just because some structures disappear due to evolution does not mean that the same process cannot alter existing structures to the point where they become something new and more useful like the flukes on the tails of whales.
For more on whale evolution, click here.
Dembski’s second argument highlights Intelligent Design’s complete inability to usefully explain anything:
But vestigiality need not evolve by purely material means — it can also be designed. I was delighted to be informed (after my recent debate with Michael Shermer at
) of a nifty example of vestigial structures that arise not through “devolution” but rather through design, to wit, vestigial running boards on older automobiles. Bridgewater College
He then shows a series pictures with old Fords that portrays a progression from useful running boards to small fairings in later models where running boards would normally go.
This brings us to an important question: why would an intelligent designer keep these vestigial features? Does he find them aesthetically pleasing? I guess Dembski’s god must find something interesting in whales with tiny, useless bones in their tails. Of course, Dembski can’t tell us why. I’m sure he’d say we can’t understand the Intelligent Designer’s (read: God’s) reasons. And that brings us to the ultimate problem with ID. It creates more problems than it solves and then declares the new problems unsolvable. This is not how science is supposed to work. It’s supposed to help us better explain the world, not fill it with more unknowns. Just saying “God did it,” is nothing more than a copout. With Dembski’s reasoning, we might as well shut down all scientific research and return to the Middle Ages because God does everything and we can’t understand it.
Now, I’m certainly not an expert in biology, but Dembski, as a leading advocate for a biological origins theory (however unscientific it might be), shows a remarkable degree of ignorance towards modern biology. Obviously, he would never accept the prevailing views on modern biology since evolution forms its foundation, but he should at least understand the theory if he seriously wants to challenge it. Clearly, Dembski hasn’t bothered to actually learn about evolution, or he wouldn’t have made such ridiculous arguments about vestigial structures or insist that evolution has a direction. This just shows why he can’t be taken seriously. A true scientific innovator would understand the prevailing theories, not completely ignore them. Clearly, Dembski either needs to do a bit more reading or stick to math.