Review: Darwin Strikes Back
Work under Review
In Darwin Strikes Back, Thomas Woodward presents himself as an arbiter between evolution and “intelligent design” (ID). His verdict is that scientists have responded to ID with heat and venom, but have not effectively refuted ID claims.
There are three general types of difficulty with Woodward’s book:
- He presents an inaccurate and caricatured version of evolutionists’ arguments.
- He does not reference the most scholarly refutations of ID arguments, but focuses instead on short book reviews and popular- level articles.
- When he discusses the scientific details, he routinely gets important things wrong.
Chapter five discusses Michael Behe’s notion of “irreducible complexity.” Behe argued that many biological systems were such that if any of their parts were removed the resulting system would cease to function. It followed, Behe claimed, that they could not have evolved gradually by natural selection.
Scientists offered two main replies. First, Behe’s logic was simply wrong. That every part is needed in the present does not imply that the system could not have formed gradually. You can see the basic principle in everyday life. Desktop computers are absolutely indispensable today. But in the 1970s and early 80s they were a luxury. Their indispensability evolved gradually over time. Likewise in biology. You could have a part in a system that was not essential when it first appeared, but became essential after further evolutionary changes. This is one of several possibilities.
So the first line of response to Behe was to point out that there are a variety of well-known, observable biological mechanisms through which a supposedly irreducibly complex system could have evolved gradually. Since Behe was the one making grand claims about what was possible and what was not, it was for him to explain why these scenarios, which were drawn from actual scientific research, were impractical.
The second line was to point to specific biochemical systems, some of Behe’s favorites among them, and refer to professional research explaining how they evolved. There is a huge literature on blood clotting evolution, or immune system evolution, or eye evolution, to pick a few famous examples. So it is not just that evolution can, in principle, explain complex systems (though that alone would be enough to refute Behe), it is that evolution has done so repeatedly in practice.
Woodward tells a different story. He lists three different approaches he claims scientists have taken towards Behe’s argument. First, he claims, they merely attacked Behe’s analogy of a mousetrap for illustrating irreducible complexity, rather than the concept itself. It is true that scientists have (rightly) pointed out that Behe’s analogy is inapt, but this is hardly the main line of criticism.
Second, Woodward says that scientists have resorted to the “unexplained does not mean unexplainable” defense. Once again, scientists do (rightly) make this point. Certainly there are plenty of complex systems with murky origins. But there are many others that have been so explained, and that is enough to show that there is no fundamental problem here for evolution.
It is only in the third part of his chapter that Woodward moves away from straw men and mentions some of the main arguments raised against Behe. However, he does a thoroughly inept job of it. He gives no clear explanation of the anti-Behe arguments, basing himself almost entirely on popular-level writing. Reading a few book reviews or exchanges on the internet is not adequate.
Woodward also devotes a chapter to Jonathan Wells’s book Icons of Evolution (Washington [DC]: Regnery, 1999). Wells claimed that many of the standard textbook examples of evolution were false or misleading and chose ten examples to make his case. Scientists responded in the most direct way possible. They showed at length that in every case it was Wells’s version of things that was wildly inaccurate and that any charges of fraud were far more plausibly leveled at him than at scientists.
Woodward again ignores the serious, lengthy refutations written by professionals, instead relying almost entirely on short book reviews that appeared in popular-level venues. And when Woodward does discuss actual science, he usually gets it wrong. For example, on pages 103–4 of his book, Woodward discusses the Cambrian explosion. As Woodward tells the story, the critters we find in the Cambrian rocks (among the oldest rocks containing animal fossils) show phylum-level differences. Modern organisms placed in different phyla show profound anatomical differences. Humans, oysters, and spiders are all in different phyla.
In stressing these phylum-level differences, Woodward implies that the animals found in the Cambrian fossils were as wildly different from each other as, say, humans and spiders are today. If this were true, it would be a serious problem for evolutionists.
Sadly, Woodward has simply garbled a fairly basic point of taxonomy. Phyla are classifications used for modern organisms. Applying them retroactively to long-extinct creatures is problematic. When paleontologists place Cambrian fossil X in one phylum and Cambrian fossil Y in a different phylum, they are not saying that X and Y are as different from one another as humans and spiders (for example) are today. They are saying simply that X shows some feature that in modern organisms is associated with one phylum while Y shows some feature that is today associated with a different phylum.
The Cambrian explosion is a problem for evolutionists only in the sense that there are many possible explanations for it, but too little data for coming to a firm conclusion. Woodward shows little awareness of the actual state of scientific play.
This is merely a taste of all that is wrong with this book. Woodward makes much of the fact that scientists use strong rhetoric in denouncing the arguments of ID folks. Of course they do. Woodward and his ilk run around the country accusing scientists of the crassest sort of ignorance and incompetence. The ID literature asserts that the common wisdom in every branch of the life sciences, whether in genetics, evolution, paleontology, anatomy, biochemistry and so on, is simply wrong. People study for years to become experts in any one of these disciplines, and then they have to put up with people bearing obvious religious and political agendas completely distorting everything about their subject. Is it surprising that they respond with anger?
Department of Mathematics and Statistics
James Madison University
Harrisonburg VA 22807
Jason Rosenhouse is Associate Professor of Mathematics at James Madison University. He offers commentary on the endless dispute between evolution and creationism on his blog at www.scienceblogs.com/evolutionblog/.