Book review: Of Pandas and People, Part II of II
by Percival Davis and Dean H. Kenyon
“Intelligent Design” theory (ID) proposes that life on earth came about through design by an intelligent being. Proponents seek to highlight problems with traditional evolutionary theory, and instead point to evidence that looks like life was designed. Yesterday here on my blog, I highlighted a bit of history for Of Pandas and People, and how it became an important textbook for the theory, mired deeply in an emotional and legal battle between science teachers and the Christian parents of high-school-age children.
ID doesn’t imply a young earth (though some ID theorists do think the earth is 10,000 years old or less). It simply insists that somebody made all this on purpose. Many species came into being, and then perhaps went extinct, over the last four billion years. Somebody, IDers propose, had their hand in the process the whole while, creating new species here and there over time. In order to argue the point, Davis and Kenyon examine the evidence from six different directions:
- Theories about the origin of life
- How new species supposedly evolve
- Whether the fossil record supports evolution
- Biochemical similarities
IDers don’t deny microevolution. It’s hard to deny what has been reproduced in laboratories. Since the arrival of genetics, a field of study which examines the molecular structure of genes, there is no longer any question about microevolution. That is, minor mutations occur within a species, sometimes self-correcting in later generations. But Davis and Kenyon maintain that macroevolution—creation of an entirely new species—remains statistically improbable. (I think the statistical examples given assume that random mutations all occur within the same individual, but even overlooking this assumption, the improbability still looks daunting.)
The problem is, the evidence says it happens, even if we don’t yet comprehend all the details! We might, for example, examine the 24 chromosome pairs of chimpanzees and wonder how scientists can imagine that we lost one when mankind branched off from other primates. Humans only have 23. Well, we did wonder, until we discovered precisely the two that merged into one, and traced exactly where they merged. Our chromosome 2 is a perfect match for the combined chromosomes 12 and 13 of a chimpanzee. Whether or not the idea of mankind sharing a common ancestor with other primates is distasteful, the evidence says it is so.
Thus, Davis and Kenyon have an uphill battle to fight, and some of their conclusions appear on shaky ground. There are many arguments in the book which are violently opposed by mainstream scientists, but at least two problems are so obvious that I should think any high school student of biology would immediately recognize them. One is during the discussion of whether fossils support ID or evolution. The difficulty for evolutionists is that there is an abundance of available fossils, but a relatively small proportion show a transitory state between species. The transitory record is not voluminous enough to be smooth. If, as Darwin supposed, organisms gradually evolve from one to the next, why does the fossil record have so many missing links?
So if evolution is true, it turns out not to be smooth, but “jumpy,” with transitions occurring relatively quickly (within tens of thousands of years, instead of millions). Evolutionists have differing theories about why this is so, generally assuming that accelerated transition occurs during periods of reproductive isolation. One way or another, a species is split by a barrier, and adaption to a new climate or circumstance requires rapid development in a small group, aided by in-breeding. This would account for “jumpy” evolution and the relative scarcity of transitional fossils. But to imply that the fossil record does not support evolution is simply incorrect, and any high school biology student should be aware of this. Fossil examples of transition between species are known, they are located in time and place precisely where they would be expected, and they seem to be no more rare than would be expected. We are filling many of the gaps in the fossil record, having found transitions leading from fish to amphibian, amphibian to reptile, and from reptile to birds and mammals. Of course, this can never wholly satisfy ID proponents, because when an apparent connection is found, such as the Archaeopteryx (a half-reptile, half-bird from about 150 million years ago) it is simply hailed as one more place where a creator may have designed a new “species.” Though I can’t for the life of me figure out why God would have done that on purpose.
Yeah, I said God. Let’s quit hiding behind the obvious agenda; the designer is presumed to be the Christian God. This becomes a little problematic in places, for it is hard for IDers to admit God made a few mistakes along the way. “Every species has been given an optimal body form which maximizes its function in a particular habitat.” With this assumption it becomes necessary, for example, to deny that man has the useless remnants of a tail in his skeletal structure. Instead, IDers argue that the Coccyx at the base of man’s spine is a logical design, with a completely different function than a tail; it serves as a point of attachment for muscles of the pelvic floor.
Can we really explain away this sort of oddity as Design? And if so—if we humans are already perfect—why are we made such that our genome continues to duplicate (a process called recombination) from generation to generation? Doesn’t this result in needless genetic disorders and susceptibility to diseases? Recombination seems like a pretty sloppy design if any resulting mutation is always for the worse. However, the duplication process (resulting in extra copies of genes) sure is handy for evolution! While one copy plugs along as usual, the other copy is free to mutate and take on new functions. If God felt he was designing a perfect being, duplication turns out to be a big mistake. But if God wanted to set the process of evolution in motion, He found an absolutely brilliant solution.
The other error which should be obvious to high school biology students is a rather embarrassing discussion in the book about similarities in molecular structures. The authors arrange a series of animals in a diagram on page 140, progressing from dogfish to carp to turtle to penguin to chicken to rabbit to horse. Then they wonder why, if evolution progressed as proposed, each of these animals today appear molecularly to be equidistant (measuring in terms of deviation of the cytochrome c molecule) from the starting point: the dogfish. “It has been found that organisms cannot be lined up in a series A->B->C, where A is an ancestor of B and B an ancestor of C, but are instead, approximately equidistant from most other organisms in a different taxon.” The error in thinking is obvious, of course; they are not comparing to the earliest form of the species, but to today’s carp/turtle/etc., which continued to evolve after the split. “Equidistance” should come as no surprise.
On the other hand, Pandas does present some intriguing questions, and is engaging! I thoroughly enjoyed reading it. I admit I have a hard time classifying their approach as science, when the journey stops short, preferring a more palatable solution to common descent. Throwing up one’s hands and saying “God did it” only stunts science, so I should think IDers are further compelled, if they wish to work under the umbrella of science, to investigate how an intelligent being did it. Did he sculpt new animals in the sky and gently lower them to earth? Does He have a wireless connection to a computer in heaven where He tweaks DNA during birth to create one species from another? Whatever you imagine, we are left with a category of religion, not science.
So, why do I award this book three stars, when it is skimpy science, contains more than its share of mistakes, and has an unsubtle agenda? Well, it’s not just that the book is informative and easy to read. It’s that I dearly wish I had had such texts when I was in high school! Teaching students to question, to engage in the rough-and-tumble world of scientific exploration, is how young curiosities are piqued. So long as the book is accompanied by more standard evolutionary texts, and so long as the teacher is knowledgeable about the topics and can discuss the arguments fairly, I think the question of Intelligent Design has a place. If ID fails (at least, a version of ID as involved as this book), then as a high school student I really would have liked to know why, and how, by addressing an important topic head-on. Students deserve answers.