Bad Cop

I occasionally find myself in awkward situations.

The Truth Project is a set of 12 DVD-based video lessons produced by Focus on the Family, a well-known evangelical Christian organization. Each lesson is roughly one hour long and takes the form of a lecture given by Dr. Del Tackett, former president of the Focus on the Family Institute. Lessons are always based on a specific theme; for example, the first three lessons are "Veritology: What is Truth?", "Philosophy and Ethics: Says Who?" and "Anthropology: Who is Man?"

The DVDs are meant to be viewed in small groups and discussed afterwards. The series is quite obviously intended for an evangelical Christian audience, which makes my own participation in one these discussion groups a little unusual. I have a number of Christian friends who I hang out with fairly regularly and a while back I was invited to attend their viewings of The Truth Project. I've gone every time since then and usually have very little to say. The lessons are presented such that it's difficult to have the sorts of desired discussions about them unless you share the beliefs. The questions posed are generally ones that you can only constructively answer if you already assume the Christian God exists. Pretty much the only time I feel qualified to join in is if Tackett spends a lot of time dissing the views of the secular world and his comments spill over into the following discussion. Luckily, Dr. Tackett's had a lot to say about the secular world lately.

I knew Lesson 5 ("Science: What is True?") was going to be interesting as soon as I saw the preview. As the title suggests, the lesson is largely about contemporary science, with a special focus on (what else?) Darwinism. This topic is apparently troubling enough to warrant extra time, and the lesson is thus divided into two parts. Part One is more general, lamenting modern science's refusal to consider what might exist outside "the box" (i.e. the material universe). Towards the end, Tackett turns specifically to Charles Darwin and his ideas of evolution, which segues neatly into Part Two: a full blown attack on evolutionary theory. This post is my response to Lesson 5 of The Truth project, especially Part Two.

First things first: I'm not a biologist. In fact, even if there are infinitely many versions of me, each living in one of an infinite number of universes, none of them are biologists either. But I have done some reading on the subject of evolution and I'm familiar with a lot of the basics. I write this response partly to test my own knowledge of the topic and partly as cathartic rant. I'd also like to think it'll help Truth Project viewers identify some of the possible shortfalls of this whole endeavor, but that assumes people read my blog--and that's not an assumption I'm willing to make.

Let's start at the end of Part One.

Dr. Tackett makes much of Psalm 19's opening line: "The heavens declare the glory of God." To him, this means that God's fingerprints are all over the natural world. Evidence of God is everywhere in nature and Dr. Tackett finds it just a tad ludicrous that anyone could not see it. The beauty and intricacy of nature point unavoidably to a grand designer. He's an unabashed supporter of Intelligent Design (ID), that nebulous cluster of views that can and does include everything from Young Earth Creationism to whatever the hell David Berlinski believes. One of Dr. Tackett's frequently used tricks in this lesson is to pick quotes from various atheistic figures that apparently show the laughable extremes to which they'll go to avoid seeing God's signature in our universe. He finishes Part One by presenting Darwin's often quoted statement on the peacock's tail: "It is curious that I remember well a time when the thought of the eye made me cold all over, but I have got over this stage of the complaint, & now small trifling particulars of structure often make me very uncomfortable. The sight of a feather in a peacock's tail, whenever I gaze at it, makes me sick!" The reason the peacock's tail made Darwin so sick, Dr. Tackett concludes, is that it's simply too beautiful to have come about by blind natural processes. The unconscious forces of a strictly material universe could not possibly have been responsible for something so breath-taking. Dr. Tackett thus ends as he began, proclaiming once more that "the heavens declare the glory of God."

It's a performance as effective as it is deceptive (I apologize for the Jesse Jacksonism). While those unfamiliar with Darwin's life and work were likely sold on Dr. Tackett's use of this quote, one need only access Wikipedia to see the problem with it. The peacock's tail did not make Darwin sick because it's profoundly beautiful, but because it's profoundly cumbersome. It's big, heavy, and makes flight harder than it needs to be. Natural selection is supposed to be a process by which organisms become better equipped to survive in their environments, so how could it explain something like the peacock's tail, which is so clearly a hindrance to the peacock's survival?

The answer was sexual selection, a specific kind of natural selection. Darwin had introduced a shareware version of this idea in The Origin of Species (1859) but had apparently not yet realized its full significance when he wrote the letter quoted from above (1860). By the time he published The Descent of Man in 1871, however, he was no longer sickened by the peacock's tail. By that point he had seen that although the peacock's tail is a costly burden in many cases, peahens seem to go crazy over them--the bigger and fancier the better. Sexual selection is partly responsible for differences in characteristics between the males and females of each species, and males can develop burdensome traits if the females of their species find them attractive--and so long as the decreased likelihood of long-term survival is outweighed by the increased likelihood of reproduction.

Dr. Tackett seems happily unaware of any of this, and he doesn't become any more knowledgeable in Part Two. He begins by introducing the idea of irreducible complexity. Irreducible complexity is an idea frequently invoked by ID advocates like Michael Behe and Stephen Meyer. Darwin, you see, once wrote that if ever a trait could be found that could not have evolved through a gradual series of slight yet beneficial steps, his theory would "absolutely break down." About 14 years ago, Michael Behe claimed to have found several biological systems that violated Darwin's theory in a book called Darwin's Back Box and dubbed them irreducibly complex. This basically means that these complex multi-part systems absolutely require every part to be present and accounted for to work, and if just one is removed, the whole thing ceases to function. Thus, they could not have evolved through a sequence of gradual modifications.

The most infamous of these irreducibly complex systems is the bacterial flagellum, a curious biological rotary engine that propels certain types of cells. It's a rather intricate piece of work made up of about 50 essential components (don't ask me how it works--I'm paraphrasing the Internet here). Given that it's probably the most popular example of irreducible complexity out there, Dr. Tackett flaunts it like a new nipple piercing.

The bacterial flagellum is undoubtedly complicated. But to serve as any kind of a meaningful counter-argument to Darwinian evolution, the bacterial flagellum must be complicated in such a way that removal of any of its parts would render what's left utterly useless. Does the flagellum meet this criterion?

Incidentally, I'm reminded of a joke some of our biology teachers used to kick around in high-school during lunch hour. Q: How do you get a Type III secretion system? A: By removing 40 of the bacterial flagellum's parts. It's not very funny, I know (humor was a lot dryer back in those days), but it does make a good point: the bacterial flagellum is not irreducibly complex. Systems such as the flagellum and other similarly complex structures can evolve through something called exaptation, where earlier structures that served other functions can be shaped into new structures with new functions. The bacterial flagellum appears to be an example of this. It may indeed need all of its parts to function, but that doesn't mean it couldn't have evolved from predecessors that had other uses.

Biologists have been making this point for years. Those like Behe typically respond by reiterating that while, yes, you can remove parts of the flagellum and be left with other structures, these other structures do not serve the same function as the bacterial flagellum. The appropriate response to this is "so what?" Evolutionary theory requires only that a given feature be able to, in principle, evolve through a step-by-step process, not that every stage of that feature's evolution serve the exact same function. Irreducible complexity is thus worthless as an argument against Darwinian evolution.

Fortunately, Tackett brings more than just irreducible complexity to the party. He goes on to discuss the fossil record, making the bizarre statement that even though we have more fossils than we did in Darwin's time, the fossil record is now less complete. I suppose he could mean that the new fossils we've gathered since then raise more questions than they answer, but that's wrong. The transition between fish and the first land-treading amphibians is well documented, as is the evolution of whales from land-dwelling mammals, and others. Yes, the fossil record is less complete than we'd like, but this is inevitable given the numerous conditions that must be fulfilled before a fossil can be formed and discovered. Tackett plays a video clip featuring David Berlinski, who seems to think that if there are 50,000 transitional forms between species A and species B, we need all 50,000 of these forms represented in the fossil record before we can accept that evolution took place. This is neither expected nor required.

While discussing the fossil record, Dr. Tackett also takes the time to get Stephen Jay Gould's (and Niles Elredge's, though he isn't mentioned) theory of punctuated equilibrium wrong. He presents it as a desperate attempt by an atheistic scientist to explain the gaps of the fossil record without invoking special creation. Tackett describes punctuated equilibrium as the theory that species undergo lengthy periods of evolutionary stability (meaning very little change) followed by brief periods of rapid change, followed again by more stability with occasional rapid change. He contrasts this with the view that species change very gradually over time. He visually represents the later as a diagonal line and the former as a staircase.

This is vaguely accurate, but as with many other ideas he discusses, both in Lesson 5 and elsewhere, Tackett leaves out important details. First of all, those periods of "rapid" change are rapid only by the standards of geological time. I believe Gould estimated them to be roughly 50,000 years long. They are not instantaneous, as the straight vertical lines that Tackett uses to visualize them would seem to suggest. Punctuated equilibrium emphasizes the importance of evolutionary pressure. When a population becomes adapted to an environment they tend to stay that way, assuming no drastic environmental changes occur. As the annoying cliché goes: if it ain't broke, don't fix it. But when a segment of a population breaks off and wanders into new territory, there will be added pressure on those bold pioneers to adapt to their new environment, which leads to the relatively quick emergence of new species.

Punctuated equilibrium was controversial with a lot of biologists after it was introduced and in the following decades. Oddly enough, one of the reasons it was so controversial is actually because it's such a non-controversial idea. It was presented by journalists in the media (and by creationists) as a violent overthrow of Darwinist orthodoxy when, in reality, it was more of a playful nudge. In fact, the first time I actually read about punctuated equilibrium in an essay by Niles Eldredge I was surprised at how closely it conformed to what I had already understood evolutionary theory to be. Modern Darwinism is happy to admit that species to not evolve at a constant rate (even Darwin himself admitted this). Species go through relatively little change when there is no reason for it, and relatively large change when the environmental pressures are there. Even if Eldredge and Gould underestimated the amount of time it takes for speciation to occur (more recent estimations put it between 100,000 and 5 million years), the basic ideas of punctuated equilibrium do not conflict with Neo-Darwinism in any meaningful way.

And since we're on the subject of speciation, Tackett saves some of his weakest criticism for the idea of macroevolution. Many creationists will concede that microevolution--slight changes within otherwise fixed species--is a reality, but that macroevolution--big changes that include the formation of entirely new species--is impossible. To illustrate this Tackett shows a clip from what appears to be a documentary sympathetic to ID. Several ID advocates, including Berlinski, discuss modern day observations of the Galapagos finches, the same species that Darwin himself studied. The speakers describe a drought on the Galapagos Islands that results in an increase in the average beak size of a species of finch. At first this appears to be cause for concern; but it is then revealed, to everyone's relief, that eventually, after several more generations, the beak sizes come back down. They conclude from this that significant evolutionary changes are impossible and Darwin was wrong.

There are several problems here. First, the Galapagos finches in this story are indeed not an example of speciation, but no one has claimed that they are (in fact, Tackett and the speakers in this clip are the only ones I've heard discuss these finches in terms of speciation). What the Galapagos finches are is an excellent example of natural selection. You could be forgiven for not realizing this, as the ID advocates in the video clip are predictably stingy with the details. The reason beak sizes increase during the drought is that the small seeds produced by herbs and grasses become scarce. Under these conditions, the finches are forced to turn to large seeds for food. But finches with smaller beaks have trouble breaking these larger seeds, so finches with larger beaks gain an advantage and natural selection promotes an overall increase in beak size in subsequent generations.

So why does the average beak size then come back down? Because the drought ends. When things return to normal, small seeds become more abundant and smaller beaks regain their advantage. The Galapagos Islands go through these periods of drought every so often, resulting in changes to the environment which in turn leads to changes in the physical features of the island's inhabitants, exactly as Darwinism predicts. It's not speciation (remember, speciation usually takes between 100,000 and 5 million years), but again, no one said it was. So in attempting to discredit macroevolution, Dr. Tackett and company end up supporting natural selection, even if they don't realize it.

But still, what about macroevolution? If we don't see it among Darwin's finches, where do we see it? While the fossil record would be one obvious place to look, there are other options available for those who want something a little more dramatic. Had Tackett been genuinely interested in trying to debunk macroevolution, he could have gone after one of the many examples of observed speciation that have occurred within the span of a human lifetime. New species of flowering plants, for example, are known to occasionally arise through an event called polyploidy. One way this can occur is when two species of plants living in the same area produce a hybrid species that has all of its chromosomes doubled. The resulting hybrid will be unable to interbreed with either parent species, but it will be able to produce members of its own (brand new) species.

He could have done this, but honestly, it's hard to believe after watching Lesson 5 that Dr. Tackett has any interest in seriously engaging modern evolutionary theory, or any other idea he takes issue with. He treats the stunningly clueless video about the Galapagos finches as a definitive refutation of Darwinism, as if that was the only piece of evidence the evolutionists have. He declares during the course of this lesson that "Darwin's theory is absolutely breaking down," gleefully ignorant not only of the crippling flaws in his own arguments, but of the vast body of evidence in favor of evolution that he hasn't even begun to acknowledge, such as sequence alignment, phylogenetic reconstruction, atavisms and pseudogenes, evolutionary developmental biology, biogeography, comparative anatomy, and so on.

Obviously, not everything has been worked out. There will always be gaps in evolutionary theory. It's doubtful that any scientific theory will reach a state of perfect completion. But fortunately, that isn't necessary. What we do have is more than enough to establish the reality of common descent.

At the very least, you can say it's a better explanation than anything Tackett is likely to muster, not that he tries and not that I would expect him to. Intelligent design, after all, is not so much a coherent alternative to Darwinian evolution as a vague and constantly shifting gun tower from which stubborn biblical literalists and contrarian philosophers can take potshots at mainstream evolutionary science. It exists not to further our understanding of how the world works, but to open an escape hatch for those wishing to dodge the implications of evolutionary theory. It's a tiny escape hatch, yes, but anyone who wants badly enough to squeeze through it will undoubtedly find a way to do so (to be fair, everyone, atheists included, rejects positions they don't like based on flimsy reasoning--that's just the way human beings roll).

I'll discuss whether or not Christians really need to be afraid of evolutionary theory next time. For now, I'll say once again that Tackett is wrong on virtually every count, and I'd urge anyone who genuinely wishes to understand evolutionary theory to read the works of those who have contributed to it. Read them in their original context, not filtered through the bias of their ideological enemies. I wouldn't trust an evangelical atheist to accurately present the views of a Christian theologian. When I want to find out what Christians think, I watch, read, and talk to Christians. Likewise, no Christian should trust an evangelical creationist to present an accurate view of evolutionary theory. And indeed, Dr. Tackett does not accurately describe what evolutionary biologists think.

Nor, for that matter, does Tackett accurately present the opinions of anyone who doesn't share his beliefs. This is a major problem with The Truth Project as a whole. Every time he speaks on non-fundamentalist views that I'm even vaguely familiar with, Tackett reveals an unsettling ignorance, either distorting his opponents' positions or leaving out important details. While discussing Julius Wellhausen's documentary hypothesis and the views of the Jesus Seminar, for example, he neglects to mention the reasons why these people came to their conclusions in the first place. It's taken for granted that they're wrong simply because they disagree with Tackett's own conclusions. He also builds a vast atheistic straw man by stringing together bite-sized quotes from a huge variety of diverse sources, presenting each one as a thought emitting from a single colossal secular overmind. Each carefully mined sentence, it is assumed, is an official position statement from the secular world at large.

Much of The Truth Project's effectiveness depends on this sort of manipulation. A drastically oversimplified summary of Abraham Maslow's hierarchy of human needs reveals the secular world to believe that human beings are inherently good. Tackett then shows a montage of disturbing scenes culled from international news footage that shows humanity at its worst, suggesting on a deeply visceral level that our species is utterly depraved. Next comes a shot of Tackett's studio audience, visibly unnerved, the occasional tear streaming down a quivering cheek. It's a dramatic, well-staged segment that skillfully drives home its point: only a fool would say human beings are inherently good.

Never mind that scientists and others involved in the relevant areas of research have rejected the "inherently good" view of human nature for at least half a century. The gene-centered view of natural selection, along with the fields of sociobiology and evolutionary psychology have revealed a pervasive selfishness to human nature that would warm Tackett's heart were he not stubbornly committed to ignoring these things. Of course, they also reveal inherent tendencies towards compassion, empathy, and cooperation. The point is that human nature is a complicated thing, neither wholly good nor evil, and while you can still find many who assume the naïvely sunny view that Tackett mocks, others have embraced the messier and more realistic portrait of our species. There is no overmind.

That Tackett is able to make his worldview appealing only by distorting the alternatives is a serious problem for his particular strand of Christianity. Tackett demonstrates repeatedly throughout this series that he is simply incapable of honestly confronting his chosen opponents. True, some of the misrepresentations might be the products of honest mistakes; but others, such as the treatment of Darwin's comments on the peacock's tail and nearly everything that follows, could only be the results of extreme scholarly laziness or intentional dishonesty. Neither says much for the integrity of The Truth Project.

I'll have nicer things to say in my next post.