A student in David Barash’s animal-behavior class at the University of Washington might feel a bit like David facing Goliath — even though Goliath, in this case, happens to be named David. Goliath occupies the podium at the front of the class, holds the professorship, and has the authority of the scientific community (apparently, anyway) on his side.
To keep things civil, let’s identify Goliath not with David Barash himself, but with the neo-Darwinian theory of evolution. Barash delivers "The Talk" on behalf of the power of neo-Darwinism, and the Talk brings bad news for theists, on three fronts:
There’s no evidence for intelligent design in biology, because random variation and natural selection — an entirely mechanical, undirected process — can do the designing. Thus there are no evidential grounds for believing in a creator of life or biological complexity.
There’s nothing special about you or any other human being. You’re an animal like every other animal. Deal with it.
There’s no solving the problem of natural evil. "The more we know of evolution," says Barash, "the more unavoidable is the conclusion that living things, including human beings, are produced by a natural, totally amoral process, with no indication of a benevolent, controlling creator."
Now, it’s been a while since I was an undergraduate studying evolutionary biology (1980-84), but I had self-professed atheist professors like Barash. Their confidence and knowledge were intimidating.
But I also had mentors cut from very different cloth, such as National Academy of Sciences theoretical physicist Robert Griffiths. When I became discouraged, I would walk across Schenley Bridge from the Pitt campus to Carnegie-Mellon, into Bob’s office, where he would encourage me not to be fearful. Work hard to understand the arguments against your own position, he would say, and inevitably, you’ll find the weaknesses in those arguments.
So, in the spirit of Bob Griffiths’s advice to me, I offer the following suggestions to any students dealing with their own academic Goliaths.
First, no aggression. David slaying Goliath is a justly famous account of bravery, but that was a literal battlefield. Your task is to persuade, not harm. Your sling and stones should be the evidence — or its conspicuous absence.
Which brings me to Barash’s first and really only significant claim, namely, that "random variation plus natural selection, contains all that is needed to generate extraordinary levels of non-randomness." No intelligent designer need apply: an "entirely natural and undirected process" will do the work of building organisms, including human beings.
Okay — if this claim is true, we should be able to find in the scientific literature the detailed explanations for the origin of complex structures and behaviors, rendered strictly in terms of random variation plus natural selection.
Guess what? Those explanations aren’t there; they don’t exist. If anyone doubts this, he should try looking for himself. Choose any complex structure or behavior, and look in the biological literature for the step-by-step causal account where the origin of that structure (that is, its coming-to-be where it did not exist before) is explained via random variation and natural selection.
You’ll be looking a long time. The explanations just aren’t there, and this fact is well known to evolutionary biologists who have become disenchanted with received neo-Darwinian theory. When proponents of the received theory, such as Richard Dawkins, face the task of making random variation and natural selection work, they resort to fictional entities like Dawkins’s "biomorphs" — see Chapter 3 of The Blind Watchmaker (1986) — or flawed analogies such as the "methinks it is like a weasel" search algorithm scenario. No one would have to employ these toy stories, of course, if evidence were available showing the efficacy of random variation and selection to construct novel complexity.
"Research on selection and adaptation," notes Mary Jane West-Eberhard, a disenchanted evolutionary theorist, "may tell us why a trait persisted and spread, but it will not tell us where a trait came from….This transformational aspect of evolutionary change has been oddly neglected in modern evolutionary biology" (2003, p. 197). Typically, when a disappointed biologist such as West-Eberhard departs in search of a better theory of evolution, her point of leaving is dismay at the explanatory poverty of what neo-Darwinism has delivered over the past several decades. The theory promised big, delivered tiny.
According to Jerry Coyne (2009, p. 138), however, showing the details is not the job of evolutionary biologists:
In such cases the onus is not on evolutionary biologists to sketch out a precise step-by-step scenario documenting exactly how a complex character evolved. That would require knowing everything about what happened when we were not around — an impossibility for most traits and for nearly all biochemical pathways.
If that’s so, then how do we know that random variation and natural selection were actually sufficient? "Feasibility," answers Coyne, and by that generous standard, "we know of no adaptations whose origin could not have involved natural selection" (2009, p. 138). After all, writes Coyne a few pages earlier (p. 136), "we know of no other natural process that can build a complex adaptation."
Feasibility can be purchased on the cheap, however. Heck, you can manufacture it yourself, given a trace of storytelling ability. Once one gets the hang of it, inventing the variations one needs and some sort of selective pressure to increase the frequency of (and fix) those variations in unobserved populations becomes a speculative exercise with no connection to biological reality. And saying that natural selection is the only game in town, particularly when one has excluded intelligent design a priori, does not allow us to credit selection with genuinely explaining the origin of complexity. The devil is in the details.
Random variation and natural selection aren’t the only game in town, of course, as the growth of the ID community over the past twenty years has demonstrated. If Barash’s claims about the sufficiency of neo-Darwinian theory fail, his assertions about "indistinguishable" humanity and our bleakly amoral origins will tumble as well. Once the big guy — the Goliath theory — goes down, the lesser claims follow.
Barash considers himself free to attack the worldviews of his students. Fair enough: do they have the freedom to raise questions about his favorite theory? Science is as science does: a strong theory, well supported by evidence, needs to fear no questions. A weak theory supported by bluster, on the other hand — that theory should worry about a stone coming hard from a fast-whirling sling.
Coyne, Jerry. 2009. Why Evolution Is True. New York: Viking.
Dawkins, Richard. 1986. The Blind Watchmaker. New York: W.W. Norton.
West-Eberhard, Mary Jane. 2003. Developmental Plasticity and Evolution. Oxford: Oxford University Press.