A conservative ignores Augustine

The Catholic Saint Augustine once said:

Usually, even a non-Christian knows something about the earth, the heavens, and the other elements of this world, about the motion and orbit of the stars and even their size and relative positions, about the predictable eclipses of the sun and moon, the cycles of the years and the seasons, about the kinds of animals, shrubs, stones, and so forth, and this knowledge he hold to as being certain from reason and experience. Now, it is a disgraceful and dangerous thing for an infidel to hear a Christian, presumably giving the meaning of Holy Scripture, talking nonsense on these topics; and we should take all means to prevent such an embarrassing situation... .

This point can be generalized from Catholic proselyzation to pretty much any advocacy; if you see someone talking nonsense while advocating a cause with which you agree, you should seek to stop him. Charles Krauthammer and George Will, among others, have sought to do that on behalf of modern American conservatism with regards to the political anti-science Intelligent Design movement. But Tom Bethell soldiers on with the nonsense.

George Will tells us that evolution is a fact. Is it? It depends on what you mean by evolution. Add an antibiotic to a dish of bacteria, so that some die and some survive, and bacterial resistance may be seen. This is said to illustrate natural selection — Charles Darwin's great discovery and claim to fame — and, therefore, evolution in action. Charles Krauthammer is pleased to tell us that the advocates of intelligent design "admit" that natural selection "explains such things as the development of drug resistance."

But what actually happens in the Petri dish? Some of the bacteria are naturally equipped with enzymes that give them immunity to the antibiotic. So they survive, while most of the bacteria die. Nutrients remain in the dish, and the resistant strain now has an ample food supply and multiplies. Before, it could hardly compete with the far more abundant strain, now wiped out. So the (pre-existing) resistant strain becomes more numerous. There is a multiplication of something that already existed. But as the famous geneticist Thomas Hunt Morgan said about 100 years ago — he spent years studying fruit flies at Columbia University and was rewarded with the Nobel Prize — evolution means making new things, not more of what already exists.

The problem here is that Bethell takes one example that is often used because it is easy for the layman to understand and presents it as if it were the only example. It's simply not. For one, there are experiments showing improved environmental fitness in populations taken from a single individual organism. These populations are called clonal. One of several examples from the Beneficial Mutations page of Robert Williams's Evidences for Evolution website is this (details can be found in Selection: The Mechanism of Evolution by Graham Bell):

Chlamydomonas is a unicellular green algae capable of photosynthesis in light, but also somewhat capable of growth in the dark by using acetate as a carbon source. Graham Bell cultured several clonal lines of Chlamydomonas in the dark for several hundred generations. Some of the lines grew well in the dark, but other lines were almost unable to grow at all. The poor growth lines improved throughout the course of the experiment until by 600 generations they were well adapted to growth in the dark. This experiment showed that new, beneficial mutations are capable of quickly (in hundreds of generations) adapting an organism that almost required light for survival to growth in the complete absence of light.

So here is an example of a mutation that improves fitness. Bethell might object that the original organism could use acetate to grow, so we only have a mutation which improves a pre-existing function. And yet we have moved a step beyond his original objection that "the (pre-existing) resistant strain becomes more numerous." This could not have been a pre-existing strain, since we started with one individual. But is there an example of a new function being added? Courtesy of Dave Thomas over at the New Mexicans for Science and Reason, yep.

My favorite example of a mutation producing new information involves a Japanese bacterium that suffered a frame shift mutation that just happened to allow it to metabolize nylon waste. The new enzymes are very inefficient (having only 2% of the efficiency of the regular enzymes), but do afford the bacteria a whole new ecological niche. They don't work at all on the bacterium's original food - carbohydrates. And this type of mutation has even happened more than once!

Now, as Dave Thomas mentioned later in his piece, Nylon didn't exist before 1935. And the mutation produced an enzyme that could metabolize Nylon but not the bacterium's original food source. So this mutation allowed the organism to produce an enzyme that allowed the bacterium to do something that it couldn't have needed to do before -- it introduced a new function. But what about the evolution of multicellular organisms from single cells? Yep.

[Boraas, M. E. 1983. Predator induced evolution in chemostat culture. EOS. Transactions of the American Geophysical Union. 64:1102] reported the induction of multicellularity in a strain of Chlorella pyrenoidosa (since reclassified as C. vulgaris) by predation. He was growing the unicellular green alga in the first stage of a two stage continuous culture system as for food for a flagellate predator, Ochromonas sp., that was growing in the second stage. Due to the failure of a pump, flagellates washed back into the first stage. Within five days a colonial form of the Chlorella appeared. It rapidly came to dominate the culture. The colony size ranged from 4 cells to 32 cells. Eventually it stabilized at 8 cells. This colonial form has persisted in culture for about a decade. The new form has been keyed out using a number of algal taxonomic keys. They key out now as being in the genus Coelosphaerium, which is in a different family from Chlorella.

And PZ Myers recently posted on an interesting beastie that is only slightly more organized than the colonial algae above in that it has "at least four functionally distinct cell types." Can we show an example of this trait evolving in front of us from a colonial organism with only one cell type in the same way that we've shown the development of improved and new functions? I don't know, there's a lot of work done in evolutionary biology that I haven't read, but let's say no. Given what we do know about what has actually happened (and there are many more examples, some less accessable to laymen like myself than the ones I've listed -- it is science and a lot of it does require quite a bit of study to understand,) is there any barrier to this having happened? I don't see one. In fact, I think that the burden here falls squarely on a skeptic to propose an alternative mechanism. Mutation and environmental selection seems quite capable of bridging this gap.

But back to Bethell.

We are expected to believe — and I do mean believe — that evolution answers the important question: How did life, in all its abundance, appear on Earth?

No, we are not expected to believe. We are allowed to question anything in science. But answers can be long and complicated and we are expected to do some research. Above, Bethell dismisses one small subset of the many examples of short-time selection experiments in one sentence. In answer, I made a few quick references to popular sources, which represent hundreds of pages of peer-reviewed work and thousands of hours of research that answers that objection. We aren't expected to believe it, but you are expected to do some work if we have questions. Bethell didn't do his homework.

Next, he asks us to consider the argument between the scientific consensus held by the vast majority of scientists and the Intelligent Design proponents.

Whom to believe? Or maybe we should approach it more scientifically: What are the facts?

If we discount trivial examples like bacterial resistance or "change over time" or small changes in beak size among the finches of the Galapagos Islands, we don't know very much about evolution at all. We don't see it happening around us, or in the rocks.

In my book, I quote Colin Patterson, a senior paleontologist at the British Museum of Natural History, telling a professional audience at the American Museum in New York that there was "not one thing" he knew about evolution. He had asked the evolutionary-morphology seminar at the University of Chicago if there was anything they knew about it, and, he said: "The only answer I got was silence."

Patterson, who died a few years ago, was an atheist and once told me that he regarded the Bible as "a pack of lies." There was no way he could be accused of Biblical primitivism. People would ask him, with a note of alarm, "Well, you do believe in evolution, don't you?" He would respond that science wasn't supposed to be a system of belief.

Whom should we believe? Whom did Colin Patterson believe? We have this to help us, which quotes Colin Patterson from Evolution:

"I see the general historical theory, common descent, as being as firmly established as just about anything else in history. We have compelling reasons to believe that Napoleon and the Roman empire existed, although we don't know every detail of what went on in Napoleon's life or in Rome and its colonies; it is much the same with evolution. There is abundant documentary evidence for Napoleon and the Roman empire; there is abundant evidence for common descent in the hierarchy of homologies at both the structural and morphological level, though those documents may not be so easy to read."

And

"Today's theory, accepting that evolution has occurred and explaining it by neo-Darwinism plus neutralism, is the best that we have. It is a fruitful theory, a stimulus to thought and research, and we should accept it until nature prompts someone to think of one that is better or more complete."

I think that is a fair answer. But let's step back a second and look at Bethell's question again: whom should we believe about what? The Intelligent Design debate is not really a scientific debate. Scientific debate occurs in journals and conferences. To my knowledge, Intelligent Design advocates have published exactly one paper (of dubious quality) on Intelligent Design.

The real Intelligent Design debate is about secondary school science education. And what should be taught in a secondary school science class is the scientific consensus. The scientific consensus is firmly with evolution and common descent; there is no debate about that.

Bethell wants to challenge the scientific validity of Evolutionary Theory, but he doesn't want to do the hard work involved in actually challenging it in peer reviewed journals. He goes on to list more objections to evolution, but each one is as empty as his objection to the evolution antibiotic resistance. And then he asserts of evolution that "it isn't real science."

Except that the vast majority of actual scientists -- even the ones that Bethell quotes to support his position -- claim that evolution is real science. Not only is it a real science, it is the current scientific consensus -- unless you accuse the scientific community of a near-universal dishonesty. And the scientific consensus is what belongs in a secondary school introductory science curriculum.

I was much amused by Bethell's closing zing at George Will's assertion that Intelligent Design was not falsifiable.

This is true; but he should have added that Darwin's theory of evolution by natural selection is not falsifiable either. Darwin's claim to fame was his discovery of a mechanism of evolution; he accepted "survival of the fittest" as a good summary of his natural-selection theory. But which ones are the fittest? The ones that survive. There is no criterion of fitness that is independent of survival. Whatever happens, it is the "fittest" that survive — by definition.

But Bethell is only complaining about the phrase "survival of the fittest," not about the actual mechanism of natural selection. Natural selection is simply a generalization from the type of observation that Bethell granted at the beginning of his piece with antibiotic resistance in a bacterial population. Natural selection could be falsified if there were no heritable morphological variations (such as long versus short fur) that can affect an individual's likelyhood of surviving to reproduction in a given environment (such as in Northern Alaska.)

In conclusion, Bethell provides us with an example of a conservative "talking nonsense" as Augustine put it. He is either arguing that the vast majority of scientists are involved in a conspiracy to lie to the public; or he is missing the point of the argument about what to require in a secondary school science curriculum by arguing against the science of evolution (and without doing his homework.) Reasonable people should not believe that scientists are involved in a world-wide conspiracy to deceive the public. And reasonable people should recognize that the required material for an introductory science course should be the current scientific consensus.