As many of the other Sciencebloggers have already mentioned, Casey Luskin of the Discovery Institute is up to his usual stupidity. In this particular instance, he's attempting, in a typically inept fashion, to fisk Carl Zimmer's recent article in National Geographic. So far, I haven't chimed in, mostly because everyone else has done such a good job that there wasn't much to add.
Today, though, Karmen pointed out a passage that I'd somehow missed the first time I read Luskin's piece. In the first part of his "rebuttal," Luskin wrote:
The article called evolution a "simple" process. In our experience, does a "simple" process generate the type of vast complexity found throughout biology?
Karmen and PZ have both already pointed out the silliness of claiming that simple processes can't lead to complex results. I'm going to talk about something different, but every bit as silly: the idea that evolution is a simple process.
Before I go on, I should probably take a minute to preempt the inevitable claim that Casey wasn't the one claiming that evolution is a simple process, and that he was simply quoting Zimmer's article. In fact, aside from the word "simple," he wasn't. Here, again, is what he wrote:
The article called evolution a "simple" process. In our experience, does a "simple" process generate the type of vast complexity found throughout biology?
And here is what was actually written in Zimmer's article:
"The basic idea of evolution is so elegant, so beautiful, so simple," says Howard Berg, a Harvard researcher who has spent much of the past 40 years studying one of the humbler examples of nature's complexity, the spinning tail of common bacteria. "The idea is simply that you fiddle around and you change something and then you ask, Does it improve my survival or not? And if it doesn't, then those individuals die and that idea goes away. And if it does, then those individuals succeed, and you keep fiddling around, improving. It's an enormously powerful technique."
The difference between saying that the basic idea of evolution is simple and saying that the process of evolution is simple might appear to be trivial, but it is not. The basic idea of natural selection is simple and easy to understand, and that basic principle is an important part of the process. Natural selection is only one factor involved in the process of evolution, though, and even natural selection can be much more complex in practice than you might expect if all you know about it is the simple formulation given by Berg.
A good analogy for this might be gravity. It might be possible to simply state the basic idea of gravity (Big things attract little ones). It might even be possible to put together a series of examples which are pretty simple. The earth is so massive, compared with everything that is on it, that it is the only gravitational force that needs to be considered when working problems that involve objects near its surface. If you have two bodies way, way out in interstellar space that are near each other and far, far away from everything else, predicting their motion relative to each other over short time scales becomes a relatively simple exercise. Other, more realistic situations, on the other hand, are nowhere near as simple. If you try to predict the motions of a body of asteroids that are near each other, you quickly find that the motion of each asteroid is going to have an effect on the motion of every other asteroid, and that these effects are all taking place simultaneously.
Similarly, the effect of natural selection on a single trait in a single species can appear to be relatively simple. You can determine how much the trait helps (or hurts) the chances of reproduction, look at factors like the rate of reproduction and the proportion of organisms with that trait, and determine how the proportion of organisms with the trait is likely to change in the next few generations. And there are some situations that can be treated that simply. But then you get the more complex situations. How favorable a certain trait is in a prey population, for example, might depend on the size of the predator population, but the size of the predator population in turn depends on how much prey each predator can catch, and how much prey the predator can catch is in part determined by how many of the prey possess the trait in question - and all of a sudden you find that even a simple model of what's going to happen to the trait involves things like simultaneous differential equations.
It's also worth noting that even those more complex examples I just gave are actually relatively simple compared with reality. The position of all of those asteroids relative to each other is also determined by the gravitational effects of very large, but distant, objects like the sun and Jupiter. The trait in the prey might also be influenced by how common a different trait is in the predator population, or by the effect that the trait has on the way that the prey population interacts with a parasite.
Even there, we are still in territory that is simple compared with reality. The path of a comet might be modified by propulsion caused by the evaporation of gasses as the heat from the sun boils off ices from the comet. The frequency of a trait may change due to random factors in a small population, or as the result of immigration and emigration. And we are still just scratching the surface here.
If you want to understand - really understand - the process of evolution, you need to understand and be able to integrate information from a wide range of disciplines. At a bare minimum, you are going to need a foundation in genetics, population genetics, population biology, general ecology, biogeography, and statistics. I'm sure I'm leaving things off that list, too, and there are probably going to be some semi-irate comments left as a result.
Natural selection is a simple idea. Evolution is a complicated process.
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I'm going to be nitpicky, and note that this isn't quite true -- things attract each other, regardless of size. But since it's the same attractive force on each, the effect on the smaller thing is more noticeable. Aside from that, this is a nice post.
I appreciate the point you are making. To be even more nit-picky than Davis, though, it looks as if you intended the word "one" in this sentence, but it's missing in the spot indicated:
Natural selection is only one? factor involved in the process of evolution, though,
Fixed it, thanks.
Not if you were Casey.
If I had to create a verb for unscientific writings full of false claims, wrong or inacurate citations, quote mined, misrepresented or pub-jacked statements "to lusky" would be one of my favorites.
Taking a page out of Savage Love's book are you?
The only concern I have is that Casey might not be the ultimate practitioner of this art.
Maybe we should do one of those polling things to see whose name really personifies the concept.
Might the term "nonlinear" be applied, here?
Darwinists do tend to oversimplify things. Darwinists often answer tough questions with vague answers and tend to have a condescending "elementary, my dear Watson" attitude towards Darwinism's critics. For example, Darwinists often define co-evolution as simply the result of "mutual evolutionary pressure" between two kinds of organisms, or something like that. But when you look at the details, co-evolution does not seem so simple after all -- see, for example, http://im-from-missouri.blogspot.com/2006/09/co-evolution-redux.html
The comparison with gravity is excellent.
Though, the general n-body problem is merely the start of the complexity. There has been a series of gravitation theories improving on "stone descends, smoke ascends" and consequently general relativity has a lot of twists just as evolution. Marrying special relativity with gravitation makes SR spacetime to transform into foliations that describes a preferred time, if one gets a solution at all. To get at those it seems a number of energy and path conditions comes up. Then there are the singularity descriptions with black holes and big bang, cosmologies and the unique problem with reconciling GR with QM.
The gravitation books I've seen are all tomes. Of course, the goddIDit gravitation science would be "gods separates the smoke from the stones, don't ask for a pathetic level of detail".
"Darwinists do tend to oversimplify things."
Scientists works according to Einstein's maxim: "Everything should be made as simple as possible, but not simpler." Of course scientific models are as detailed as needed.
What you are discussing is probably discussions with IDists. Unfortunately, even efforts to simplify descriptions and start from the basics are usually stumped since creationists are unable, for dogmatic or educational reasons, to understand or accept the concepts.
The difference is "elementary, my dear Watson".
It might be possible to simply state the basic idea of gravity (Big things attract little ones).
Um, if you know virtually nothing about a subject, you probably shouldn't use it as an example. The basic idea of gravity is that all objects attract each other; sheesh. Slightly less basic is that the attractive force of an object is proportional to its mass, so heavy (not big) objects attract with more force, and the attraction decreases with distance (specifically, proportional to the square of the distance).
Beyond that, your argument generally sucks, as it's about the difficulty of predicting the detailed outcomes of process of evolution, rather than about the process itself. It's like saying that shuffling a deck of cards is a very complicated process because you would have to know all the details about your hand muscles, card elasticity, etc. in order to predict the outcome. It's much more straightforward to point out that simple processes applied to complex data streams can result on complex outcomes.