June 6, 2002

Intelligent Design as an alternative to Evolution

Intelligent Design as an alternative to Evolution Glenn Reynolds posts a link to Ian Murray's TAP article blasting Intelligent Design. Glenn concurs with Murray's conclusions, which just goes to show that knowledge in one area does not automatically convey knowledge in another.
We have a lawyer agreeing with a statistician/programmer about a theoretical biological process that neither has taken the time to examine.

Murray starts off by citing the Popper doctrine, that if a theory is not falsifiable, it is not science. I disagree with this position as being way too limiting. Many scientific theories were not testable when they were first proposed, Much of the work which laid the foundation for Einstein’s Special and General theories of Relativity, not to mention the entire field of quantum electrodynamics was done decades before the technology to test the theories could catch up to the imagination. Should those theories have been junked because they weren’t immediately testable? Einstein said he saw far because he stood on the shoulders of giants. Suppose those giants had been discredited by Popperites?

Murray later concludes that even if we reject Popperism, ID still fails as it is not part of a paradigm shift, because it’s main proponent is a lawyer. This is quite simply not true. As Behe demonstrates in his book, there is a growing dissatisfaction with Neo-Darwinism throughout the scientific community. As a few examples:

“[History will ultimately judge neo-Darwinism as] a minor twentieth century religious sect within the sprawling religious persuasion of Anglo-Saxon biology.” Lynn Margulis, Distinguished University Professor of Biology, Umass.

“No wonder paleontologists shied away from evolution for so long. It never seems to happen. Assiduous collecting up cliff faces yields zigzags, minor oscillations, and the very occasional slight accumulation of change---over millions or years, at a rate too slow to account for all the prodigious change that has occurred in evolutionary history. When we do see the introduction of an evolutionary novelty, it usually shows up with a bang, and often with no firm evidence that the fossils did not evolve elsewhere! Evolution cannot forever be going on somewhere else. Yet that’s how the fossil record has struck many a forlorn paleontologist looking to learn something about evolution.” Niles Eldredge, Paleontologist.

“[Stephen Jay] Gould has been at the forefront of the discussion of another fascinating phenomenon: the “Cambrian explosion.” Careful searches show only a smattering of fossils of multicellular creatures in rocks older than about 600 million years. Yet in rocks just a little bit younger is seen a profusion of fossilized animals, with a host of widely differing body plans. Recently, the estimated time over which the explosion took place has been revised downward from 50 million years to 10 million years--a blink of the eye in geologic terms.” Michael J Behe, in “Darwin’s Black Box”

“We conclude---unexpectedly---that there is little evidence for the neo-Darwinian view; its theoretical foundations and the experimental evidence supporting it are weak.” Jerry Coyne, Department of Ecology and Evolution at the University of Chicago.


These are not crackpots on the fringe, but respected scientists whose research has lead them to question evolution. Lynn Margulis in particular did some excellent work on cellular evolution, and proved that the mitochondria, an organelle which provides the cell with energy, actually evolved as a separate unicellular organism, before becoming absorbed into a more complex cell. She used this to propose a new model for evolution, one that depended on co-operation or symbiosis rather than competition and natural selection.
It certainly seems possible that we are seeing the beginnings of a paradigm shift. It may not lead to Intelligent Design, but it certainly seems to be leading away from Neo-Darwinism.
Notice that to this point, Murray does not rely on science to debunk ID, but on philosophy. He does turn to science in the middle of his article, giving a concise summary of Behe’s defense of “irreducible complexity.” However, he relies on Richard Dawkins’ essay The Improbability of God, another philosophical argument, to deny Behe’s proposition. In this essay, Dawkins argues that physical features of the eye could very well have arisen gradually, through natural selection, as slow improvements in form and function yielded traits advantageous to the organism. But in doing so, Dawkins avoids the central issue of Behe’s theory. It isn’t the physical complexity of the eye that confounds Neo-Darwinism, but the biochemical complexity. The biochemistry of vision breaks down if one reagent is missing. The system doesn’t just function poorly; it ceases to function entirely. Gradual development is ruled out in this case. Now, it is clear that evolution does not always proceed gradually, that there are periods of tremendous change over relatively short periods of time, but listen to what Dawkins himself has to say about that:
”Evolution is very possibly not, in actual fact, always gradual. But it must be gradual when it is being used to explain the coming into existence of complicated, apparently designed objects, like eyes. For if it is not gradual in these cases, it ceases to have any explanatory power at all. Without gradualness in these cases, we are back to miracle, which is simply a synonym for the total absence of explanation.”

In another example of irreducible complexity, Behe cites the action of cilia. The cilium is a cellular component that works basically like an oar, sweeping through fluid to propel the cell in some organisms, or to move fluids in others. The cilium consists of several components, all of which are necessary for the function of motion. Microtubules clump together to form long strands, which are linked together to form the “tail”. In addition, two arms project from the exterior microtubule. The cilia functions as follows; when chemical energy is applied, the arms “walk” the strands, sliding them past one another. The linkers holding the clump together prevent the microtubules from sliding too far, placing a strain on the bundle, which bends, producing the sweeping action. All three structures are required for the sweeping motion to occur. Without any of these, the cilia would be useless. Here’s the kicker; these components are all proteins. Their shape and properties are defined by chemistry. They don’t evolve; that is to say, small changes in structure do not lead to small changes in function; rather, small changes in chemical structure yield major changes in function.
This is a highly simplified picture of a cilium. In actuality, there are over 200 proteins that make up a cilium; however, the three that we have discussed are sufficient to form an irreducibly complex system, which could not have evolved through natural selection.
Lynn Margulis tackled this problem, trying to prove that cilia evolved from the absorption of bacterial flagella, similar to her earlier work with the mitochondria. Unfortunately, the biochemistry and the mechanics of flagella and cilia are so completely different that her hypothesis was untenable.
Murray points out that the majority of biologists do not accept the theory of ID or irreducible complexity, as if that automatically condemns the theories. It wasn’t that long ago that the majority of physicists, including Einstein himself, rejected quantum theory. It wasn’t much longer before that when the majority rejected relativity. What ‘everybody knows’ today is often completely discredited tomorrow. While we shouldn’t throw Neo-Darwinism out, we do need to continue to ask questions. Behe and the ID proponents are asking hard nuts and bolts questions that need to be answered, either by Neo-Darwinism, or a new, more robust theory. Some biochemists are postulating that biochemical systems evolved with ‘redundant’ complexity, or with extra proteins and enzymes manufactured by the cell to perform similar functions. Precursor complex systems could have disappeared as simpler, more efficient forms appeared over time, eventually resulting in a system that is irreducible, because it has been reduced to it’s minimal configuration. This theory would explain irreducible complexity without requiring ID, yet like ID, it is untestable.

Quoting Dawkins one last time:

The fossils tell us that life has been evolving on Earth for more than 3,000 million years. It is almost impossible for the human mind to grasp such an immensity of time. We, naturally and mercifully, tend to see our own expected lifetime as a fairly long time, but we can't expect to live even one century. It is 2,000 years since Jesus lived, a time span long enough to blur the distinction between history and myth. Can you imagine a million such periods laid end to end? Suppose we wanted to write the whole history on a single long scroll. If we crammed all of Common Era history into one metre of scroll, how long would the pre-Common Era part of the scroll, back to the start of evolution, be? The answer is that the pre-Common Era part of the scroll would stretch from Milan to Moscow. Think of the implications of this for the quantity of evolutionary change that can be accommodated. All the domestic breeds of dogs - Pekingeses, poodles, spaniels, Saint Bernards, and Chihuahuas - have come from wolves in a time span measured in hundreds or at the most thousands of years: no more than two meters along the road from Milan to Moscow. Think of the quantity of change involved in going from a wolf to a Pekingese; now multiply that quantity of change by a million. When you look at it like that, it becomes easy to believe that an eye could have evolved from no eye by small degrees.

I’ll let a geneticist answer this one:

“The results of the last 20 years of research on the genetic basis of adaptation has led us to a great Darwinian paradox. Those [genes] that are obviously variable within the natural populations do not seem to lie at the basis of many major adaptive changes, while those [genes] that seemingly do constitute the foundation of many, if not most, major adaptive changes apparently are not variable within natural populations.” John McDonald, Geneticist at UGA

In other words, a wolf may become a chihuahua, but it won’t become a chicken.

Finally, quoting the man himself:

“If it could be demonstrated that any complex organ existed which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down.” Charles Darwin

I'm sure that when Charles Murtaugh returns, he will teach me the error of my ways.

Posted by Rich at June 6, 2002 2:38 AM