How Kenneth Miller Used Smoke-and-Mirrors to Misrepresent Michael Behe on the Irreducible Complexity of the Blood-Clotting Cascade (Part 2) - Evolution News & Views

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How Kenneth Miller Used Smoke-and-Mirrors to Misrepresent Michael Behe on the Irreducible Complexity of the Blood-Clotting Cascade (Part 2)

In Part 1, I showed how Ken Miller misrepresented Michael Behe's arguments about the irreducibility of the blood-clotting cascade to Judge Jones during the Kitzmiller v. Dover trial, such that Judge Jones wrongly ruled that "scientists in peer-reviewed publications have refuted Professor Behe's predication about the alleged irreducible complexity of the blood-clotting cascade." To briefly recap, Miller told Judge Jones that Behe's discussion of the blood-clotting cascade in Darwin's Black Box was "essentially identical" to the discussion of the blood-clotting cascade in Of Pandas and People, implying that any critiques of Pandas also applied to Behe. But unlike Pandas, Behe explicitly did not argue that all of the components of the blood-clotting cascade were required for it to function properly. In fact, the evidence that Miller presented at trial used comparative biochemistry to show that the blood-clotting cascade still worked in the absence of certain blood clotting factors, but these missing factors were ones that Behe explicitly did not argue were part of the irreducibly complex core of the blood-clotting cascade. Miller in no way refuted Behe, and as I will show in this second installment, Miller probably didn't even refute Pandas.

Pandas May Still Be Correct
As I discussed in Part 1, Pandas contended that the blood-clotting cascade of land-dwelling vertebrates requires all of its parts--including the intrinsic pathway, the extrinsic pathway, and all of the components that the pathways share in common after they converge (i.e. from factor X onward). The blood-clotting cascade of land-dwelling vertebrates, with the intrinsic and extrinsic pathways labeled, is seen in Figure 1 below:

Figure 1: The figure below shows the full blood-clotting cascade of land-dwelling vertebrates. Jawed fish lack the intrinsic pathway found in humans and all other land-dwelling vertebrates. Miller's logical mistake was assuming that this fact therefore implies that the intrinsic pathway is therefore dispensable to the blood-clotting cascade of land-dwelling vertebrates. Perhaps it is dispensable, but Miller's evidence did not show that (click on graphic to see the full diagram):

Diagram_Behe_smf.JPG
(Information sources for figure: Of Pandas and People, Darwin's Black Box, Wikipedia, Barbara Forrest, Paul Gross, "Biochemistry by design," Trends in Biochemical Sciences, Vol. 32(7):301-310 (2007).)

Miller argued that because dolphins and jawed fish lack some components of the intrinsic pathway, that this shows that the entire land-dwelling vertebrate blood-clotting cascade is not irreducibly complex. But this is not a valid argument: Miller's logical mistake was to forget that the fact that two systems are different, or the fact that System A does not have certain parts found in System B, does NOT necessarily mean that System A could evolve into B along a stepwise evolutionary path, or that system B is not irreducibly complex.

For example, consider again the bicycle. Bicycles have two wheels. Unicycles, having only one wheel, are missing an obvious component found on bicycles. Does this imply that you can remove one wheel from a bicycle and it will still function? Of course not. Try removing a wheel from a bike and you'll quickly see that it requires two wheels to function. The fact that a unicycle lacks certain components of a bicycle does not mean that the bicycle is therefore not irreducibly complex.

Miller assumed that since jawed-fish / dolphins lack certain components found in the intrinsic blood clotting pathway of land-dwelling vertebrates, that therefore the land-dwelling vertebrate blood-clotting cascade is NOT irreducibly complex. But Miller didn't cite an experiment that demonstrated that the blood-clotting cascade of land-dwelling vertebrates doesn't require the intrinsic pathway. In other words, he never tried removing a wheel from the bike, which is the proper experiment to show that a bike is reducibly complex. Instead, Miller effectively said unicycles only have one wheel, so bikes don't need both wheels. It's an experimentally deficient and logically flawed argument.

Arguments about the irreducibly complex core aside (see Part 1), the entire land-dwelling vertebrate system might still be irreducibly complex, for the fact that some vertebrates lack factor XII (called Hageman Factor) in their blood-clotting cascade, or even lack the entire intrinsic pathway, in no way implies that humans (and other land-dwelling vertebrates) don't require all of these components for their blood to clot. Miller didn't cite the proper experimental data to show that the land-dwelling vertebrate blood-clotting cascade is reducibly complex. He just cited a unicycle, which as we've seen, isn't sufficient to demonstrate the point he's trying to make. Miller could only make this argument if he presented actual knockout experiments on the blood-clotting cascade of land-dwelling vertebrates that removed certain components from the blood-clotting cascade, and found that the blood still clotted properly. But Miller didn't do anything like that.

In fact, no one has demonstrated an evolutionary pathway from the blood-clotting cascade of jawed fish to the blood-clotting cascade of land-dwelling vertebrates. In contrast, as Behe observes in Darwin's Black Box, the blood-clotting cascade is irreducibly complex with respect to the extrinsic pathway and everything after the intrinsic and extrinsic pathways converge, i.e. from factor X onward (see the red box in the diagram below). As usual, Darwinists have used bogus comparisons to other living organisms to find other systems which COULD represent islands along an evolutionary pathway, but they need MUCH more evidence to demonstrate that the pathway exists.

Figure 2: This diagram shows the blood-clotting cascade of land-dwelling vertebrates. The red box shows the components that Michael Behe argues form the irreducibly complex core of the blood-clotting cascade. The green box shows the components which Ken Miller claims are dispensable to the blood-clotting cascade. Since the boxes don't overlap, it can be seen that Miller didn't even address Behe's arguments. Nonetheless, Judge Jones had the gusto to rule that "scientists in peer-reviewed publications have refuted Professor Behe's predication about the alleged irreducible complexity of the blood-clotting cascade."

Diagram_BeheRed_Green.jpg
(Information sources for figure: Of Pandas and People, Darwin's Black Box, Wikipedia, Barbara Forrest, Paul Gross, "Biochemistry by design," Trends in Biochemical Sciences, Vol. 32(7):301-310 (2007).)

Revealing Differences Between the Blood-Clotting Cascade of Land-Dwelling Vertebrates and Dolphins / Jawed Fish?
During the Kitzmiller trial, Ken Miller discussed the fact that dolphins (like jawed fish) lack factor XII (Hageman factor) in their blood-clotting cascade. This is interesting: Dolphins are supposedly descended from land-dwelling vertebrates (which have factor XII) but their condition is like jawed fish, which lack factor XII. This implies that there may be functional constraints on water-dwelling vertebrates to have a different activation pathway than land-dwelling vertebrates.

Darwinists like Ken Miller view the dolphin's lack of factor XII as a case of convergent evolution, but we might also see it as evidence of a functional constraint or a case of common design. The fact that jawed fish lack factor XII is not necessarily evidence that their blood-clotting cascade was a "primitive evolutionary precursor" to the land-dwelling vertebrate blood-clotting cascade, but evidence of a functional constraint for water-dwelling vertebrates--a constraint which is confirmed in that dolphins also lack factor XII.

This is an interesting issue that will require further research to sort out. In the mean time, any claims that Miller refuted Behe--or even Pandas--appear to be premature.


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