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Thursday, 4 February 2016

Is Macroevolution simply Microevolution squared?

Karl Giberson and Francis Collins Commit Berra's Blunder While Arguing for Macroevolution
Casey Luskin May 19, 2011 10:15 AM

In their new book The Language of Science and Faith, Karl Giberson and Francis Collins argue that "the distinction between micro and macro evolution is arbitrary." (p. 45, emphases in original) As a result, they assert that "macroevolution is simply microevolution writ large: add up enough small changes and we get a large change." (p. 45) What's most surprising is not that they make this claim (which is common in evolutionary writings), but the examples--or lack thereof--they give to back it up.
Their main illustration for macroevolution is the evolution of the automobile. "[N]obody could have imagined how Henry Ford's primitive T automobile could have turned into Toyota's Prius hybrid," they write, because "it would have been impossible for the engineers at Ford to develop all the remarkable engineering necessary to turn a Model T into a Prius in one year. The electronic enhancements alone took decades to invent and develop." (pp. 45-46)

Giberson and Collins have of course just committed what Phillip Johnson calls "Berra's blunder." Here's a snippet of Professor Berra's original blunder:

[I]f you compare a 1953 and a 1954 Corvette, side by side, then a 1954 and a 1955 model, and so on, the descent with modification is overwhelmingly obvious. ... the evidence is so solid and comprehensive that it cannot be denied by reasonable people.

(Tim Berra, Evolution and the Myth of Creationism, pp. 117-119 (Stanford University Press, 1990).)

If anything here is "overwhelmingly obvious," it's that Corvettes did not evolve by Darwinian mechanisms, but were intelligently designed. Phillip Johnson elaborates on Berra's blunder:

Of course, every one of those Corvettes was designed by engineers. The Corvette sequence - like the sequence of Beethoven's symphonies to the opinions of the United States Supreme Court - does not illustrate naturalistic evolution at all. It illustrates how intelligent designers will typically achieve their purposes by adding variations to a basic design plan. Above all, such sequences have no tendency whatever to support the claim that there is no need for a Creator, since blind natural forces can do the creating. On the contrary, they show that what biologists present as proof of "evolution" or "common ancestry" is just as likely to be evidence of common design.

(Phillip Johnson, Defeating Darwinism by Opening Minds, p. 63 (InterVarsity Press, 1997).)

The same goes for Prius hybrids: all of the innovations that led engineers to develop hybrids from Ford Model T's were intelligently designed, and did not arise by random mutations.

Direct Evidence Fails, So They Use Indirect Evidence
So the first argument used by Giberson and Collins to show that macroevolution is simply microevolution "writ large" seems to have failed. In fact, to their credit they acknowledge that "[w]e don't observe such macroevolutionary changes because they take such a long time" and therefore must use our "imaginations" to understand macroevolution. (pp. 46-47) Thus, they seek to provide indirect evidence of macroevolution, and in the next section ask, "Is there Proof of Macroevolution?"

The answer they provide, of course, is 'yes.' But guess what their evidence is? They fall back to again relying on pseudogenes: "The example of the broken vitamin C gene that we looked at earlier is a case in point" (p. 49), they write. As we already saw here and here, this is an incredibly weak argument, especially given that we're continually finding more and more functions for pseudogenes.

Big Claims, Small Evidence
Giberson and Collins claim that "[m]ountains of data arrive on a daily basis ... providing compelling evidence for macroevolution," (p. 49) but aside from a weak and assumption-based argument based upon a single pseudogene, Giberson and Collins do not specify exactly what that evidence is.

In a previous article we saw that Giberson and Collins essentially expected readers to take eye-evolution on faith. Now it seems that they also want their readers to take it on faith that "the distinction between micro and macro evolution is arbitrary," because they provide no empirical evidence to back up this claim other than a highly suspect and dangerous argument that a particular pseudogene is functionless "broken DNA."

Having failed to provide empirical data backing macroevolution, Giberson and Collns end their chapter on the evidence for evolution claiming: "All that evolution requires is enough generations to accumulate the sort of tiny differences that separate offspring from their parents and almost any transformation can be achieved." (p. 52)

Presto chango--evolution sounds so easy! But according to Darwin, evolution requires more than just "enough generations." Darwin acknowledged that evolution also requires a continuous evolutionary pathway:

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.

And it's here that macroevolution hits a wall, for there are many complex structures which cannot be built over "numerous, successive, slight modifications." Giberson and Collins promise to give "Straight Answers to Genuine Questions," but that's not the sort of analysis I am finding in their book The Language of Science and Faith.

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