Evolution Fact or Fable? by J. Robert Kirk J.D

Author:J. Robert Kirk, J.D.
Language: eng
Format: epub
Publisher: Covenant Books
Published: 2022-06-22T19:50:16+00:00

Figure 12. Galapagos finch species (plus one from the Cocos Island).

Such microevolution actually has been cataloged by a British husband and wife team from Princeton University, Peter and Rosemary Grant. The Grants probably know more about Darwin’s finches than any other people on earth. They have conducted months long field studies of the finches on the Galapagos Islands annually since 1973. They have captured, tagged, and carefully measured finches each and every year—focusing mainly on one variety known as medium ground finches on one particular island.

The Grants have actually observed microevolution in progress. In 1977, the islands suffered a severe drought—resulting in the death of 85 percent of the medium ground finches. Varieties with thicker stronger beaks did better because they were able to crack the larger nuts of plants that had survived the drought. The Grants’ measurements in subsequent years showed that finches that survived the drought had slightly bigger bodies and bigger beaks than the pre-drought population. “In other words, the Grants had meticulously documented evolution in the wild by variation, selection and inheritance—a feat that had eluded Charles Darwin himself—and very likely the same sort of process that accounted for all the differences among the Galapagos finch species.”139

So if the Grants actually saw evolutionary changes in just a few decades, what amount of change had occurred in these geographically isolated finches during roughly two million years worth of that very same sort of evolutionary process?

The results…produced by all that frenetic Darwinian evolution is a twofold variation in body length, shorter or longer beaks of greater or lesser depth, and not much else. Beginning with something very much like a finch, Darwinian processes labored long and mightily in the Galapagos and brought forth…a finch.140

Indeed, it is not even clear that all that evolution actually produced fourteen different species of finches. The Grants’ careful observations for decades have produced many reports of interbreeding among finches thought to be of different species, which sometimes produces young more vigorous than their parents. Indeed, one “species” known as the large tree finch has apparently disappeared from one of the Galapagos Islands as the result of such crossbreeding. Such observations have produced an ongoing debate driven by some who now contend that what were thought to be fourteen species of finches may actually be not more than a handful of species.141

After two million years of natural selection, the finches are still finches. So Darwin’s extrapolation from micro to macroevolution certainly did not occur in Darwin’s finches. Why not?

To answer this question, we need to look beyond the bodies and beaks of birds and examine their genetics in great detail. Michael Behe starts by pointing out that the technology required for these important genetic studies has only recently been created.

For the rigorous study of evolution, however, it’s not nearly enough to just have knowledge of current biological processes—one has to be able to determine which particular mutations have occurred in individual organisms and what their effect has been…Experimental tools to sequence DNA developed only very slowly in the 1960s and 1970s and then explosively in the 1990s and later.

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