Thursday, June 5, 2008

Genetics and Evolution

We have seen (in recent posts) that microevolution (as in the development by bacteria of resistance to antibiotics) is irrelevent to the issue of whether evolution accounts for the diversity of life and that the fossil evidence does not support neo-Darwinism. There is one other claim made by those unfamiliar with the evidence, here represented by a comment I received a few weeks ago...
DNA profiles show evolutionary relationships among species. There was no field of genetics when Darwin published the Origin of Species. The development of the field of genetics stood to topple natural selection. It turned out to be one of the strongest demonstrations of the fact of evolution there is.
There are several problems with this appeal to genetics. First, the claimant wrongly implies that evolutionists made predictions about what genetics would reveal, and that those predictions were validated. Conversely, the implication could be that theism made predictions that were falsified by genetics. Neither is true.

Darwinian evolution quite simply persists because its proponents explain away contrary evidence in the relatively few cases where predictions were made in the first place. Modern evolutionary theory is not predictive, but reactive. And 'just-so stories' after the fact are much more numerous than are cases of evidence actually fitting a priori expectations. According to Behe,
...reasoning straightforwardly in terms of Darwin's theory led badly astray even the most eminent evolutionary biologists, who reached conclusions completely opposite to biological reality.
Behe lists several examples, of which I'll quote just two. The first is from Francois Jacob...
When I started in biology in the 1950s, the idea was that the molecules from one organism were very different from the molecules from another organism. For instance, cows had cow molecules and goats had goat molecules and snakes had snake molecules, and it was because they were made of cow molecules that a cow was a cow.
Today, of course, we know this idea to be false. And, to be sure, this finding is not fatal to neo-Darwinism, but that's not the point. The point is that biochemistry and genetics did not validate the Darwinian expectation--it refuted it.

Incidentally, the Bible (indeed, portions of it written 3500 years ago) claimed just what modern science has verified--that humans are made of the same 'stuff' as other animals. Genesis 2:7 has the physical part of humans being formed from the 'dust of the ground,' whereas verse 19 of that chapter tells us that the same is true of "every beast of the field and every bird of the air." In more modern terms, all life is formed of the very same elements of which the earth's crust is composed. As late as the 1950's, Darwinian theory apparently led its believers to expect otherwise.

Here's Behe's second example...
In the 1960s, Ernst Mayr, an architect of the neo-Darwinian synthesis, confidently predicted on Darwinian grounds that "the search for homologous genes is quite futile," of which Sean Carroll notes, "The view was entirely incorrect."
And here's the take-home message (from Behe, in answer to my anonymous Darwinbot),
In retrospect, it is astounding to realize that the strong molecular similarity of life, which Darwinists now routinely (and incorrectly) appropriate as support for their entire theory, was not anticipated by them. They expected the opposite.

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