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May 31, 2007

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It was not a fair question for sure to ask. One cannot explain themselves in 30 seconds. In light of the fact we have different definitions for evolution, it would have been nice if the moderator had specified what he meant...If he had said something like Do you believe in Evolution or that man was made from goo--to the zoo to you--???? Hum now that might have been interesting...

His explanation for why faith and reason cannot contradict each other is that they deal with completely different questions. I don't agree with that. It was reason that told us we could actually put people in orbit, but it was faith on their part to go up there in a space shuttle.

Two interesting comments, hat tip to Sullivan for the first:

From the right.

"Sam I Am [John Derbyshire]

Here is Sam Brownback talking about evolutionary biology. That's a bit like saying: "Here's Paris Hilton talking about partial differential equations"... from which you can deduce that I don't feel much inclined to offer a detailed critique of Brownback's position.

I would though like to draw attention to the following bit of weaseling.

"If belief in evolution means simply assenting to microevolution, small changes over time within a species, I am happy to say, as I have in the past, that I believe it to be true. If, on the other hand, it means assenting to an exclusively materialistic, deterministic vision of the world that holds no place for a guiding intelligence, then I reject it."

What's going on here is that Brownback has got a whiff of the notion that living species indisputably do change over time. This is so well established that the old creationist position—that species do not change over time—has had to be abandoned. Creationists have retreated to this new position: "Yes, OK, a given species does change over time, but never into a new species." You could summarize this as "micro-evolution yes, macro-evolution no." It's a common creationist line of argument.

The problem with this position is, that you need to observe—or at least, darn it, hypothesize—some mechanism that stops the micro before it goes macro. (Not to mention that you have to posit some mechanism, other than macro-evolution, for the origin of species... But leave that aside for the moment.)

Take, for example, allopatric ("different homeland") speciation. You have a population of living, sexually-reproducing organisms, all belonging to the same species (i.e. able to mate with each other). You observe variations within the population. You further observe, watching across several generations, that some variations (red hair, schizophrenia) are heritable in whole or part, some (appendectomy scars) are not heritable at all.

Now you divide your population in two: Population A and Population B. You separate them geographically. (Hence "diferent homelands.") You observe that A and B have different "menus" of heritable variation (A has more redheads, B more schizophrenics). You further observe that A's and B's environments are different—A's is hot and dry, B's cool and wet.

You sit back and observe for a few thousand generations. Yep, microevolution goes on. A changes, B changes. Because they started out with different menus of heritable variations, and because environmental pressures in the two places are different, they change differently. They diverge. A thousand generations on, the two populations look and behave differently from each other. Ten thousand generations on, they look and behave way differently. Orthodox biology ("Darwinism") says that eventually they will be so different, they can no longer interbreed. Speciation will have occurred. A and B are now two species.

Under Brownbackian evolution—micro yes, macro no—this can't happen. They can't go on diverging. They can only get so different, no more. The divergence must slow down and stop. But... what stops it? What's the mechanism?

I'm not expecting Sam, or any other creationist, to give me an answer. I do wish Sam had at least confronted the question honestly, though. Like this, perhaps:

If belief in evolution means simply assenting to microevolution, small changes over time within a species, I am happy to say, as I have in the past, that I believe it to be true. If, on the other hand, it means assenting to macroevolution, those small changes accumulating all the way to speciation, then I reject it.

And Sam at least has the interests of scientists at heart.

While no stone should be left unturned in seeking to discover the nature of man's origins, we can say with conviction that we know with certainty at least part of the outcome.

With certainty! Well, that should spare biologists a lot of futile research work!

05/31 01:09 PM"

http://corner.nationalreview.com/post/?q=MmMzNTY1YWJlOTZjMjAzYWFlMzE2Zjc5NzcxMGY1NDI=

(copuy this line to link)

And from the left:

"Thursday, May 31, 2007

No, Sam Brownback Doesn't Believe in Evolution

JB

Sam Brownback's essay in today's New York Times is an op-ed written by a skillful politician, trying to make the reader believe that he is merely attacking the materialistic and deterministic emphasis in science without doubting evolutionary processes, when in fact the real problem is that he just doesn't believe in evolution at all. The key passage is here:

The question of evolution goes to the heart of this issue. If belief in evolution means simply assenting to microevolution, small changes over time within a species, I am happy to say, as I have in the past, that I believe it to be true. If, on the other hand, it means assenting to an exclusively materialistic, deterministic vision of the world that holds no place for a guiding intelligence, then I reject it.


Brownback is denying that humans have a common ancestor with other species, because he only agrees to small changes within a species. The rest of the discussion, about materialism and determinism distracts from this central point. It offers a false dichotomy. One might think that the hand of God is involved in evolution in some way and still believe that mankind evolved from previous forms of life. It is this latter point that Brownback wishes to deny, because he wants to insist that mankind is special. As a result, he is willing to acknowledge only that species might experience "microevolution," i.e., small changes, without evolving into new species.

Brownback's views are clever political sophistry, claiming to reject a false choice, but in fact offering his own false choice. He is not a defender of faith against science. He is a defender of ignorance."

Posted 10:27 AM by JB [link]

http://balkin.blogspot.com/2007/05/no-sam-brownback-doesnt-believe-in.html

(copy to this line to link)

There are also a lot of comments on Balkin's post that i didn't copy.

"The divergence must slow down and stop. But... what stops it? What's the mechanism?"

It's the limited amount of genetic material available within a population and the limited number of ways in which that genetic material may combine.

Sure, two isolated populations with drastically different climates may "change" over time as those with traits less suited for each climate are "weeded out." But they're not changing in the way that you seem to think they are. The populations, in fact, are actually losing undesirable genetic material over time, and they end up reflecting only that subset of the original genetic material that is left over.

The change, therefore, stops when the undesirable genetic material has been purged from the population and the undesirable traits are no longer around. Or, in our case, when technology makes such weeding out unnecessary and in many cases impossible.

Well said, Derek.

All we learn from finches with different sized beaks is that they have a flexibility within already present combinations that allow for long and short beaks. The short beaked Finch didn't "evolve" the ability to grow a long beak. The information to do so was already in his DNA.

What the macro-evolutionist needs to produce is information gain in the DNA. Purely natural processes don't seem to create the information in the language that is DNA. It can LOSE information in DNA due to mutation but I want to see the model where it gains the ability.

Derb's got it right, Alan. The "commenter on the left" you quote is just playing games, assuming that Brownback's position is wrong without explaining why. (Yes, he may have correctly analyzed the root psychological cause of Brownback's opinion -- but that's not the same as actually refuting his opinion.)

But Derb's got a great rebuttal.

Personally, I'd say that a good answer is that the limiting mechanism is observed to be natural selection and the error correction built into the DNA. I personally don't know that's *enough* of a limiting factor -- in other words, I don't know whether Darwinian "macroevolution" is possible. It may be. I certainly see some evidence that it's actually occurred, and some very intelligent people agree.

But some don't, and they tend to point out that the limiting factors that we know about seem to require much more time to get around by means of mutation than we've actually got.

BUT... anyhow, Derb's asking the right question.

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