tgamble

I read somewhere that he accepts common descent, but rejects macroevolution....

bluefugue

Isn't that a contradiction?

theyeti

He accepts macroevolution. There's no reason why he would complain that the evidence isn't complete, because he's apparently convinced by the evidence.

Behe's claim concerned the evolution of complex biochemical strucutures and/or pathways. I forget the exact words he used, but the claim was generally incorrect. There are/were papers, conferences, books, etc. about these things, though they are generally obsure. It would have been better for him to claim that they were rare rather than non-existant. It's not wise to make claims of non-existance, because it's highly likely that at least one counter-example has escaped one's attention.

Behe made a similar claim about the Journal of Molecular Evolution that was similarly incorrect. There is at least one paper that comes to mind, detailing the evolution of the Krebs cycle, that existed prior to Behe's remarks. Had he simply stated that such papers were rare, he would have been right. JME does focus largely on sequence data, but this is simply because it's one of the only types of data that can be obtained and studied -- these things don't leave fossils ya know. And scientists don't get tend to get published unless they have some sort of data to present.

Moreover, detailed explanations of evolutionary pathways shouldn't be expected until after tons of data from a variety of studies are availiable, thus Behe's demand that these speculations be brought forth now is totally unreasonable. The sorts of systems that he applies his critiques to were discovered realtively recently, and in many cases the mechanisms of function are not yet well understood -- yet Behe claims that Darwinian evolution fails without an immediate plausible evolutionary pathway, the very thing that is actually the pinnacle of our understanding of biological phenomena. What really irritates me is that when someone does bring forth such speculations, sometimes to generate testable hypotheses, sometimes to counter creationist impossibility claims, Behe et al will accuse scientists of making up "just-so" stories. You're damned if you do and damned if you don't.

Re: bleen whale embryonic teeth. I'm surprised that you would claim that this is "the closest thing to evidence of macroevolution". It certainly is evidence of macroevolution, but it is only one out of many different lines of evidence. I wasn't able to find any original articles in PubMed with a brief search, but the claim that baleen whale embryos have teeth is a very common claim that I've never seen disputed -- I would be extremely surprised if it weren't true. For example, the claim is made at this talkorigins page: <a href="http://www.talkorigins.org/features/whales/" target="_blank">The Origin of Whales and the Power of Independent Evidence.</a> Notice, among other things, that there are numerous lines of evidence, not just embryology, that demonstrate the evolution of whales from land animals. Here is the section on embryos with teeth:

If you're really interested, there is an extensive reference list at the bottom of the article that probably contains a citation to the orginal research on this.

theyeti

tgamble

Yes. What's your point?

<a href="http://www.world-of-dawkins.com/Catalano/box/nature.htm" target="_blank">http://www.world-of-dawkins.com/Catalano/box/nature.htm</a>

"Behe's response to these problems constitutes the major weakness of his theory. He chews on the idea of morphological evolution, but cannot bring himself to swallow it. He finds the idea of common descent of all organisms "fairly convincing", and admits that microevolution occurs within species, but sees no evidence for transitions between major forms. (How one can admit common descent but deny macroevolution is one of the fascinating questions Behe leaves unanswered.)"

Kevin Dorner

I'm wondering if Behe isn't having just that: a conflict of faith. Behe's a Catholic, and the Vatican accepted theistic evolution a long time ago (and once they did so, Catholic schools taught evolution properly, not watering it down or belittling or strawmanning it, or offering it amongst a panoply of other ideas, and making sure the terminology was correct so that it would not be misunderstood.)

The Pope recently reaffirmed this after a long study by the Vatican.

Now, given that Behe is a Catholic, and the doctrine of papal infallibility is (still) in place, what would happen if he declared all tenets of evolution to be incorrect or impossible, in a very public manner? He'd be directly contradicting Papal decree, which would be grounds for excommunication. So he's either going to waffle a lot, or have to convert to something fundy.

Incidentally, the recent "education" bill passed in the U.S. is going to lead to an interesting conclusion: at least until the establishment clause challenge that overturns this silliness, public schools will be allowed to present other design "theories" (which has the effect of making them seem valid.) Catholic schools won't be doing this. So the fundies have made the U.S. into a nation where if one wants to hear a major scientific theory given proper treatment, one has to go to a religious school!

[ January 02, 2002: Message edited by: Kevin Dorner ]</p>

Ernest Sparks

Yes, Professor Behe doesn't reject macroevolution. His "irreducible complexities" cast doubt on some individual step-by-step variation-and-selection mechanisms. For example, blood clotting factors would take a whole string of individual genetic variations before a selective advantage would arise, namely, safety from bleeding to death. In a way what he raises is a cloud of doubt over the strict requirement for selective advantage in development.

Peregrine

Naw, Behe is just an opportunist. He sees $$$$.

There is no money to be made as an "evolutionist." And his credentials in evolutionary biology is non-existant.

But, ID needs some scientific credibility, and there is money to be made writing a book and speaking at church gatherings.

hedonologist

I said, it is the closest thing I have heard. I don't claim to know all that is known on any subject. Many arguments for evolution that I have heard are not so convincing, so I wasn't so motivated to dig through the claims of evolutionists, looking for evidence that would convince me.

Thanks for the info, friend. It looks convincing from the surface so will look into it. I would want to see exactly what they are calling "teeth", and "hair". Maybe you recall some "scientists" who thought they were seeing bacteria in a rock from Mars, and they even did DNA tests on them. Another group reviewing their experiments found that they were not looking at organisms at all and their DNA tests were probably of common air born bacteria.

Assuming these are teeth and hair, I can think of a few other hypotheses, off hand. First, if some creators had limited powers, they may have made baleen whales out of toothed whales. So even proving a common ancestor does not necessarily prove that anything "complex" (like baleen) came about by natural selection.

Or maybe baleen whales and toothed whales had a common ancestor but God designed them from the beginning to adapt to different niches via processes different from natural selection. Like if toothed whales are starving and taking in a lot of plankton when they eat other things, this produces a chemical that causes the baleen to grow in the fetuses.

Someone might give reasons why that is not a viable hypothesis, but one could probably think of many such hypotheses if they put their mind to it.

The body hair may come out in cold enough climates. Aren't there other water mammals that have hair? What do they need it for?

ps418

Maybe you recall some "scientists" who thought they were seeing bacteria in a rock from Mars, and they even did DNA tests on them.

What is your source for this claim? As far as I know, there were were never any claims of DNA in the "Martian bacteria." The evidence for a biogenic origin was based on the presence of organic chemicals such as PAH's, magnetite crystals, and morphology. None of this is, or was, presented as definitive evidence for a biogenic origin.

However, I dont think they are bacteria, and neither do most scientists. The most obvious problem is simply their extremely small size -- too small to house the molecular machinerey of a true bacteria.

Patrick

theyeti

hedonologist:

Don't worry about it. Just try to be open-minded and give the evidence a fair chance. I do find the embryological evidence to be quite compeling, but I find the taxonomic, paleontologic, and genetic evidence to be the best. For a good example of the latter, see <a href="http://www.talkorigins.org/faqs/molecular-genetics.html" target="_blank">Plagiarized Errors and Molecular Genetics</a>. And for an overall review of various kinds of evidence, and how they comport with each other, see <a href="http://www.talkorigins.org/faqs/comdesc/" target="_blank">29 Evidences for Macroevolution</a>.

I'm sure that what they're calling teeth and hair really is teeth and hair. Keep in mind that these things are made up of known proteins, and it would be relatively easy to see if the whale hair was the same stuff as other mammalian hair.

I think you may have two different stories mixed-up. The Mars rock was found several years ago to have what looked like bacteria fossils. They did not do DNA analysis because such an ancient sample would almost certainly have had no intact DNA left. And IIRC, what they were looking at wasn't bacteria per se, but rather the mineralized remains of where the bacteria had been. However, some other scientists argued that those structures could have been produced by abiotic processes, and therefore we can't be sure that these were bacteria. We're just going to have to wait for future Mars missions to know for sure.

The other story that I think you're confusing it with was a more recent discovery of living bacteria on a meteorite. They did do DNA anaysis on these suckers, and since they looked suspiciously just like the local boys, it was determined that they were most likely the result of contamination.

In either case, it's important to realize that the scientific community did not just accept these extraordinary claims at face value, but rather conducted further research and demanded further evidence. That is the great strength of science, and you'll be hard pressed to find any creationists who bother to debunk each other's work, no matter how bad it is.

Sure, that's possible, but it does require gobs of additional assumptions. Not the least of which is a creator who can do the miraculous but not get rid of the teeth and hair. This wouldn't be all that difficult -- a human molecular biologist, who could not make a whale, could at least knock out the genes for teeth and hair. Aside from the fact that this doesn't make a whole lot of sense, it is all of the additional assumptions that make us avoid such a theory. In science, you stick with the simple unless you have evidence for the more complex.

If you want, you can read Darwin's own thoughts on that here: <a href="http://www.bbc.co.uk/education/darwin/origin/oos7_3.htm" target="_blank">CHAPTER VII - MISCELLANEOUS OBJECTIONS TO the THEORY OF NATURAL SELECTION</a>. Darwin predicted that a transitional should be found, and since then they have. Here's a more modern account of their evolution: <a href="http://www.otago.ac.nz/geology/features/whales.htm" target="_blank">The Origins and Adaptations of Mysticetes</a>. You're right that powerful evidence of common ancestry does not necessarily provide evidence of natural selection. However, natural selection is the only adaptive mechanism that we see working today, and much of what we see in modern organisms (especially behavior) is consistent with and only with natural selection.

It may that the evidence is incomplete, but it is likely that future studies will fill in the missing pieces, as they have been doing in the past. So until we find another mechanism that has more evidence for it, we will stick with the tried and true. It is important to point out that various creation "theories" (YEC, ID, etc.) have no positive evidence whatsoever.

This could be potentially tested. Just isolate the chemical and give it to some toothed whales. It actually sounds like a form of Lamarckian evolution, which hasn't faired well when put to the test. It seems clear that things do adapt to different niches, but it would seem odd for a creator to make organisms that were not already well adapted. Other than that, unless this theory is somehow distinguishable from natural selection, then we go with the more parsimonious of the two.

Sure, sea lions and otters have hair, but adult whales never do. They are better off without it, because their smooth skin allows them to be streamlined in the water, and their thick layers of blubber take care of the insulation. Keep in mind that sea lions and otters are not exclusively aquatic, and they can not carry around so much blubber with them on land.

The point is that it is totally useless for a whale fetus to have hair, considering the fact that it is always lost before birth. The only coherent explanation for this is that these whales had ancestors that had hair, and the genes for making that hair are still expressed during embryogenesis. This is partly because the mechanism of evolution is not perfect -- it just works on what's around, by changing the development of an existing organism. It makes no sense whatsoever from a design perspective.

theyeti

[ January 02, 2002: Message edited by: theyeti ]</p>