Posted on 02/06/2002 5:59:35 AM PST by callisto
SEATTLE, Feb. 6 /U.S. Newswire/ -- A mutant shrimp is being claimed as "a landmark in evolutionary biology" that proves creationists wrong, but it's not. Whatever its implications for creationism, molecular biologist Jonathan Wells, a senior fellow at Discovery Institute in Seattle, Wash., calls the claim "greatly exaggerated," and describes the mutant shrimp as "an evolutionary dead end that tells us little or nothing about how insects might have originated."
A research team headed by William McGinnis at the University of California at San Diego just reported discovering a DNA mutation that produces shrimp without hind legs. Since shrimp normally have lots of legs, and insects have only six, the researchers claim they have discovered the genetic mechanism that caused terrestrial insects to evolve from aquatic ancestors hundreds of millions of years ago. The researchers also claim that this discovery undercuts a primary argument used by creationists against the theory of evolution, because it shows that major mutations do not result in dead animals.
The paper is being released today by the journal Nature.
Wells points out, however, that the mutation reported by McGinnis and his colleagues occurs midway through development, after the embryo is already a shrimp. "The mutation does not transform the embryo into anything like an insect, but only into a disabled shrimp. Whatever produced the first insect would have had to transform the embryo from the very beginning." Wells adds that critics of Darwinism have never claimed that major mutations result in dead animals, but only in animals that are less fit, and thus likely to be eliminated by natural selection. According to Wells, "this report does nothing to refute that criticism."
Wells says he is not surprised that the researchers are making so much of their discovery. "Evidence for the major changes required by evolutionary theory is lacking, so Darwinists often exaggerate the evidence to make the theory seem better supported than it really is."
I don't think it's significant at all. Embryonic development is all about timed sequential expression of genes. These segmentation and homeobox genes are dependent on morphogenetic gradients at precise points in development. Suppression of limb development simply can't occur at the beginning of development, it has to occur at that point in development when the normal sequences for limb development are activated.
Wells, trained as an embryologist, knows better. He seems to imply that genic suppression is not a critical factor in embryogenesis. I suspect he is bothered by the results in these papers.
Since you say that he trained as an embryologist--and even I know that genic suppression is important--what is that he said that made you think that he is minimizing the role of timed genic suppression?
(I am not sure that either one of us has understood the guy.)
I suspect he is bothered by the results in these papers.
Maybe he is. (I'm not, so maybe that's why I didn't assume he was disturbed.)
"The mutation does not transform the embryo into anything like an insect, but only into a disabled shrimp. Whatever produced the first insect would have had to transform the embryo from the very beginning." Wells adds that critics of Darwinism have never claimed that major mutations result in dead animals, but only in animals that are less fit, and thus likely to be eliminated by natural selection. According to Wells, "this report does nothing to refute that criticism."as if mutations which result in altered genic suppression during embryogenesis are not major determinants of organismal bauplan.
His reference to the shrimp's disability is mindful of the theory that bats evolved from rats via a gradual elongation of the medial digit of the forelegs, over zillions of generations, until they finally supported flaps of tissue as the leading edges of two useful wings. The problem with this theory is that the intermediate stucture which would characterize half a zillion of these generations would be neither a useable wing nor a useable foot.
And if natural selection is as powerful an engine as the evolutionists say it is, the half-zillion generations would provide more than ample time for natural selection to kill the crippled animal.
In other words, natural selection tends to prevent bridging from one (existing) species to another (prospective) species via mutation. Vaguely invoking plenty of time and astronomical numbers of one sort or another won't really help. The universe isn't old enough for all of this stuff to have happened. The bat-to-rat difficulty is only one such problem. There are billions more like it.
And the monarch butterfly really is completely inexplicable by standard Darwinian theory. It always will be.
(These problems constitute the reason why Stephen Jay Gould has abandoned standard Darwinian theory in favor of his "hopeful monster" theory. He finally noticed that the creationists' complaints concerning the standard theories of mutation and natural select are crushingly serious.)
Besides, the insurmountable problem concerning the mutation of rat toes to form bat wings also fits the more general complaint by creationists to the effect that mutations are virtually never benefic. They do disable.
I think an engineer would not say concerning the rat-to-bat theory "Well, that's what must have happened." Rather, he would model the scenario of interest using some best-case probabilities and say, "We cannot even say it might have happened. What we need to say is that it definitely didn't happen!"
You are making WAY too much sense to be included in OUR C vs E 'debates'.
BAAAA-HA-HA-HA-hA...
As for faking, the National Geographic hailed a bone structure a Darwinian vindication in 1999 because a dyno had a bird like bone, while this dinosaur bone structure had had a recent chicken bone attached to it. THey never mentioned the error even though it had be widely denounced.
The alternative reading would seem to be that you have given up on standard Darwinianism with gradual evolution--i.e., you are getting close to Gould's "hopeful monster" theory.
You can easily see the similarities in the earlier "proto" form. While scientists are still looking for the actual mechanism that caused the mutation to occur, Stephen Jay Gould conjectured that it is probably one of these three...
Whenever that kind of mindless, idiotic lie is posted, I respond with some of the same kind of "thinking," but in reverse. Look what creationism will do:
IS GOD A COMMUNIST? chapter & verse quotes from the holy bible.
SODOMY AND THE CLERGY. Supernaturalists exposed as pederasts, perverts, boy molesters, rapists, and murderers.
SWAGGART, A FALLEN CREATIONIST Remember this creationist?
And here's the truth about communism and evolution:
Trofim Denisovich Lysenko This guy, not Darwin, Was Stalin's biologist.
The crustacean doesn't have the thorax/abdomen distinction of the insects. It has multiple trunk segments. This trunk segmentation follows Hox gene expression in all arthropods.
Dawkins, true to form, claims that Gould's saltationalism is really, at heart, gradualism on a different scale.
The mutation to remove many of the legs is a simple and common mutation. The first time it happened, it resulted in a lame shrimp, which died off. But it happened quite often, and eventually, it happened to a shrimsect (shrimp in the process of evolving into an insect, that's NOT a scientific term!).
At some point along the shrimsect's evolutionary path, having only six legs--having this common mutation--was more beneficial than having a lot of legs, so the shrimsects with the mutation survived more than those without the mutation. In other words, not every mutation to occur along the path from shrimp to insect was a highly improbable one (although many must have been), some were more common, which makes evolution that much less statistically improbable.
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