USC Scientists Uncover Secrets Of Feather Formation

University Of Southern California / ScienceDaily.com ^ | 10/31/2002 | Cheng-Ming Chuong, et al

[forsnax5]

Los Angeles, Oct. 30, 2002 - Scientists from the Keck School of Medicine of the University of Southern California have, for the first time, shown experimentally the steps in the origin and development of feathers, using the techniques of molecular biology. Their findings will have implications for the study of the morphogenesis of various epithelial organs-from hairs to lung tissue to mammary glands-and is already shedding light on the controversy over the evolution of dinosaur scales into avian feathers.

[general_re]

I rejected it as a "valid" use of the experimental results.

Obviously it requires further study, but why is it invalid to infer that from the results for the time being?

[Junior]

The Flat Earth Society is not in any way responsible for the failure of the French to repel the Germans at the Maginot Line during WWII. Nor is the Flat Earth Society responsible for the recent yeti sightings outside the Vatican, or for the unfortunate enslavement of the Nabisco Inc. factory employees by a rogue hamster insurrectionist group. Furthermore, we are not responsible for the loss of one or more of the following, which may possibly occur as the result of exposing one's self to the dogmatic and dangerously subversive statements made within: life, limb, vision, Francois Mitterand, hearing, taste, smell, touch, thumb, Aunt Mildred, citizenship, spleen, bedrock, cloves, I Love Lucy reruns, toaster, pine derby racer, toy duck, antelope, horseradish, prosthetic ankle, double-cheeseburger, tin foil, limestone, watermelon-scented air freshner, sanity, paprika, German to Pig Latin dictionary, dish towel, pet Chihuahua, pogo stick, Golf Digest subscription, floor tile, upper torso or halibut.

[AndrewC]

Obviously it requires further study, but why is it invalid to infer that from the results for the time being?

Politely, that is the difference between a Darwinian and a non-Darwinian, ontogeny repeating phylogeny as a premise.

[general_re]

Some valid arguments have false premises and a true conclusion. Further, since the truth of the conclusion is the issue, and not the premise, and since the truth of the conclusion can be verified or falsified without reference to that particular premise, why is it invalid to take the conclusion as a working hypothesis for further study?

[AndrewC]

Some valid arguments have false premises and a true conclusion.

The conclusion is only a conclusion when mated with a premise, otherwise it is an assertion. Typically, in logic, an argument is a series of connected statements culminating in a proof. A conditional statement is logically always true whenever the premise is false. The statement "If general_re has a billion dollars then general_re is a rich man" does not make "general_re is a rich man".

Study whatever you want.

[PatrickHenry]

Flat Earth Society!

Ah yes. We have many potential members here in our threads. I've often recommended that site, when I thought it appropriate.

[general_re]

The conclusion is only a conclusion when mated with a premise, otherwise it is an assertion.

No, it is a hypothesis for further study.

A conditional statement is logically always true whenever the premise is false. The statement "If general_re has a billion dollars then general_re is a rich man" does not make "general_re is a rich man".

Obfuscation. No such conditional statement exists in this article.

[AndrewC]

No, it is a hypothesis for further study.

An assertion

Obfuscation. No such conditional statement exists in this article.

Incomplete argument. This is all evident to me as pretty silly, so this is my final answer Regis.

[general_re]

I'm not really interested in nomenclature either, but if you wish to castigate the conclusion by implying that it is untruthful as a result of the fact that it is part of a conditional statement, it seems to me that you really ought to be prepared to show the conditional statement that it is a part of....

[tallhappy]

I do not accept this ---Under the general rule of ontogeny repeating phylogeny, downy feather made only of barbs probably appeared before the evolution of feathers with rachides and capable of flight," Chuong says. as necessarily valid.

And that part is, of course, not in the Nature article.

[tallhappy]

Mr Henry, I am waiting to see your summary the new findings in this study?

I'm sure we will all be very appreciative of your contribution.

[VadeRetro]

Ontogeny recapitulating phylogeny is one of those mistaken ideas like that went out like Lamarkism.

Any idea of strict, predictable recapitulation is gone, yes. Still, Evo-Devo lives in the parallelisms of ontogeny and phylogeny.

Amphibians are thought to have arisen come from fish. (In fact, there's a lot of fossil evidence for this.) Baby frogs look like little fish.

Arthropods are thought to have arisen from worms. (There's some scattered fossil evidence for this.) There are many cases of hatchling arthropods (most insects, for instance) resembling worms.

Hatchling horsehoe crabs look like trilobites. Hatchling lampreys look like primitive cephalochordates. Mammalian embryos start out with what looks like a four-part jawbone, but three bones migrate to the ear. That looks an awful lot like a recapitulation of a funny thing in the fossil record where reptilian cynodont therapsid jaws developed a double-joint and the function of the bones beyond the first part seem to have been increasingly coopted for hearing rather than jaw operation. Perhaps you recall that from an earlier thread.

[AndrewC]

but if you wish to castigate the conclusion by implying that it is untruthful

This part is not silly, it is just flat wrong.

Valid is not the same thing as true. I did not imply untruth, I stated I did not accept something as valid in a specific context.

[tallhappy]

...if you wish to castigate the conclusion...

What conclusion are you referring to?

Comments made to the school's PR department are not conclusions.

In the article, the dinosaur issue is addressed only as a speculation. The following is the extent of their conclusion:

Formation of hierarchical branches is the principal feature of feathers17, and is therefore one of the chief issues in the origin and evolution of feathers. On the basis of some fossil evidence it has been proposed that a filamentous integument structure with a major central shaft and notched edges may be the prototype of feathers8-10. According to this model, the rachis would have formed first in evolution, then barbs, and finally barbules. Therefore, the rachis and barbs would be different entities and not interchangable (Fig. 5c). Alternatively, because barbs form first during development, it was proposed that barbs appeared first in integument evolution, and the rachis, a specialized form of fused barbs, appeared later as an evolutionary novelty16, 18. The fact that the barbs and the rachis can be converted experimentally in the laboratory favours the barb to rachis model. Our data suggest that a radially symmetric feather is more primitive than the bilaterally symmetric feather in terms of molecular and developmental mechanisms, and may have been the prototype of feathers (Fig. 5c). Some fossilized primitive skin appendages on Sinornithosaurus also favour this model11. Further modulation of BMP and Shh pathways may have led to the many varieties of feather seen today by regulating the number, shape and size of the rachis, barbs, and barbules1, 17, 30. This work provides evidence for the molecular mechanisms possibly involved in the evolution of feather branching.

Bolded part is their most definitive statement and it only addressed a possible (ie speculative) relation between their molecular findings and a specific evolutionary question involving feather branching.

The study is an excellent analysis of three known developmental modulatory factors (sonic, BMP and noggin)and their roles in feather re-growth after being plucked.

That's all.

Ideas and speculation are fine and that is why they are included in the final paragraph of the discussion.

[VadeRetro]

Amphibians are thought to have arisen come from fish.

Leg thing swim-when-young come from no-legs-swim-all-time.

[general_re]

"Validity" is not contingent upon AndrewC's acceptance of it.

[AndrewC]

"Validity" is not contingent upon AndrewC's acceptance of it.

My, you seem to have discovered logic. But validity is contingent on axioms. And the axioms used in argument are those that are acceptable to both parties.

ax·i·om   Pronunciation Key  (ks-m)
n.

1. A self-evident or universally recognized truth; a maxim: “It is an economic axiom as old as the hills that goods and services can be paid for only with goods and services” (Albert Jay Nock).
2. An established rule, principle, or law.
3. A self-evident principle or one that is accepted as true without proof as the basis for argument; a postulate.

val·id   Pronunciation Key  (vld)
adj.

1. Well grounded; just: a valid objection.
2. Producing the desired results; efficacious: valid methods.
3. Having legal force; effective or binding: a valid title.
4. Logic.
   1. Containing premises from which the conclusion may logically be derived: a valid argument.
   2. Correctly inferred or deduced from a premise: a valid conclusion.

[gore3000]

Uhmm, talking bad about me and not even giving me the courtesy of a ping. Oh well.

We know that legs, arms, mouths are coded by DNA so why should not feathers be coded by DNA also? This is no surprise. What it does show is that we are learning to unravel the DNA code, which is not news either. So what have we found new here? Basically that the coding of the expression of more than three different genes are responsible for the formation of feathers but the article only speaks of three in typical evolutionist reductionist manner.

The experiment also takes a very big shortcut - it uses an animal which already is capable of producing feathers. The experiment therefore does not tell us if these are the only requirements for an animal to produce feathers. If they had manipulated these genes on a lizard, or some reptile and gotten feathers from them, then it could be said that the ability to grow feathers could be easily manipulated from existing species. This experiment clearly does not give such proof. The conclusion which it makes in the first paragraph is therefore totally false:

Scientists from the Keck School of Medicine of USC for the first time have shown experimentally the steps in the origin and development of feathers, using the techniques of molecular biology.

To provide such proof they would have needed to start with a species which did not have feathers. The above conclusion is therefore not warranted by what follows in the article - which is no doubt the reason why you only copied the first paragraph when there was no reason not to copy the entire article.

[gore3000]

But I can't help wondering ... what must it be like, trying desperately to stamp out all new discoveries, all over the world?

Seems to me Patrick that if you were so sure of your theory and the science in the article above you would not have any need for poisoning the well by attacking me even when I am not here. (It is also pretty cowardly and despicable to insult someone behind their backs - which is usual procedure for you).

Since you are sooooooo smart, let's see you refute my post just above this one. My bet it that Placemarker Patrick will have nothing to say except to hurl more irrelevant insults.

[gore3000]

The point I am making is that this will be used, as you indirectly infer, as evidence that supports your viewpoint. If the opposite had occurred, i.e. the rachis forming first, you would have said the same thing.

Quite true, this experiment disproves the claims that evolutionists had been making for a long time and instead "the barbs form first and then fuse to produce a rachis – rather than a rachis forming first and then being sculpted into barbs and barbules." So this experiment, like others we have seen this week disprove claims made by evolutionists about how something happened. It shows another evolutionist prediction falsified. We should not be surprised at this turn of events because evo-science is not science at all. It is just making propositions while sitting in a chair with nothing else to do. It is a purely childish endeavor similar to that engaged in by many on a bull session in a bar.