Fossil ruffles feather evolution theory

[stamenflicker]

Hmm ... down maybe.

Photos of fossils here.

The story itself is no news. There is no non-arbitrary set of morphological criteria which distinguish dromaeosaurs which have feathers from those which don't.

Uncuriously enough, I have never seen this as a problem with dinosaur-bird evolution, and, if you read the article, nor do any of the scientists cited.

Not that either one of us care, what was found was "filamentous integumentary structures." And not that either one of us cares, a scientist recently duplicated this effect in a fossilized dolphin according to his prediction.

Flick

 

[Dr Adequate]

I don't follow you.

 

[stamenflicker]

I don't follow you.

http://www.ncsce.org/PDF_files/feathers/Lingham paper.pdf

from the study:

Titles of articles (Xu et al. 2001; Ji et al. 2001) that proclaim "feathered dinosaurs" actually describe integumentary fibers or feather-like structures, which are not the same as avian feathers, as some of these authors recently noted (Norell et al. 2002). Inconsistencies such as those of another author's support of a "filament to feather" model in one paper (Xu et al. 2001), and the classical "scale to feather" model in another (Zhang and Zhou 2000) cloud one of the important questions in evolutionary biology, the evolution of the avian feather. The subject necessitates that the suggested presence of protofeathers in dinosaurs must be proven or rejected based on incontrovertible evidence, especially given the presence of similar filamentous structures in other groups of fossilized archosaurian and non-archosaurian reptiles (Mayr et al. 2002; Wang et al. 2002; Lingham-Soliar 2001) and mammoths (Kukhareva and Ileragimov 1981).

"The objective of the present study is to consider the popular idea of "protofeathers" in dromaeosaurid dinosaurs by examining our current understanding of dermal and subdermal fibers in vertebrate groups, living and extinct. The debate concerning whether or not birds originate from dinosaurs is not pertinent to the study."

It's worth a gander, but like I said, it's not important for either of us to really engage over. I just object to use of the word feather until more evidence is established.

Flick

 

[Dr Adequate]

So do I, and I was only using the word "down" informally --- I wasn't trying to imply that they were homologous structures.

So far as I know, only dromaeosaur dinosaurs exhibit true feathers.

 

[Dogdoctor]

It is an interesting find, but it was hard to take away anything except: if you find something you believe should have feathers according to theory, but doesn't, just use any one of the possibilities above.

Or you can wait till we know something about it and make a choice based on knowledge rather than preconceived belief.

 

[RSLancastr]

Or you can wait till we know something about it and make a choice based on knowledge rather than preconceived belief.

Spoil-sport.

 

[T'ai Chi]

Or you can wait till we know something about it and make a choice based on knowledge rather than preconceived belief.

Is what they did when they came up with many stories to try to fit the find into what they knew about previous finds based on knowledge or based on belief, or a mix?

 

[Arkan_Wolfshade]

Is what they did when they came up with many stories to try to fit the find into what they knew about previous finds based on knowledge or based on belief, or a mix?

Or, it could be viewed as an excellent example of thinking outside the box, considering the myriad of possibilities to explain the observed phenomenon, or brainstorming.

As I pointed out in the 2nd post in this thread.

 

[Dogdoctor]

Is what they did when they came up with many stories to try to fit the find into what they knew about previous finds based on knowledge or based on belief, or a mix?

They are just considering the possibilities based on current knowledge. Arkan_wolfdude said it also.

 

[T'ai Chi]

Or feathers could have evolved more than once in dinosaurs, cropping up in sister species at different times and places.

How many times? What species? What times? What places?

 

[Skeptic]

Actually, the early tyrannosaur dilong paradoxus was found with feathers.

With a name like that, no wonder it got all the chicks.

 

[UrsulaV]

How many times? What species? What times? What places?

Obviously we don't yet know all there is to know about feather evolution. There's still a lot to learn, a lot of hypotheses to make, and test, and discard if they're found wanting.

In science, the phrase "We don't know yet," is not a sign of weakness. Nor is saying "Here are some possible explanations, but we don't know which it is yet."

But I suspect you get a charge out of yelling "Look! Science changes its mind!" as if this proved something, so don't let me stop you...

 

[Skeptic]

How many times? What species? What times? What places?

Well, IF this particular hypothesis is correct, THEN the answer is that we don't know yet.

Therefore, scientists should (and would) do one of the following:

1). Look for more feathered and/or unfeathered dinosaurs of the right type in an effort to learn more, or

2). Throw up their hands, declare evolution is wrong, and replace it with something like, "God did it" or "It's an unsolvable mystery."

Which one is the right answer?

 

[articulett]

If something isn't what you expected, you try to figure out why it isn't what you expected, you form a number of theories, which you can hopefully find a way to test later.

That seems like quite good science, and common sense to boot, to me. For example--since we're talking about feathers--if I put out birdseed for the birds, and I expect them to show up, and none of them do, I try to figure out why. I form a number of theories--did something happen to the birds? Is this kind of birdseed unappetizing? Is my feeder located somewhere they don't feel safe? and then I test each one, as best I can, until I find the explanation.

Now, bad science would be "I expect it to have feathers, therefore it did," and a clinging to one's pet belief in the face of reality. Not to change in the face of evidence--now that's stupidity.

Tai, I hope you read the answers here such as the one above. What is it that you would prefer--no feathers, therefore an "intelligent designer"? "No feathers, so lets drop everything we've understood so far?" When we discovered the earth was round, we didn't abandon the theory when we didn't understand why we didn't fall off the earth...or why the water in the oceans didn't fall out...we kept exploring and filling in the blanks. Get it?

 

[articulett]

As we all know, any gaps in our knowledge of the fossil record are proof that evolutionary theory is totally false and therefore the Earth was created by god 6000 years ago.

Yes...if any pieces of the puzzle aren't clear than the real answer must be "God went poof!"

 

[articulett]

How many times? What species? What times? What places?

Tai...who is it that you think is qualified to answer these questions...mystics? Or scientists who study the area and are slowly unraveling in the information? Evidence is not the same as a video recording. We can determine a murder was committed and who did it without knowing exactly how or all the details. Not knowing some details is not an excuse for saying "aliens did it". Duh. It's only very recent human history that knows anything at all about dinosaurs and DNA--the holybooks seemed to have left the details out...so we are going to have to crunch the data ourselves--

 

[CFLarsen]

Obviously we don't yet know all there is to know about feather evolution. There's still a lot to learn, a lot of hypotheses to make, and test, and discard if they're found wanting.

In science, the phrase "We don't know yet," is not a sign of weakness. Nor is saying "Here are some possible explanations, but we don't know which it is yet."

But I suspect you get a charge out of yelling "Look! Science changes its mind!" as if this proved something, so don't let me stop you...

Spot on.

It will be ignored by T'ai Chi.