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filthy
SFN Die Hard
USA
14408 Posts |
 Posted - 06/22/2007 : 23:17:24 [Permalink]
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Originally posted by JEROME DA GNOME
Originally posted by Kil
Featherd dinasours don't add up?
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The presentation of the feathered dino in the OP did not add up. The artists pictures were much different than the evidence found(no feathers).
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And what did I say about always taking artist's conceptions with a grain of salt? The fossil didn't have a beak, either; would you have prefered that the drawing showed that as well? In a popular, not a scientific, publication?
Get real, Jerome.
Edit: I went back and checked the Fossil Museum links and they worked just fine.
Further edit: Do you remember our little quiz, that you either didn't bother with or wussed out on? Do you recall my statements on why popular publications run more artist's conceptions than photos of the actual fossils?
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist! 
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| Edited by - filthy on 06/23/2007 00:43:12 |
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filthy
SFN Die Hard
USA
14408 Posts |
Posted - 06/23/2007 : 07:51:15 [Permalink]
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Again, Jerome appears to have let us down. I've been in the office drinking yesterday's coffee for several hours now, and not the first sign of his paper on feathers is on the horizon. His excuse had best be a good one, as I am losing patience.
The really sad part of this is that, whilst researching, he would soon have answered his questions as to the wings of Archaeopteryx and other feathered fossils on his own. He would have learned why they appear as they do.
As can be readily seen in this link, feathers are highly complex. I first became interested in them when writing an article that concerned game bird preparation for the table, and I thought that the article would be enhanced by a description of feather construction. For example, it gave the reason why, when you pluck (that's pluck with a pl!) a duck, it must first be scalded. In ordinary hot water, you can boil that greasy bird until it all but cooks through, and scarcely loosen the damnable feathers. This is due to oils extruded from the skin that make the feathers waterproof. To get the job done quickly, you must put a little detergent of some sort into the water to cut the oils so that it can reach and scald the skin. A little dishwashing detergent is as good as anything.
All birds, modern and archaic, and, as we are learning, the proto-birds and their relatives, have two distinct types of feathers. Next to the skin is a soft thick layer of down. This is for insulating the animal against temperature fluctuations and are visible only in chicks that have not yet fledged, and are still protected by the hen and/or nest. When the chick fledges, they are covered by an outer layer of oiled feathers, laid out rather like the shingles on a roof, that keep them dry. There is no better, natural insulator than this system, and indeed, the very best, cold weather sleeping bags are stuffed with goose down in a water-resistant covering.
Here are a couple of close-ups of feather construction.
As the Wiki link above explains feathers and their construction better than I could, and as Jerome might yet come through for us even as we speak, I will restrict my further remarks to the matter at hand: Archaeopteryx and other feathered fossils.
When an avian dies, it's skin stops producing the oils. If the carcass is not scavenged, the remaining oils will quickly be weathered away, leaving the feathers vulnerable to soaking through. In the right conditions and after quite a short while, the whole bird is an ugly, sodden mass that only slightly resembles what it once was. If the carcass was soon buried, as was Archaeopteryx, the process would continue anyway. The sediments containing the animal would have settled and solidified slowly, and as the oils had been leached out, the wings, along with the rest of the feathers, would eventually fill with fine sand/mud and water. And the process of fossilization would continue until it became what we have today.
So what we end up with is the shape of the wings, the individual feathers discernable only by close examination. It takes a lot of very exacting work to get them even that far into view, and that's why the fossil preparation folks pull down the big bucks (actually, they don't. Many if not most of them are grad students, and that's a phrase that translates into “galley slave.“ Major museums, of course, have professional staff for this sort of thing but they also use interns, a word synonymous with “dogsbody“).
Sinornithosaurus presents us with something of a minor problem. The two existing specimens show them covered with down, and this I find difficult to accept. Oh, I accept that the down is there, right enough; my question is: what happened to the outer feathers? We know that down will soak through easily and it |
"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist!
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JEROME DA GNOME
BANNED
2418 Posts |
 Posted - 06/23/2007 : 12:56:52 [Permalink]
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Filthy said "Jerome, Mr. Filch will be expecting your presence at 1900 hours on Monday evening to begin your latest stint of detention -- an indefinite one, and I shall see to it that he keeps you busy."
I will be needing an address.
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What a man believes upon grossly insufficient evidence is an index into his desires -- desires of which he himself is often unconscious. If a man is offered a fact which goes against his instincts, he will scrutinize it closely, and unless the evidence is overwhelming, he will refuse to believe it. If, on the other hand, he is offered something which affords a reason for acting in accordance to his instincts, he will accept it even on the slightest evidence. The origin of myths is explained in this way. - Bertrand Russell |
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filthy
SFN Die Hard
USA
14408 Posts |
Posted - 06/24/2007 : 01:17:51 [Permalink]
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Originally posted by JEROME DA GNOME
Filthy said "Jerome, Mr. Filch will be expecting your presence at 1900 hours on Monday evening to begin your latest stint of detention -- an indefinite one, and I shall see to it that he keeps you busy."
I will be needing an address.
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Oh, you'll find it, you will find it. Otherwise, Mr. Filch will find you....
Was looking at Wiki for something else and came across an very interesting and detailed page on fossils and fossilization in general. Check it out. Developments in interpretation of the fossil record
See also: History of paleontology
Ever since recorded history began, and probably before, people have found fossils, pieces of rock and minerals which have replaced the remains of biologic organisms or preserved their external form. These fossils, and the totality of their occurrence within the sequence of Earth's rock strata is referred to as the fossil record.
The fossil record was one of the early sources of data relevant to the study of evolution and continues to be relevant to the history of life on Earth. Paleontologists examine the fossil record in order to understand the process of evolution and the way particular species have evolved. Various explanations have been put forth throughout history to explain what fossils are and how they came to be where they were found. Many of these explanations relied on folktales or mythologies. In China the fossil bones of ancient mammals including Homo erectus were often mistaken for “dragon bones” and used as medicine and aphrodisiacs. In the West the presence of fossilized sea creatures high up on mountainsides was seen as proof of the biblical deluge. More scientific views of fossils began to emerge during the Renaissance. For example, Leonardo Da Vinci noticed discrepancies with the use of the biblical flood narrative as an explanation for fossil origins:
"If the Deluge had carried the shells for distances of three and four hundred miles from the sea it would have carried them mixed with various other natural objects all heaped up together; but even at such distances from the sea we see the oysters all together and also the shellfish and the cuttlefish and all the other shells which congregate together, found all together dead; and the solitary shells are found apart from one another as we see them every day on the sea-shores.
And we find oysters together in very large families, among which some may be seen with their shells still joined together, indicating that they were left there by the sea and that they were still living when the strait of Gibraltar was cut through. In the mountains of Parma and Piacenza multitudes of shells and corals with holes may be seen still sticking to the rocks..."
William Smith (1769-1839), an English canal engineer, observed that rocks of different ages (based on the law of superposition) preserved different assemblages of fossils, and that these assemblages succeeded one another in a regular and determinable order. He observed that rocks from distant locations could be correlated based on the fossils they contained. He termed this the principle of faunal succession.
Smith, who preceded Charles Darwin, was unaware of biological evolution and did not know why faunal succession occurred. Biological evolution explains why faunal succession exists: as different organisms evolve, change and go extinct, they leave behind fossils. Faunal succession was one of the chief pieces of evidence cited by Darwin that biological evolution had occurr |
"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist!
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| Edited by - filthy on 06/24/2007 01:22:33 |
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filthy
SFN Die Hard
USA
14408 Posts |
Posted - 06/25/2007 : 04:49:01 [Permalink]
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Let's southern fry a tyrannoasaur; they probably taste like chicken! (We may have gone over this before; I don't recall.)
For the first time, researchers have read what they say is the biological signature of a tyrannosaur — a signature that confirms the increasingly accepted view that modern birds are the descendants of dinosaurs.
The signature doesn't come from studying the shape of the 68 million-year-old dinosaur's fossilized bones, but from analyzing the organic material found inside those bones. It's not DNA — despite what you've seen in movies like "Jurassic Park," that genetic material couldn't be recovered. But researchers say it's the next-best thing: collagen proteins that were isolated using techniques on the very edge of what's possible today.
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So it doesn't necessarily require feathers to to be bird-related. That is assuming that T. rex was not fledged, an assumption that has yet to be verified and may never be. As shown earlier, feathers don't fossilize all that well or often. Tale of a T. rex
The tale of the T. rex began with Horner, back in 2003: He and his team found the tyrannosaur's massive leg bone beneath 1,000 cubic yards of rock at the Hell Creek fossil site in Montana, but had trouble fitting the bone inside their helicopter for the airlift back to the lab.
When they broke the bone into pieces for transport, they were amazed to find that some of the dinosaur's soft tissues appeared to be preserved within. Previously, paleontologists had thought all the tissues of a fossil turned to minerals over the course of millions of years.
After analyzing the tissues under a microscope, Schweitzer reported in 2005 that they looked similar to the cells and blood vessels found in ostrich bones. But at that time, "we could not directly address what that material was made of," she said during a teleconference with journalists this week.
Schweitzer suspected that some of the material was preserved collagen protein — which is the main organic constituent of bone, left behind when the minerals are removed. She said the material looked like collagen, and it reacted like collagen when chicken antibodies were applied to a sample.
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Science in the persona of Dr. Mary Schweitzer, a former grad student of Professor Horner, was applied.
The femur of a Tyrannosaurus rex, found at Montana's
Hell Creek formation, lies within packing material.
Researchers analyzed tissue extracted from within the femur
to determine the dinosaur's protein signature.
I fear that there will be a lot of bones cracked for their collagen traces, rather like fresh marrow bones. So you see, Jerome, there is a bit more to determining bird relationships than the mere presence of feathers. And as the science improves, more will be learned about them with greater ease and accuracy.
Ok, you go catch the rex and I'll heat up the grease. Can't find the hatchet, so here's an axe. Try not to make a mess of it 'cause the neck and wings are the best parts.
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist!
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Xing Xu, Big Bird and the Six Day Shuffle
