Saturday, May 26, 2007

Dinosaur 'feathers' are no such thing

Dinosaur 'feathers' are no such thing, ABC/AFP, 23 May 2007 ...

[Above: The caption says: "The first feathered dinosaur fossil found in China - Sinosauropteryx. The feathers can be seen in the dark line running along the specimen's back," American Museum of Natural History]

The theory that dinosaurs gave rise to birds has been dealt a blow by palaeontologists who have examined critical evidence from a Chinese fossil. The discoverers of the turkey-sized dinosaur Sinosauropteryx say it would have had primitive feathers, supporting the bird-from-dinosaurs theory. But the latest research says these 'proto-feathers' are really frilly structures on the creature's back. Researchers led by South African academic Professor Theagarten Lingham-Soliar at the University of KwaZulu-Natal publish their study in the Proceedings of the Royal Society B.

The debate focuses on Sinosauropteryx, a fossil found in 1994 by a farmer in Liaoning province, northeastern China. This region is a treasure trove of the Early Cretaceous period some 130 million years ago. The long-tailed, meat-eating dinosaur was covered with a down of fibres that its Chinese researchers said were primitive feathers. Although the 'feathers' were clearly not capable of flight, their existence dramatically supported a theory first aired in the 1970s that birds evolved from dinosaurs. As a result, a once-outlandish notion has become the mainstream concept for the ascent of Aves, as birds are classified.

But when researchers examined a recently discovered specimen of Sinosauropteryx, also from Liaoning, they came to very different conclusions. When they examined the fossil under a high-powered microscope, the researchers said the two-branched structures, called rachis with barbs, are really the remains of a frill of collagen fibres that ran down the dinosaur's back from head to tail. "The fibres show a striking similarity to the structure and levels of organisation of dermal collagen," the kind of tough elastic strands found on the skin of sharks and reptiles today, the investigators say. The fibres have an unusual beaded structure, but this most likely was caused by a natural twisting of these strands, and a clumping together caused by dehydration, when the dinosaur died and its tissues started to dry. The tough fibres could have been either a form of armour to protect the small dinosaur from predators, or perhaps had a structural use, by stiffening its tail.

The first known bird is Archaeopteryx, which lived around 150 million years ago. What is missing are the links between Archaeopteryx and other species that would show how it evolved. But the fossil record is frustratingly small and incomplete and this is why debate has been so fierce.

The birds-from-dinosaur theory is based on the idea that small, specialised theropod dinosaurs gained an advantage by developing plant-eating habits, growing feathers to keep warm and taking to the trees for safety. From there, it was a relatively small step for these carnivorous, bipedal dinosaurs with three-toed feet to developing gliding skills and then the ability to fly.

Lingham-Soliar's team does not take issue with the theory itself. But they are dismayed by what they see as a reckless leap to the conclusion that Sinosauropteryx had the all-important proto-feathers, even though this dinosaur was phylogenetically far removed from Archaeopteryx. The evidence in support of the primitive feathers lacked serious investigation, Lingham-Soliar says. "There is not a single close-up representation of the integumental structure alleged to be a proto-feather," Lingham-Soliar says. Given that the evolution of the feather is a pivotal moment in the history of life, he says "scientific rigour is called for". [See also: Dinosaurs link to birds is shot down (The Australian); Feathered dinosaur finding won't fly, say scientists (CBC); Feathers fly over cornerstone fossil (Independent Online); Feathers fly over key evidence in the rise of dino-birds ( & Paleontologists shoot down dinosaur bird theory (

So Sinosauropteryx the "feathered dinosaur" joins the list of "nearly all ... evolutionary stories" that "have now been `debunked':

"It must be significant that nearly all the evolutionary stories I learned as a student, from Trueman's Ostrea/Gryphaea to Carruthers' Zaphrentis delanouei, have now been `debunked'. Similarly, my own experience of more than twenty years looking for evolutionary lineages among the Mesozoic Brachiopoda has proved them equally elusive." (Ager, D.V., 'The nature of the fossil record," Presidential Address delivered 5 March 1976, Proceedings of the Geologists' Association, Vol. 87, No. 2, 1976, p.131-135, p.132)

I remember when the discovery of Sinosauropteryx was first reported in 1998 and, although I had accepted universal common ancestry (but not evolution) , and therefore that birds and reptiles (not necessarily dinosaurs) shared a common ancestor, I have always been sceptical of these Chinese "feathered dinosaur" claims, regarding them as the paleontological equivalent of early astronomers seeing canals on Mars, i.e. what they want to be there. See my comments in previous posts of 24-Sep-05; 25-Oct-05; 01-Mar-06; 16-Mar-06 & 07-May-06.

While no doubt some (if not most) creationist/IDists will hail this as evidence that birds and dinosaurs are not related at all, that will be a misunderstanding of the evidence and what is being claimed by the authors of the Proceedings of the Royal Society B article, which is that these structures are not "protofeathers," and therefore these are not "feathered dinosaurs," and they are not evidence that birds are directly descended from these Chinese theropod dinosaurs (and presumably any theropod dinosaurs, if not any dinosaurs at all), but being reptiles they still share a common ancestor with birds.

Nevertheless, this is going to be very embarrassing for those Darwinists like Mark Norell who have pushed these "feathered dinosaur" claims in the media; and the gullible journalists who accepted those claims uncritically, and will further cause the public to distrust confident-sounding claims about evolution!

It will also probably cause a major shake-up in paleontology because a lot of time, energy and, above all prestige, has been invested in this Chinese "feathered dinosaur" theory, despite the obvious fact that, as the late Ernst Mayr (who was an ornithologist) pointed out, the "bipedal dinosaurs that are most birdlike occurred in the later Cretaceous, some 70-100 million years ago, while Archaeopteryx, the oldest known fossil bird, lived 145 million years ago" (i.e. ~45 million years earlier) and "Archaeopteryx has so many advanced avian characters that the origin of birds must be placed considerably earlier than the late Jurassic, perhaps in the Triassic":

"The greatest current controversy in phylogeny will perhaps be settled by invoking parallelophyly; it concerns the origin of birds. There is no argument over the conclusion that birds derived from the archosaurian lineage of the diapsid reptiles. But when this happened is the argument. As far back as the 1860s, T.H. Huxley called attention to the remarkable similarity of the avian skeleton to that of certain reptiles and concluded that the birds had descended from dinosaurs. Later, other authors postulated a much earlier origin, but recently the dinosaur origin has been proclaimed by the cladists with such vigor that at present it seems to be the most widely accepted explanation of the origin of birds. Indeed, the similarity of the pelvis and legs between birds and certain bipedal dinosaurs is astonishingly close ... However, the arguments of their opponents are also very persuasive. The fossil chronology seems to be in conflict with the dinosaur theory. The particular bipedal dinosaurs that are most birdlike occurred in the later Cretaceous, some 70-100 million years ago, while Archaeopteryx, the oldest known fossil bird, lived 145 million years ago. Archaeopteryx has so many advanced avian characters that the origin of birds must be placed considerably earlier than the late Jurassic, perhaps in the Triassic, but no birdlike dinosaurs are known from that period. Furthermore, the digits in the dinosaurian hand are 2, 3, 4 while in the avian hand they are l, 2, 3. Also, the anterior extremities of the birdlike dinosaurs are very much reduced and in no way preadapted to become wings. It is quite inconceivable how they could have possibly shifted to flight. These are only a few of the numerous facts in conflict with a Cretaceous origin of birds from a dinosaurian ancestry. The argument will probably not be fully settled until more Triassic fossils are found." (Mayr, E.W., "What Evolution Is," Basic Books: New York NY, 2001, pp.227-227. Emphasis original).

The problem, as ID biologist Jonathan Wells pointed out in his book, "Icons of Evolution" (2000), is the over-emphasis on "cladistics" where "character comparisons take precedence over everything else" and "The order in which animals appear in the fossil record also becomes secondary or irrelevant":

"In cladistics, character comparisons take precedence over everything else. `The anatomical details or characters,' writes paleontologist Pat Shipman, `constitute the evidence, which ultimately adds up to a certainty approaching proof' [Shipman, P., "Taking Wing: Archaeopteryx and the Evolution of Bird Flight," Simon & Schuster: New York NY, 1998, p.33] of evolutionary relationships. Other factors are discounted. For example, physical difficulties inherent in the `ground up' theory of the origin of flight are unimportant; what matters is that birds are anatomically more similar to two-legged running dinosaurs than to four-legged climbing reptiles. To a `cladist' (someone who uses the cladistic method), the debate over the origin of flight is secondary, if not irrelevant. The order in which animals appear in the fossil record also becomes secondary or irrelevant. If evolutionary relationships are inferred solely on the basis of character comparisons, an animal can be the descendant of another even if the supposed ancestor doesn't appear until millions of years later. The fossil record is simply re-arranged to fit the results of cladistic analysis. ... Applying cladistics to the evolution of birds leads to the conclusion that the ancestor of Archaeopteryx was a two-legged dinosaur. Ironically, once cladistics took over and similarity became the only criterion for relationships, paleontologists found that the most likely candidates for the ancestor of Archaeopteryx lived tens of millions of years later. .... According to cladists, the animals with the right features were bird-like dinosaurs that lived in the Cretaceous period, long after Archaeopteryx had become extinct. But then, in order to make bird-like dinosaurs the ancestors of birds, the fossil evidence must be re-arranged. ... The obvious objection that an animal cannot be older than its ancestor is discounted by assuming that the ancestral form must have been there before its descendant, but its fossil remains cannot be found. In other words, advocates of cladistics cite the imperfection of the geological record the very same reason Darwin gave for the troubling absence of transitional forms. As a result, however, the gaps in the fossil record become more pronounced than ever before. Immense stretches of time are left with no fossil evidence to support cladistic phylogenies. Critics of cladistic methodology argue that the features on which cladists base their analyses may have evolved independently, and don't necessarily point to common ancestry. Critics also argue that although the fossil record is incomplete, it is not as incomplete as cladistic analyses imply. Cladists disagree, and the result has been a raging controversy." (Wells, J., "Icons of Evolution: Science or Myth?: Why Much of What We Teach About Evolution is Wrong," Regnery: Washington DC, 2000, pp.119-120. Emphasis in original)

Then the problem in turn for cladistics is convergence or homoplasy, "when characters are similar, but are not derived from a common ancestor." If such homoplastic characters are fed into a cladistic computer system, the cladogram generated will look authoritative but it will in fact be another case of GIGO (garbage-in-garbage-out)! But if characters can be so similar that they fool some of the world's leading paleontologists, yet that close similarity may not be due to direct inheritance from a common ancestor, then how could evolutionists ever be sure that any one fossil is directly descended from another?

So now that these Chinese "feathered dinosaurs" (and presumably all theropod dinosaurs, if not all dinosaurs) are not ancestral to birds, apart from correcting all those museum exhibits, books, journals, articles and websites, paleontologists will have to look again for "the origin of birds ... considerably earlier than the late Jurassic [~160-145 mya], perhaps in the Triassic [~250-200 mya], but no birdlike dinosaurs are known from that period!"

That is, if Darwinism is true, and the first bird was not supernaturally progressively mediately created, in a (or a series of) "leap[s] across genetic hyperspace":

"1. Could the human eye have arisen directly from no eye at all, in single step? ... The answer to Question 1 is clearly a decisive no [naturalistically] . The odds against a `yes' answer for questions like Question 1 are many billions of times greater than the number of atoms in the universe. It would need a gigantic and vanishingly improbable leap across genetic hyperspace." (Dawkins, R., "The Blind Watchmaker," W.W. Norton & Co: New York NY, 1986, p.77. Emphasis original).

"There is another mathematical space filled, not with nine-gened biomorphs but with flesh and blood animals made of billions of cells, each containing tens of thousands of genes. This is not biomorph space but real genetic space. The actual animals that have ever lived on Earth are a tiny subset of the theoretical animals that could exist. These real animals are the products of a very small number of evolutionary trajectories through genetic space. The vast majority of theoretical trajectories through animal space give rise to impossible monsters. Real animals are dotted around here and there among the hypothetical monsters, each perched in its own unique place in genetic hyperspace. Each real animal is surrounded by a little cluster of neighbours, most of whom have never existed, but a few of whom are its ancestors, its descendants and its cousins. Sitting somewhere in this huge mathematical space are humans and hyenas, amoebas and aardvarks, flatworms and squids, dodos and dinosaurs. In theory, if we were skilled enough at genetic engineering, we could move from any point in animal space to any other point. From any starting point we could move through the maze in such a way as to recreate the dodo, the tyrannosaur and trilobites. If only we knew which genes to tinker with, which bits of chromosome to duplicate, invert or delete. I doubt if we shall ever know enough to do it, but these dear dead creatures are lurking there forever in their private corners of that huge genetic hypervolume, waiting to be found if we but had the knowledge to navigate the right course through the maze." (Dawkins, 1986, p.73) .

from a reptilian (or even a dinosaurian) ancestor!

Stephen E. Jones, BSc. (Biology).

Leviticus 9:23-24. 23Moses and Aaron then went into the Tent of Meeting. When they came out, they blessed the people; and the glory of the LORD appeared to all the people. 24Fire came out from the presence of the LORD and consumed the burnt offering and the fat portions on the altar. And when all the people saw it, they shouted for joy and fell facedown.

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