Quote of the Day - 19 July 2005

| 13 Comments

This one comes from my “arrogant things people say in the scientific literature” file.

There is no credible evidence to justify the portrayal on the January 2002 Auk of Microraptor with a thick, white downy coating of putative protofeathers (A. Feduccia pers. obs.). –Alan Feduccia Birds are Dinosaurs: Simple Answer to a Complex Problem The Auk: Vol. 119, No. 4, pp. 1187–1201.

13 Comments

Please elaborate. What is the argument and the evidence in question? Thanks.

The citation is there, and if you want, I’ll be happy to email you a pdf. The broad context of the article is in a longstanding and acrimonious debate over the evolutionary origin of birds. One school of thought, which seems to have pretty widespread support at present, is that the birds are descended from theropod dinosaurs. The other school of thought, which seems to be a minority position, is that birds and dinosaurs are both (separately) descended from the archaeosaurs. Feduccia is a proponent of the “not dinosaur” position, and he is objecting to the cover of a previous issue of the journal, which carried an illustration of a feathered dinosaur. That issue contained a review article which supported the dinosaurs-are-birds position, and which was just a tad critical of Feduccia. (I’ll also be happy to provide that reference on request.)

Ultimately, however, I don’t really think that any of that context is all that important in this case. Citing your own personal observation as the sole support for a statement like that is arrogant. It remains arrogant whether or not Feduccia is correct about the origin of dinosaurs, and it remains arrogant whether or not there is actually evidence that theropod dinosaurs had feathers.

I recently posted a detailed (and scathing) review of the ID-iots’ testimony in Kansas. If you’re interested, check it out on the evolution - creationism forum at the West Virginia Gazette. No registration required.(www.wvgazettemail.com/forums/)

From Rick Prum’s devestating reply:

“After maintaining that feathered theropods were a “myth” or “artistic inventions” (Feduccia 1999a), and stating in his commentary that he cannot find “any credible evidence” of the existence of theropod feathers, Feduccia (2002) completely capitulates and concluded, “There are also asymmetric flight feathers preserved on the wing and near the hind limbs of a dromaeosaurid (Czerkas et al. 2002, Norell et al. 2002).

How does Feduccia integrate those new discoveries into his anti-dinosaur-origin rhetoric? Tellingly, he alters only the smallest necessary details of his scenario, he concedes no contradiction with his decades of previous writings and most of this commentary, and he concludes the same thing. He writes, “we must now carefully consider the possibility that there may have been a number of radiations of secondarily flightless Mesozoic birds that evolved morphologies quite similar to theropod dinosaurs.” That is, Feduccia (2002) hypothesizes that dromaeosaurs are birds that are extraordinarily convergent with theropod dinosaurs, and that birds, including dromaeosaurs, originated from an early archosaurian ancestor and are still not closely linked to theropod dinosaurs.

Feduccia (2002) concluded that the feathered dromaeosaurs should send “all those involved in the debate on bird origins back to the drawing board.” He might prefer to start his argument over, given that he has spent years arguing that dromaeosaurs are completely unlike and unrelated to birds. It is hard to understand how he could find “no credible evidence to justify the portrayal of the January 2002 Auk of Microraptor with a thick, white downy coating of putative protofeathers (A. Feduccia pers. obs.)” on page 1194, and then on page 1196 admit the existence of flight feathers on dromaeosaurs that are Microraptor’s closest relatives. Since my Perspectives, the description of Microraptor gui (Xu et al. 2003) confirms that the portrayal on the January 2002 Auk was actually too conservative (Fig. 1)! Feduccia’s (2002) entire discussions of teeth morphology and replacement, cranial morphology, wrist bone homologies (plus three figures and a table) are completely moot and irrelevant given his acceptance of pennaceous feathers on dromaeosaurs with those serrate teeth, patterns of tooth replacement, cranial morphology, and wrist bones.”

He goes on to beat Feduccia into a bloodier pulp. The full text of Prum 2003 can be found here.

Also, Dr. John Ostrom, a man with more scientific integrity in his little toe than Feduccia has in his entire body, passed away on Saturday.

It was Ostrom who almost single-handedly brought theropod hypotheses out of obscurity.

Prum could have just said, “Citing your own personal observations proves nothing (R. Prum pers. obs.).”

It’s something of a pity that this little beauty was only found in January 2003.

-Schmitt.

M. gui was *described* in January 2003, but it was discovered well before that (in 2001 and 2002).

Since it is probably a synonym of Cryptovolans pauli (which itself is possibly a junior synonym of Microraptor zhaoianus; Senter et al. 2004), this is exactly the critter Feduccia was refering to with the “…asymmetric flight feathers preserved on the wing and near the hind limbs of a dromaeosaurid (Czerkas et al. 2002, Norell et al. 2002)” thing. Norell et al. 2002 published a little blurb on BPM 1 3-13 in Nature, which served as the holotype for Czerkas et al. 2002’s Cryptovolans.

In other words, Feduccia was well aware that Cryptovolans/Microraptor gui was feathered – admitted it even – and *still* said that the feathers drawn on M. zhaoianus, possibly the same *species*, were a fabrication!

The man is as much a scientist studying avian phylogenetics as Behe is a theorist of biochemical evolution. In other words, he’s not.

I guess the basic question is whether there is any evidence of protofeathers on the fossil that the illustration was representing. If the answer is no, then Feduccia is technically correct.

Representations of living organism known only from fossil remains have come under fire repeatedly from creationists (and real scientists as well), in some cases with good cause; scientists understand that illustrations are extrapolations but the non-scientist viewing that illustration may not understand this–so I think scientific illustrators need to be more explicit on just how much of their reconstructions are based strictly on the available evidence, how much of it is reasonable inference, and how much of it is sheer speculation.

I guess the basic question is whether there is any evidence of protofeathers on the fossil that the illustration was representing. If the answer is no, then Feduccia is technically correct.

Only if one forgets what his actual claim was: “There is no credible evidence to justify …”. This is like saying that there’s no credible evidence that a human skeleton was once embedded in flesh if no flesh was found with *that* skeleton.

I think scientific illustrators need to be more explicit on just how much of their reconstructions are based strictly on the available evidence, how much of it is reasonable inference, and how much of it is sheer speculation.

Perhaps so, but none of this goes to whether Feduccia was technically correct – just the opposite.

M. zhaoianus *was* preserved with feathers, BTW. They are most clearly visable along the femur (Xu et al. 2000).

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What, specifically, is horrible about it?

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This page contains a single entry by Mike Dunford published on July 19, 2005 2:40 PM.

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