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Feduccia et al. (2005) Critique



The BAND movement simply refuses to die, invigorated as it is by its transformation into MANIAC. It seems like just yesterday that I shot down Martin's latest publication (http://dml.cmnh.org/2005May/msg00317.html), now I get to do the same for Feduccia's. Well, technically Lingham-Soliar and Hinchcliffe are coauthors, but I mostly refer to Feduccia himself below for simplification.

Feduccia, A., Lingham-Soliar, T., and Hinchliffe, J.R. (2005). Do feathered dinosaurs exist? Testing the hypothesis on neontological and paleontological evidence. J. Morphology (in press).


The article starts out with an introduction full of fun inaccuracy.

"Much of the heated debate that ensued has been hyperbolic, as everyone agrees that birds are derived from within the archosaurian assemblage: whether birds are derived from ?dinosaurs? depends largely on how one defines the Dinosauromorpha (Feduccia, 1999a)."
Or more accurately, how one defines Dinosauria. Ironically, Martin (2004) derives birds from outside Archosauria (unless you define Archosauria to include birds, which though common, is against Phylocode suggestions).


"At the extreme, Archaeopteryx became an earthbound, predatory dromaeosaur that could not fly (Bakker, 1975), despite its obvious arboreal and flight capabilities and near absence of dromaeosaurid anatomy, lacking salient features including a pedal 2nd sickle claw and stiffened ?ramphorhynchoid-like? tail."
I'm sure Paul would have much to say about a claim Archaeopteryx has a near absence of dromaeosaur anatomy. Because basal dromaeosaurs would have to have all the synapomorphies of dromaeosaurids, right?


"Instead of an early bird origin and a likely and facile trees-down flight origin, birds evolved later in time, directly from highly specialized theropods, and would have to fight gravity to gain ascendancy by a biophysically untenable cursorial origin (Feduccia, 1999a; Long et al., 2003)."
It's our good friend, the False Dichotomy of Flight Origins.


"The latest theories involve a shift from one to three locomotor modules (Gatesy and Dial, 1996), and a truly bizarre model based on
highly derived hill-running quail, running up tree trunks (Dial, 2003)."
Because deriving birds from avicephalans with one locomotor module is somehow different? And what a detailed criticism of WAIR! It's bizarre, it must not be true.


And only after a half page of criticisms of the ground-up origin for flight do we see this-
"Finally, the discovery of arboreal Lower Cretaceous flying, four-winged microraptors with pennaceous feathers, thought to be theropod dinosaurs (dromaeosaurs), appears to have validated an arboreal origin of flight regardless of the ancestry (Zhou, 2004)."
Well, looks like it was all unecessary after all...


"It would not tax the imagination to engender a long list of obstacles for the now dominant model of a theropod origin of birds, including, but not limited to:"
Ooh. I'm _sure_ each and every one of these will be a deathblow to BAD.


"the fact that early theropods (e.g., Triassic Herrerasaurus) are highly specialized obligate bipeds (with arms reduced to 1/2 the length of the hindlimbs);"
There goes all of our cladograms deriving quadrupedal birds from herrerasaurids. :( And it was such a good hypothesis too...


"the fact that the stratigraphic sequence of bird-like theropods has been almost the reversal of the expected evolutionary sequence
leading to birds;"
Wait, I thought Feduccia _knew_ about the Yixian Formation.


"the fact that the earliest described ?feathered dinosaur? is the unbird-like compsognathid Sinosauropteryx, devoid of any preserved structures that can be shown to be feather-like;"
We all know just how important the order of discovery is to the validity of a hypothesis. I'm sure Feduccia would have no problem at all had Sinornithosaurus been discovered first. Even Sinosauropteryx (or Herrerasaurus for that matter) is more birdlike than Longisquama. And even if Sinosauropteryx wasn't feathered, it woudn't matter. The fact Tyrannosaurus and Allosaurus aren't feathered doesn't bother BAD, why would Sinosauropteryx?


"the fact that any downy-like integumentary covering in a terrestrial theropod would be maladaptive;"
Ironically like the creationists he claims BADists are helping, Feduccia can examine all possible adaptive pathways and know they won't work.


"the fact that flight feathers arranged precisely on the hand as in modern birds are present in microraptors and the basal oviraptosaur
Caudipteryx;"
This is, without doubt, the strongest criticism of BAD I have EVER seen. Let's give up now, people.


"the fact that many of the derived characters or synapomorphies linking birds and theropods are in question, including notably but not limited to: the sliding lower jaw joint of theropods (absent in birds), the theropod ascending process of the astragalus (distinctive from the avian pretibial bone), and the digital mismatch (1,2,3 theropod vs. 2,3,4 bird hand), etc., to mention a few."
Feduccia can ignore Shenzhouraptor's ascending process as well as Martin can, and the implication for oviraptorosaurs and deinonychosaurs having ascending processes. Ironically, Zhou et al. (2005) just described the presence of an intramandibular joint in Eoenantiornis. And there's the homeotic digital frameshift, which is addressed later in the article...


Well, that WAS fun. But now to the meat of the paper. "Here we focus on two paramount issues." It's naive falsification again. MANIAC's think that if they disprove a few homologies between dinosaurs and birds, the entire relationship disintegrates. If only someone would tell them that the dinosaur-bird link is based on hundreds of characters, and that each of these would need to be refuted or equaled by an alternative ancestor to make any difference. If only someone had written such an article. Perhaps a leading theropod researcher (Makovicky) and a leading paleornithologist (Dyke) at the 1999 Ostrom Symposium. But alas, that's only wishful thinking (p.s., see pages 501-509 in the Ostrom Symposium volume).


Topic 1- Lingham-Soliar tries to refute non-maniraptoran feathers.
Now I haven't even read this section yet, but I can state right now that it has no influence on bird origins at all. Let's say Sinosauropteryx, Dilong, Beipiaosaurus and Sinornithosaurus actually do preserve collagen instead of feathers. This tells us nothing about what their actual integument was, plus we have Shuvuuia's feathers to bring the character to the base of Maniraptora or Maniraptoriformes anyway. But even if they were somehow shown to lack feathers, it wouldn't matter. Just as scaled carnosaurs and tyrannosaurids don't harm bird origins, scaled basal coelurosaurs wouldn't either. And whatever he says about Sinornithosaurus hurts him as much as us, since we both agree it was closely related to birds. But let's see what he has to say.


First, I want to give Lingham-Soliar credit. He uses seven reptilian specimens (six of which are terrestrial, including a crocodile and a chicken), as examples of collagen fibers. I'm far more likely to trust this than dolphins, ichthyosaurs or seasnake fins.

"Currie and Chen (2001, p. 1723) speculated that the integumentary structures ?probably covered most of the body of living Sinosauropteryx? despite the occurrence of only coronal preservations in all specimens examined. Given the description of only
coronal preservations by the authors, the comment by Norell and Xu (2005, p. 292) that ?careful observation of the Sinosauropteryx specimens shows [my italics] that the integumentary fibers were distributed over the entire body and were not just a Mohawk-like crest (Currie and Chen, 2001)? is misleading in its misrepresentation of the cited data."
Or perhaps it's Lingham-Soliar who is misleading, as he apparently missed these statements from Currie and Chen (2001)- "There are small patches on the side of the skull behind the quadrate and paroccipital process, anterior to the articular, and below the back of the mandible (Fig. 12a). ... There is a small patch lateral to the left ribs and several areas on the left side of the tail lateral to the vertebrae."


Lingham-Soliar responds to the issues raised by Currie and Chen (2001) which supported a feather identity for its structures.
1. The fact the feathers are distanced from the skeleton by the rough amount of flesh that would be expected in each area.
Lingham-Soliar's basic argument here is that if collagen fibers were dispersed outside the body (which sometimes happens in ichthyosaurs), they might decompose where overlapping flesh too. Sounds reasonable enough.
2. Birds showing preserved feathers are unquestioned by BANDits. Here, Lingham-Soliar seems to forget science. His reply is that birds are expected to have feathers, so don't require questioning. Obviously, if what we accept as bird feathers has the same collagen characteristics as Sinosauropteryx's feathers do, then either the birds are also preserving collagen or the suggested collagen characters are unreliable.
3. The barbs are wavy, implying a pliable texture. Lingham-Soliar's photo of wavy snake collagen effectively refutes this evidence.
4. The dark edges imply a hollow structure. He shows a photo of ichthyosaur collagen which has similar dark edges, and explains how it can be explained via mineralization from the inside out. I'll agree this is a valid alternative explanation.
5. Thinner filaments (barbs) are found distal to thicker ones (rachis). His photo of dolphin collagen which shows this is also fairly convincing.


Lingham-Soliar asks regarding Dilong's feathers, "While the authors interpret the ?V? or ?Y? shapes made by the fibers as a simple branching pattern, it would be interesting to know how they would interpret all the ?+? or ?X? shapes present."
As barbs crossing one another. There's a handy series of photos in figure 6 of match sticks dropped in a pile, to illustrate how they form a variety of angles with each other at random. It might just be the silliest photograph I've seen in a dinosaur paper.


When it comes to Sinornithosaurus' holotype, it's hard to see where Lingham-Soliar is going. No doubt affecting this is the fact the figure is hopelessly blurry. He claims the base of the illustrated tuft of filaments is actually an eroded area with filaments that run diagonal to the main tuft. Perhaps true (I can't evaluate the figure), but Xu et al. (2001) mentioned several instances of tufts. Lingham-Soliar argues a case of filaments branching from a central one is due to the "laws of chance", which is fine, but again Xu et al. stated several of these occurances were present. He also states that integumentary structures are found throughout the substrate, including fainter (more eroded?) ones covering almost the entire surface. I don't see how this argues against them being feathers. Given the quality of Lingham-Soliar's figures for Sinornithosaurus, I found his statement "... the conclusions arrived at by Xu et al. (2001) are not only seriously flawed and technically unsound but misleading to the reader both by the extremely poor quality of their figures (uninformative in vital respects) ..." hilariously ironic.

He dismisses NGMC 91 (cf. Sinornithosaurus; Dave) merely because herringbone patterns are also seen in his new Psittacosaurus specimen. While true, the NGMC 91 integument bears a closer resemblence to feathers.

"Caudipteryx has, in our view, been fairly conclusively shown to be a secondarily flightless bird."
It's a good thing your view ignores Ji et al. (1998), Sereno (1999), Xu et al. (1999, 2000), Holtz (2001), Rauhut (2003), Norell et al. (2001) and modifications, Holtz et al. (2004), Senter et al. (2004), Zhou and Wang (2000), Dyke and Norell (2005), Christiansen and Bonde (2002) and almost everyone else.
"Furthermore, exhaustive cladistic analyses (Maryanska et al., 2002), place Caudipteryx and other taxa that belong to Oviraptorosauria as flightless birds."
Yet the first nine papers listed above contain such analyses that place oviraptorosaurs basal to Archaeopteryx. And Maryanska et al. (2002) was highly flawed.



Topic 2- Feduccia and Lingham-Soliar describe their Psittacosaurus and Pelecanimimus discoveries.


This Psittacosaurus is pretty amazing. A complete specimen with filaments preserved inside the ribs. Often preserved crossing one another, they do form herringbone patterns sometimes. They claim some filaments appear beaded and curved, which occurs in degraded collagen. Are these feathers? No, as we have the very well preserved quilled specimen that indicates psittacosaurs were fully scaled, including over the rib region. Could this be a feathered juvenile of a scaled adult? It is half the size of the quilled specimen (and doesn't preserve quills, though this could be taphonomic). So I can't dismiss that possibility. Also of note is that they state "We cannot comment on whether or not keratin may decompose in a similar way to collagen, but certainly the beaded condition is not precluded if rippling of the keratin layer, perhaps as a consequence of dehydration, takes place during decomposition." Regardless, I find a collagen identity plausible. What the fibers look like to me is what Czerkas and Yuan (2002) called feathers in Scansoriopteryx. I wouldn't be surprised if the latter were collagen (if the Psittacosaurus structures are). Maybe the less similar structures in the Sinornithosaurus holotype are too. It doesn't matter, since Microraptor and NGMC 91 clearly preserve body feathers. I still doubt Sinosauropteryx's and Beipiaosaurus' feathers are collagen because they resemble maniraptoran feathers more than Psittacosaurus' structures, they are very elongate in places I'd expect feathers instead of lots of collagen (Sinosauropteryx's tail, Beipiaosaurus' arm), and Shuvuuia shows maniraptoriformes had feathers anyway. As for Dilong, I'm more equivocal. The authors also do not discount basal coelurosaurs' structures being something besides collagen, like turkey beard bristle homologs. Sounds possible. I appreciated their comments about keeping an open mind and performing further research into basal coelurosaur integument.

Pelecanimimus is less convincing. There are supposedly overlapping scales on the forearm, some with "fingerlike projections". These are photographed (though not in relation to any bones), but they don't immediately strike me as scales. At least not dinosaur scales. They seem to be diamond-shaped, like you'd find on a gar. Maybe Pelecanimimus did have rhomboid overlapping arm scales. I can't help but think of Santanaraptor though (which Feduccia et al. mention as an unnamed theropod), which the authors describe as having "a thin epidermis, formed mostly by irregular quadrangles bordered by deep grooves in a criss-cross pattern." Amusingly, if the authors are right, this destroys their prior argument dinosaurs lacked overlapping scales, so couldn't evolve feathers (under Maderson's outdated developmental scheme).

A few other comments on this section. The authors attempt to use Scipionyx's absent feathers as some sort of evidence, despite the fact no epidermal material of any sort was preserved. They go almost out of the way to call Psittacosaurus an ornithopod, stating this twelve times. Suppose it's no worse than Martin (2004) calling Coelophysis a coelurosaur. MANIAC's are stuck in the 70's when it comes to dinosaur phylogeny. They continue to use pterofuzz's existance as some sort of mark against dinosaur feathers being real, perhaps unaware the pterosaur researching community has accepted for decades that filamentous integument covers the creatures. Also supposedly problematic is Beipiaosaurus' feathers, as therizinosaurs are "a taxonomic enigma, but which (have) the lanceolate teeth of a prosauropod (Feduccia, 2002)." Groan. Like I said, stuck in the 70's. Or in this case, late 80's to early 90's. They could at least have cited a paper which actually examined segnosaurs and concluded they were prosauropod-like, based partly on their teeth, like Paul (1984). Finally, they mention Compsognathus, but don't mention the fact body feathers are unpreserved in most Archaeopteryx specimens or that Ostrom (1978) actually did find possible filaments (http://dml.cmnh.org/2003Apr/msg00202.html). There is a short followup that says because downy chicks die when wet for several days, downy dinosaurs would too. Prum's stage I feather is basically a hair, and mammals aren't dying in wet environments. Actual down is not equivalent to a stage II feather, since down has "elongate barbules with nodal prongs that interact among barbs to form disorderly tangles that produce a large volume." (Prume, 1999) Barbules didn't develop until stage III, and thus the water-retaining properties of feathers weren't present until the closed pennaceous vane allowed exterior feathers to waterproof the animal.


Topic 3- Feduccia and Hinchcliffe examine digital homology.

"There appears to be little question that the hand of theropods represents D1,2,3, and in fact it has been suggested that it is the primary synapomorphy for ?dinosaurs? (Fig. 17; Feduccia, 2002)."
"Thus, the postaxial reduction of digits 4 and 5 may be the most salient synapomorphy for the monophyly of Dinosauria (Feduccia, 2002:1190)."
Funny, because I could have sworn Bakker and Galton (1972), Gauthier and Padian (1985), Gauthier (1986), Benton (1990) and Novas (1992) came up with this dinosaurian synapomorphy one to three decades before Feduccia did, and as part of in depth analyses too, as opposed to a passing comment.


"Note that the longest finger in primitive theropods [Herrerasaurus is shown] is not the middle finger, as in Archaeopteryx (and birds), and dromaeosaurs (microsaurs, Deinonychus, etc.), and most tetrapods including man, but finger 3, which is what one would expect."
I'll pass on insulting the microsaur comment and focus on reminding Feduccia that all theropods except Herrerasaurus and Eoraptor have the second finger the longest, from Coelophysis to Allosaurus to Sinosauropteryx to Pelecanimimus. Well, not Ornithomimus, scansoriopterygids or alvarezsaurids, but they're clearly irrelevent.


"In Cretaceous enantiornithine birds, phalangeal formulae are varied: P2,3,3 (Eoalulavis), P2,3,1 (Concornis), and P2,3,2 (Protopteryx)."
Except that Eoalulavis has a 2-3-1 formula. Maybe they meant Jibeinia.


Feduccia goes about arguing bird digits are II-III-IV, which is apparently true. He states several objections to the frameshift hypothesis. It would have no adaptive advantage (see Vargas and Fallon, 2005 for a discussion of neutral mutations). Most homeotic shfts would affect the feet too (most is not all). Theropods would have had to possess a condensation IV (easy enough, as taxa as derived as Coelurus and Tanycolagreus still had a rudimentary digit IV). The distal carpals would have to shift posteriorly (interestingly, distal carpal I+2 does shift from primarily on digit I to primarily on digit II during bird evolution; amusing, Zhou and Martin used this difference in semilunate position as evidence against birds being maniraptorans years ago). There is no known mechanism that simultaneously affects four digit condensations (regardless, it seems to have occurred in the three-toed skink- Wagner, 2005). It would be the only known shift of its type (perhaps not true given the three-toed skink).

"In order for there to be a pentadactyl ground plan one would have to invoke a basal archosaur that had an undifferentiated hand, a form such as the Triassic Lagosuchus, considered by many to be close to the ancestry of dinosaurs (Feduccia, 1999a), and whether or not it is considered a ?dinosaur? is anyone?s opinion."
Feduccia's taking credit for placing Lagosuchus close to the ancestry of Dinosauria now? And here I thought that credit went to Romer (1971), when it was first described. In fact, basically everyone who's examined the situation has believed it, with major works like Bonaparte (1975), Novas (1989) and Sereno and Arcucci (1994) providing the most extensive reasoning.
As for whether Lagosuchus is a dinosaur, WHY won't Feduccia notice there's a near universal consensus among dinosaur researchers as to what a dinosaur is? The only dissenters of non-dinosaurian Marasuchus are Olshevsky, who has a basal dinosaur phylogeny nobody follows, and Kischlat (2002), who hasn't published his reasoning yet.


Even Feduccia et al. conclude with the unexpectedly non-dismissive statement "At present, there seem to be too many
unknowns to accept the ?Frame Shift? as a well established and convincing theory." I'd agree somewhat. It's not well established. There's much work to do establishing mechanisms and studying potentially similar cases. I highly recommend Vargas and Fallon (2005) and Wagner (2005) for recent discussions of avian digital homology.



Topic 4- The avian identity of Caudipteryx.

"That phylogenetics has become an assumption laden field is best illustrated by the insistence that the avian wing of Caudipteryx, with its intricate detailed flight anatomy and avian arrangement of primary and secondary feathers on the hand and arm (Fig. 26), evolved in a context other than flight (Sereno, 1999; Norell and Xu, 2004)."
A _prediction_ laden field. And that's a good thing.


"According to recent paleontological theory, everything related to the lineage of avian origins must be developing flight from the ground up and all aerodynamic adaptations, regardless of their aerodynamic precision, must have evolved in a context other than flight, as preadaptations."
How soon he forgets his statement in the intro about how the discovery of Microraptor makes the theropod = ground-up correlation moot.


"Caudipteryx has a manual digital formula of 2,3,2, as in advanced birds, an avian hand, an avian-like skull with a ventral foramen magnum and avian-like teeth, and a partially reversed hallux, compelling Zhou et al. (2000, p. 243) to note that ?the ancestor of Caudipteryx had probably possessed the arboreal capability.?
The teeth have nothing to do with flight, the hallux is unreversed (Middleton, 2003), the foramen magnum orientation cannot be established (Geist and Feduccia, 2000 argued this based on a disarticulated exoccipital fragment), and besides the reduced third digit, the hand is largely similar to basal coelurosaurs. Finally, kiwis are an example of birds that reduced their digits while flightless, so the reduced third digit doesn't argue for neoflightlessness either.


"Despite the fact that the cladistic analysis of Maryanska et al. (2002) utilized 195 coded characters and is ?unassailable from the
standpoint of strict cladistic orthodoxy? (Olson, 2002, p. 1204), Dyke and Norell (2005), noted for strict adherence to cladistic methodology, cannot accept that Caudipteryx could be a flightless bird."
Oh yes, unassailable. Why, I couldn't find a fault with that analysis if I tried. Certainly not the exclusion of any ornithurines except Confucusornis. Nor the exclusion of troodontids or any dromaeosaurs more similar to birds than Deinonychus and Velociraptor. Yessiree, unassailable.
"Paleontologists are still trying to return Caudipteryx to theropod status (Dyke and Norell, 2005), but Maryanska et al.?s (2002) exhaustive cladistic analysis remains undisputed and cannot be breached."
Amazing! Especially since Feduccia himself disputes it (it derives maniraptorans from theropods, after all), as do all four more recent phylogenetic analyses I listed above (Rauhut, 2003; Holtz et al., 2004; the Theropod Working Group analyses; Senter et al., 2004). If only all our BAD cladistic analyses were as unbreachable as Maryanska et al.'s, the MANIAC's would be doomed.
Furthermore, Dyke and Norell never said Caudipteryx couldn't be neoflightless, they merely refuted Jones et al.'s (2000) conclusion Caudipteryx plots with birds instead of theropods when measured for hindlimb/trunk proportions.


"The preponderance of evidence points to Caudipteryx being a flightless bird (Feduccia, 1999a), but one can only ponder how the postcranial remains of any ratite would be identified if recovered from the Early Cretaceous of China."
As a neornithine at least, as it'd have lots of heterocoelous cervicals, lots of sacral vertebrae, a short pygostyled tail, strut-like coracoid, fused sternum, reduced manual unguals, flattened manual phalanx II-1, no pubic symphysis or foot, a highly retroverted pubis, trochanteric crest, hypotarsus, etc., etc..


Feduccia wastes this whole section trying (poorly) to show Caudipteryx was neoflightless, when it wouldn't help their case on bit. No mention is made of Paul (2002), who finds it to be both neoflightless and a dinosaur. No attempt to refute Dyke and Norell's (2005) finding is made, except to describe Maryanska et al.'s study (which didn't even address the same issue) as invincible. I can only guess the latter is a setup for BADists, who will then note problems with the study, only to have Feduccia retort "see, your cladistics are meaningless; if you can deny the accuracy of Maryanska et al., we can deny the accuracy of any and all analyses too." The statements are just too stupid and out-of-character to be serious.


Topic 5- Lifestyle of Confuciusornis

Feduccia argues Chiappe et al. (1999) and Padian and Chiappe (1998) made Confuciusornis too terrestrial. Their issue with the latter publication is apparently the cover illustration of the magazine (in case you're wondering, the large technical article which this Scientific American one was based on didn't mention Confuciusornis' behavior or abilities at all). He presents reasons Confuciusornis was a decent flier, but nobody disputed that. Just because it was restored standing on the ground in the illustration and in Chiappe et al.'s skeletal reconstruction does not mean they believe it was "an earthbound predator". Indeed, the latter authors state it had more advanced flight-related characters than Archaeopteryx and could take off from the ground. So Feduccia's battling a strawman when he says "Chiappe et al. (1999) argue not only that Confuciusornis was terrestrial, but that it was not arboreal, when even the most casual analysis suggests that it was a competent flier and tree-dweller." As for arboreality, Chiappe et al. point out Confuciusornis' pedal phalangeal proportions are intermediate between arboreal and terrestrial birds, and that its hallux is shorter than most perching birds. I'll admit they seem to lean too far towards the terrestrial interpretation. And if Feduccia's correct that the illustration has a mesopubic pelvis and incorrectly attached remiges, I'll give him points there too (Chiappe et al., 1999 properly orient the pubis and do not comment on the remigial attachment). Of course, a criticism of the cover illustration of a popular science magazine from seven years ago might be better placed in the letters section of that magazine seven years ago. As it was. By Feduccia et al..


Topic 6- Endothermy of dinosaurs and basal birds.

Feduccia confuses endothermy with metabolic rate, and offers a hopelessly simplified conclusion- "... metabolic rates
in dinosaurs and early birds may have differed little from those in many extant reptiles (Ruben et al., 2003)." Paul (2002) and Padian and Horner (2004) provide good summaries of why the issue is more complex, and dinosaur physiology was in many ways more similar to birds than other living reptiles.
He spends some time arguing enantiornithines were varied in how altricial and precocial they were, to counter Zhou and Zhang's (2004) statement basal precociality for birds is congruent with precocial maniraptorans. His evidence is that Liaoxiornis is supposedly altricial (why?) and that perching taxa are basically never precocial. I recall there was a thread about precociality/altriciality on the list not long ago, though I didn't pay attention. I've never studied the topic, and it really doesn't matter, as living birds vary in their precociality and we all think maniraptorans are bird relatives anyway.



Topic 7- Feduccia flounders with definitions.

"As noted earlier, the question of whether birds are derived from dinosaurs depends on what one defines as dinosaur, or the Dinosauromorpha (Feduccia, 1999a, p. 91). We know little about the origin of dinosaurs, and we know little about the interrelationships."
We actually know a hell of a lot about both those things. And while there are a few different definitions of Dinosauria out there, all are equivalent when it comes to what is and is not a dinosaur.


"To illustrate the difficulty of defining the various dinosaur groups, Carroll (1988, p. 290) pointed out that ?The ?carnosaur? families may each have evolved separately from different groups that have been classified as coelurosaurs.?"
LOL Why? Why do you make it so easy to insult you, Feduccia? I know that _I_ go to Carroll (1988) whenever I need my dinosaur phylogeny questions answered. ;) Ughh. And he mentions Gauthier (1986), Currie and Padian (1997) and The Dinosauria 2nd. Ed. in the next paragraph. Feduccia also has issues with phylogenetic taxonomy, and I agree with him definitions of Saurischia, Theropoda and Coelurosauria utilizing birds are inappropriate.


Apparently, there's a tendancy for us dinosaur workers "to gloss over major problems of phylogenetics in the field. For example, in the new, 861-page 2nd edition of The Dinosauria (Weishampel et al., 2004), the chapter on dinosaur origins (Benton, 2004, p. 16) devotes only two paragraphs to the monophyly of Dinosauria! (Larsson, 2005)." Okay, Feduccia, you may not realize this, but dinosaurian monophyly hasn't been a problem since the early eighties. There's nothing to gloss over. Workers sorted it out over a decade ago (Gauthier, 1986; Brinkman and Sues, 1987; Novas, 1992; Sereno and Novas, 1993; Sereno, 1993; Novas, 1996)


Topic 8- Feduccia tackles maniraptorans.

"The problem also seems further complicated by the fact that a number of bird-like theropods occur some 80 million years after the appearance of Archaeopteryx."
That's Late Maastrichtian to Early Danian for those counting. Come on. Even Deinonychus is only 25 million years younger than Archaeopteryx. Blah blah... temporal paradox... no reference to Brochu and Norell (2001). Maybe someone should send Feduccia a copy of the Ostrom Symposium volume.


Feduccia argues for neoflightless maniraptorans, which I have no problem with. Doesn't affect bird origins though, and just because you call all ornithurines (in the sense of taxa closer to Aves than Archaeopteryx) birds doesn't mean they weren't theropods too. He brings up support from Czerkas' terrible book (http://dml.cmnh.org/2002Sep/msg00774.html) and Paul's (2002) infinitely superior one, but manages to keep quiet about the fact the latter places Maniraptora inside Theropoda.

"Microraptors, unlike true theropods, also lacked a supra-acetabular shelf (Martin, 2004) for efficient bipedal locomotion, and had many avian features (Czerkas et al., 2002; Paul, 2002; Martin, 2004) (Figs. 27, 28), such as an avian hand and distal pubic spoon (hypopubic cup), as opposed to the dinosaurian pubic boot, to mention only a few."
I suppose Tyrannosaurus isn't a true theropod, as it lacks a supracetacular crest too. See my critique of Martin (2004) for more details. Microraptor, like every other theropod and bird, lacks a hypopubic cup (Hwang et al., 2004).


"[Epidendrosaurus] was described as an arboreal coelurosaur, but there are no definitive synapomorphies that link this creature to
any specific group of theropods (and there is no satisfactory definition of coelurosaur), and Czerkas and Yuan (2002) considered it to be a pre-theropod, or basal archosaur."
You would think that with his dislike of phylogenetic nomenclature, Feduccia wouldn't be so anal about the definition of Coelurosauria. He knows damn well what dinosaur workers mean when they use the term, as it's encompassed the same taxa since 1990 (with the addition of tyrannosaurs and therizinosaurs in the mid-90's).


"Like the term ?thecodont,? a collective term to describe Triassic basal archosaurs, coelurosaur and carnosaur describe, respectively, small and large theropod dinosaurs."
No they don't, you ignorant man. Please stop brandishing about your pre-90's dinosaur phylogenetic knowledge as if it were relevent.


"As Paul (2002, p. 179) correctly notes, ?Euparkeria [Trias. S. Africa] is a suitable ancestral type for birds ? and ? Euparkeria
is a good ancestral type for all archosaurs.?
Hey, look! Feduccia takes another note from the creationists- quote mining. What does Paul REALLY say?
"Few dispute that Euparkeria is a suitable ancestral type for birds. But it is suitable only in the same sense that an early Cenozoic, primitive, generalized primate is a suitable ancestral type for humans. In addition, there is no evidence of flight-related adaptations. Euparkeria is important to bird origins only in that it represents the earliest Mesozoic and most primitive archosaur stem stock from which the entire dinosaur-bird clade later evolved. For that matter, Euparkeria is a suitable ancestral type for virtually all dinosaurs."
Amazing the difference 70 or so words make. And Feduccia didn't even quote the tiny part he excerpted correctly.


"Czerkas and Yuan (2002) argued that Scansoriopteryx showed that avian status was derived prior to the advent of theropods, and it certainly lacks characteristic theropod synapomorphies, even including the absence of a pre-acetabular shelf, but it has a reversed hallux."
Certainly lacks them. Why, just look at the synapomorphies of Theropoda according to Rauhut (2003)-
1. Fifth digit of the manus absent, and fourth digit reduced to the metacarpal and only one phalanx.
2. Presence of deep extensor pits on the dorsal surface of the distal end of the metacarpals.
3. Penultimate phalanx of the second digit of the manus longer than first phalanx.
Why, Scansoriopteryx merely has three of those three characters.
But of course, Rauhut includes Eoraptor and herrerasaurids as theropods. What about his synapomorphies for neotheropods?
1. More than three sacral vertebrae.
2. Presence of an enlarged distal carpal that overlaps the proximal ends of metacarpals I and II.
3. Shaft of Mc III considerably more slender than shaft of Mc II.
4. Third finger of the hand shorter than second finger.
5. Dolichoiliacic ilium.
6. Presence of a notch between the obturator process of the ischium and the ischial shaft distally.
7. Metatarsal I reduced, attached to Mt II and does not reach the ankle joint proximally.
Scansoriopteryx does lack characters 3, 4 and 6, but all coelurosaurs lack 6.
I suppose those seven theropod synapomorphies it has don't exist.


"Microraptors lack many of the typical theropod synapomorphies, including the pre-acetabular shelf characteristic of obligate bipeds, and have numerous avian features, including the diagnostic pubic spoon, partially reversed hallux, etc."
It's deja vu. And no, there's no evidence for reversed halluces in microraptorians.



Finally, the conclusion is a critique of cladistics.


I have mixed reactions regarding this paper. Feduccia's sections were painful in their inaccuracy and constant use of extremely outdated ideas. In addition, many of his refutations seemed to not incorporate his placement of maniraptorans as birds. He argues too hard for things that don't change dinosaurian birds, like neoflightless maniraptorans. And the reasons maniraptorans couldn't be theropods are never addressed. Also not addressed are several relevent critiques to points he's used for years now. Most angering is his utter twisting of Paul's words in the Euparkeria quote, to completely reverse the intent of Paul's statement. _Especially_ after he states in press releases that BADists are helping the creationist cause.
On the other hand, I thought Lingham-Soliar's collagen work was pretty decent. He could be on to something for a few specimens, and the Psittacosaurus is very important. I also enjoyed how both the basal coelurosaur feather issue and the homeotic frameshift issue had only tentative conclusions. I agree both need more work. These latter points made this the best BAND paper I've read.


Mickey Mortimer