Another Flap Over Dinosaur Feathers

first_img(Visited 46 times, 1 visits today)FacebookTwitterPinterestSave分享0 The first North American “feathered dinosaur” has put the media in a frenzy of celebration over questionable data.Three Canadians from Alberta took a look at old fossils of the “ostrich-mimic” dinosaur Ornithomimus stored in drawers at the Royal Tyrrell Museum of Palaeontology, and found fibrous impressions in the sandstone they interpret as feathers on the forewings.  News media immediately launched an artwork-laden campaign of touting this as the first “feathered dinosaur” found outside of China and Germany (Archaeopteryx being the German claim).As soon as the paper hit Science, as if on cue, Science Daily, PhysOrg, Live Science, the BBC News and the other usual suspects put up Julius Csotonyi’s creative artwork from their paper in their coverage with no critique or alternative analysis whatsoever.  Strangely, the popular reports added colorful backgrounds of sky and forest that were not present in the small image in the paper, though the University of Calgary press release came fully illustrated.  Moreover, the popular reports simply parroted the interpretation of the feathers as courtship displays, while soft-pedaling the problems.And there are problems.  First of all, the rock impressions of the “feathers” consist mostly of straight lines that look nothing like the pennaceous flight feathers of Archaeopteryx.  One will read Zelenitsky’s paper in vain for mention the words vane, pennaceous or barbule in the main paper or supplemental information, except (for barbule) in the following curious circumlocution, “Evidence of shafted feathers {i.e., feathers with a rigid shaft, with or without interlocking barbules [type 3 feathers or higher (11, 12)]} is preserved on the forelimb bones of an adult Ornithomimus skeleton.”  The authors call them “filamentous feathers” with filamentous meaning just that: a filament or shaft, much simpler than the complex vanes of true feathers with their barbs, barbules and interlocking hooks.So do the photos of the fossils show these to be true feathers?  No; even the interpretive sketches show nothing but straight lines, with the exception of a very few tiny fragments shaped like a U or curve that, with copious imagination, might be interpreted as hooks for something, though they are disconnected from any barbs or barbules, which are not evident anywhere.  Further, these “feathers” are not connected to the skeleton, being separated by a centimeter or more at various angles from parallel to almost perpendicular.  They look like scratches in the rock.  Since the fossils were buried in sandstone instead of the limestone of German and Chinese fossils, license has to be taken to assume that such delicate impressions could be made in sandstone in this singular instance.  The authors tempted other researchers to go on a search for feathers in sandstone.Other problems present themselves with the “feathered dinosaur” interpretation.  All the others were theropods in the group of saurischian (lizard-hipped) dinosaurs.  This one is completely outside that group.  It’s in the ornithischian (bird-hipped) branch.  While that might sound like a plus for dinosaur-to-bird evolution theories, it would require evolutionists to postulate the emergence of the feather-whatever-things in the common ancestor long before flight supposedly evolved.  These feathers had nothing to do with the evolution of  flight.  The creatures were far too heavy for that.  The authors admit this by postulating that the “filamentous feathers” (found only on the adult) were used for courtship display.There was only one adult that showed the scratch marks, and one juvenile without them.  A third had markings on the bone.  Notice how their handling of the specimens adds to the confusion:Preparation of specimens with feathersTwo ornithomimosaur skeletons associated with fossilized feathers, TMP 2008.70.1 and TMP 2009.110.1, were preserved in hard, cemented sandstone blocks and prepared in 2008-2009. Preparation of this matrix could only be achieved with a Chicago Pneumatic (CP-9361) airscribe. In order to expose the feathers preserved in TMP 2008.70.1, the rock had to break along the parting plane on which the structures are preserved. In many instances, the rock did not break along that plane, resulting in the partial destruction of some filaments. In TMP 2009.110.1, the parting plane fortunately occurred between the sandstone and the ferruginous coating, revealing the presence of filamentous feathers in the ironstone.A third skeleton (TMP 1995.110.1) was preserved in a siltstone to fine-grained sandstone and displays markings on the left radius and ulna, inferred to be traces left by shafted feathers.  Although the markings were first discovered on the bones during specimen preparation in 1995, feathers impressions were not found in the matrix at the time.  (Supplemental Information, p. 2).The photo of 1995.110.1 shows only dark criss-cross markings on the bone that they “inferred to be traces left by shafted feathers.”  They don’t bear any resemblance to actual feathers.  This means that only one fossil had the carbonized impressions extending from parts of its forelimbs at some distance from the bones, leaving plenty of leeway to speculate about what they were, or whether they had any connection to the animal.  Yet their artwork shows the adult with fully-fledged wing feathers, barbs, barbules and all, and even multiple colors!Even the language they use to describe the “feathers” is couched with escape hatches.  “Their distribution and orientation are similar to the insertion pattern of covert feathers (20, 21), which form the bulk of the feather covering in modern bird wings,” they said.  “The shapes of the individual markings are consistent with the morphology of the rigid shafts of such feathers.”  The authors continually described their fossils as “primitive” as opposed to to “modern” birds.There’s no way this specimen can have anything to do with the origin of avian flight.  The authors did not even try to connect it to flight.  Feathers on this bulky dinosaur don’t help the arboreal or cursorial hypothesis.  It’s a stretch to connect it to courtship, either; the authors didn’t say if it was a male or female.  Any dinosaur so outfitted with feathers as the artwork suggests would seem to be seriously hampered from eating between courtship displays.  The authors used the power of suggestion to state, “Several roles have been proposed for primitive wings [gliding (23, 24), predatory behaviors (25, 26), or terrestrial locomotion (27, 28)], but their occurrence in a clade of ground-dwelling herbivorous (29) non-maniraptorans [the group that used to lump theropods with birds] suggests that they did not originate for predatory behaviors or aerial locomotion.” Reference 27 points to Ken Dial’s “wing assisted incline running” speculation he dreamed up by watching chukar partridge chicks (5/01/2006, 12/22/2003).  Since chukars are 100% birds, this amounts to a kind of recapitulation theory.Despite these problems, Science Now promoted the Zelenitsky paper with this overblown concoction of dogma, suggestion and composite explanation:Dinosaurs still walk—and fly—among us: We call them birds. Most paleontologists think birds descended from a group of winged dinosaurs, and thus dinos never went completely extinct. But where did the wings come from? New discoveries from Canada suggest that both wings and feathers arose earlier in dinosaur evolution than previously thought, possibly to attract members of the opposite sex or to protect hatching baby dinos.The headline was, “Dinosaurs Sprouted Wings Earlier Than Previously Thought,” even though the original paper only referred to the presence of a “pennibrachium,” defined as “a forelimb bearing long feathers that form a planar, wing-like surface but are not necessarily used in aerial locomotion.”   This definition is theory-laden since it was defined in reference to “feathered dinosaurs” (Royal Society).  Zelenitsky et al. referred to it as a “wing-like structure” but it’s basically a wrist adaptation that allows the arms of a dinosaur to fold, whether or not it was feathered.  Humans can fold their arms, too.Whatever the markings mean, therefore, they complicate the story of dinosaur-to-bird evolution.  One final observation: the specimens are found in upper Cretaceous, meaning that true birds were already flying around when it lived.  And an encore: the adult specimen exhibits the “dinosaur death pose” that indicates suffocation in water (2/16/2012, 11/23/2011).Original paper: Zelenitsky et al., “Feathered Non-Avian Dinosaurs from North America Provide Insight into Wing Origins,” Science 26 October 2012: Vol. 338 no. 6106 pp. 510-514, DOI: 10.1126/science.1225376.This shameful display of suggestive reporting in a leading scientific journal, promoted uncritically by the media, reveals the sad state of science these days.Ornithomimus was so named because of its resemblance to an ostrich.  Ostriches have feathery wings used for display and balance.  If this “dinosaur” had some kind of “filamentous feathers” (granting extremely generous license to speculation), so be it.  But evolutionists are going to need a lot better evidence than this.  More likely, the emotional mad dash to establish connections between dinosaurs and birds gives some researchers a Gold Rush mentality to strive for fame and fortune by stretching the truth.  Journal editors and science reporters are only to happy to oblige them, since another “feathered dinosaur” makes for good headlines, particularly when accompanied by wickedly overdrawn artwork (suggestion, extrapolation, visualization).Experienced readers will withhold acceptance of such wild claims, knowing full well a re-interpretation is likely, if not a retraction, after less Darwin-inebriated scientists take a look at the specimens.  Critics like Alan Feduccia and the Oregon State squad will doubtless have something to say (AIG).last_img

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