Canadian Feathered Dinosaurs

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Canadian feathered dinosaurs found, according to BBC News and ScienceDaily25 October 2012, Fossil Science 28 October 2012 and Science, 2012; 338 (6106): 510 DOI: 10.1126/science.1225376. A team of palaeontologists led by Darla Zelenitsky from the University of Calgary and François Therrien from the Royal Tyrrell Museum of Palaeontology have studied three specimens of Ornithomimus edmontonicus found in Upper Cretaceous rocks in Alberta, Canada. The name Ornithomimus is derived from Latin for “bird mimic”. They had long hind legs, short forelimbs, a toothless beak, large eyes and a long, thick tail. In the film Jurassic Park they were portrayed as scaly creatures that ran on two legs like an ostrich.

The Canadian specimens are two adults and one juvenile, and the research team claim they were covered in short downy feathers, and one of the adults showed evidence of a pennibrachium - a structure with the form of a wing consisting of large long feathers. According to Darla Zelenitsky, “This is a really exciting discovery as it represents the first feathered dinosaur specimens found in the Western Hemisphere. Furthermore, despite the many ornithomimid skeletons known, these specimens are also the first to reveal ornithomimids were covered in feathers, like several other groups of theropod dinosaurs”.

The dinosaurs are too large to fly so the research team suggest the wing-like structures were used as courtship displays or for protecting young. Zelenitsky explained: “The presence of the primitive wings in these relatively large dinosaurs indicate that wings did not initially evolve for flight, and the occurrence of these wing-like structures in only the adult individual suggest that these structures were used later in life, perhaps for purposes like display or courtship”.

These findings fit with the belief (summarised by ScienceNOW) that dinosaurs “still walk and fly among us: we call them birds”. The researchers suggest their findings show dinosaurs evolved feathers earlier than previously thought. Darla Zelenitsky told the BBC World Service programme Science in Action: “The specimens from China that show wings, are dinosaurs that are more closely related to birds”. She went on to comment: “This particular dinosaur is a bit more distantly related to birds – it’s a more primitive dinosaur... it indicates wings evolved earlier than previously thought”.

BBC, Fossil Science, ScienceDaily

Editorial Comment: We noticed that media reports of this story were not accompanied by any detailed photos of the “feathers”. Instead they featured pics of the whole adult fossil, or an artist’s reconstruction showing an adult dinosaur covered in downy fuzz with elaborate fan shaped feathered structures on its arms hovering over a juvenile also covered with downy fuzz. All their readers would have been just as unimpressed as we were when we looked at the photos published in the Science article. The juvenile fossil and one of the adult fossils have some fine filamentous material surrounding their bones. The other adult, the one featured in the news reports, has some carbonised lines on one of its forearm bones, but no filaments on its body. There is nothing on any of the fossils that looks like a bird’s feather. This editor has seen not just the pictures, but one of the original fossils and is equally unimpressed.

In 2009 bird fossil expert Alan Feduccia University of North Carolina, Chapel Hill, published a report on “feathered dinosaurs” and stated that the filamentous material that is promoted as “proto-feathers” on dinosaur fossils is just collagen fibres from decaying skin. He commented: “Collagen is a scleroprotein, the chief structural protein of the connective tissue layer of skin. Naturally, because of its low solubility in water and its organization as tough, inelastic fiber networks, we would expect it to be preserved occasionally from flayed skin during the fossilization process”. (See our report Dinosaur Feathers or Fibres? and read Feduccia’s article here.)

These new fossils fit Feduccia’s description very well, and we repeat our previous comment about dinosaur filaments: if it wasn’t for the current obsession to link dinosaurs and birds no-one who'd ever seen a bird would ever claim these are feathers. We also note that one of the adult fossils (the one pictured in media reports) has its head thrown backwards in what is technically described as the “opisthotonic death pose” seen in many fossils. Last year scientists carried out experiments with dead chickens and concluded that the posture resulted from sudden immersion of land dwelling creatures in cold fresh water. Such dinosaurs were not fossilised by slow and gradual deposition. They were suddenly and catastrophically drowned, then buried rapidly and deeply to preserve such odd death poses. See our report  Dino Death Pose Recreated. (Ref. fossilisation, skin, proteins)

Evidence News 7 November 2012

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