Thursday, October 25, 2012

Dinosaur Feathers: First North American Find

Its no secret that certain dinosaurs had feathers at this point.  This is largely due to the abundant fossils from places like China and a few from Europe that clearly show evidence of plumage on beautifully preserved theropod skeletons.  In 2008, however, the first ever dinosaurs from North America were discovered with actual feathers.

Fossil feathers from one of the Ornithomimus specimens at the Royal Tyrrell Museum in Canada

 The dinosaur is not a newly discovered species, its called Ornithomimus and was a very close relative to Struthiomimus which has been talked about previously on this site.  Two adults and one juvenile were found, all three possessing evidence of plumage.  The younger animal has what appears to be fluffy down-type feathers like modern juvenile birds and the adults had quill knobs, like those found on Velociraptor skeletons, proving that it would have had large, wing-type feathers on its arms. Whats interesting is that veined, wing feathers are usually implications of flight, looking at modern birds.  Ornithomimus clearly wasn't much of a flyer, however.  It would have been too large and heavy.  This discovery suggests that perhaps these feathers were originally evolved for something like sexual display or brooding (also observable in modern birds) and later were adapted for flight in certain kinds of animals (not Ornithomimids).



It has been assumed for a while now that Ornithomimids (family of dinosaurs Ornithomimus belongs to) had feathers.  Its only logical to think this way since every other type of dinosaur surrounding them on the theropod family tree (Tyrannosauroids, Oviraptorids, Dromaeosaurids, Therizinosaurids, Compsognathids, birds...) has at least one specimen on the fossil record that clearly shows feathers in some form or another.  Ornithomimids were the only ones that didn't...until now.  The icing on the cake is that its in North America too!  On that note I also should mention this discovery also kills any misconceptions that some people may have had thinking only feathered dinosaurs came from places like China.  In reality feathered dinosaurs were all over the world, many of them already discovered in the form of skeletons and bones where the feathers didn't preserve like Deinonychus, for instance.  Fossilization is rare to begin with let alone preservation of soft tissue! 

Struthiomimus I painted earlier this year with incorrect featherless arms.

Luckily I was able to correct it!


Works Cited

 Hartman, Scott. "Skeletal Drawing: Ornithomimus Had Wings...as an Adult." Skeletal Drawing: Ornithomimus Had Wings...as an Adult. N.p., n.d. Web. 25 Oct. 2012. <http://skeletaldrawing.blogspot.ca/2012/10/ornithomimus-had-wingsas-adult.html>.

"Dinosaurs May Have Evolved Feathers for Courtship." NewScientist- Life. N.p., n.d. Web. 25 Oct. 2012. <http://www.newscientist.com/article/dn22428-dinosaurs-may-have-evolved-feathers-for-courtship.html>.

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