Sunday, November 16, 2014

Dawndraco: Prehistoric Animal of the Week

This week we will be checking out a new discovered species of pterosaur that was discovered way back in the 1970s.  Let's celebrate Dawndraco kanzai!

Dawndraco was a large pterosaur that sported a twenty foot wingspan and soared over the oceans that once covered what is now Kansas, USA, during the Late Cretaceous, 86 million years ago.  Back then a shallow body of salt water covered much of the mid-western United States, called the Western Interior Seaway.  During this time, Dawndraco coexisted with many marine creatures including sharks, like Scapanorhyncus, turtles, plesiosaurs, mosasaurs, like Tylosaurus, and its close relative, Geosternbergia.  Its genus and species name translates to "Dawn Dragon from Kansas".

Fossil remains of Dawndraco kanzai at the American Museum of Natural History in New York.

The discovery and naming of Dawndraco is an interesting story that really starts in 1974 when scientists discovered a beautifully preserved pterosaur skeleton they identified as a Pteranodon sternbergi.  At the time, the genus Pteranodon included two species; Pteranodon longiceps, which had the pointed crests and is the most common pterosaur image in popular culture, and Pteranodon sternbergi, which possessed a wide, triangular-shaped crest.  Fast forward to 2010 and paleontologists are revisiting the Pteranodon genus.  They decided that since Pteranodon longiceps and Pteranodon sternbergi really lived a few million years apart and had very different crests, that Pteranodon sternbergi should get its own genus and so it was renamed Geosternbergia sternbergi.  While they were conducting this research, they realized that the specimen found in the 70s was actually different from both Pteranodon and Geosternbergia.  Its beak was broader longitudinally and the base of its skull was more narrow.  They quickly realized that they had yet another new genus on their hands that had been lying in the museum for decades and never realized it, and thus Dawndraco was born.

Sketch showcasing the three pterosaurs formerly all belonging to the genus, Pteranodon by Christopher DiPiazza.

Dawndraco's wings were exceptionally long and narrow, perfect for soaring over long distances.  This idea is reinforced by the fact that where it was discovered was in the middle of a sea, miles away from any shores at the time that it was alive.  It may have behaved similarly to modern seabirds that also fly long distances over the ocean like Albatross.  Dandraco's beak was extremely long, and possessed no teeth.  Some scientists suggest it hunted prey like small fish and mollusks by plucking them from the ocean's surface as it flew overhead.  Others believe it was more suited to diving into the water and using its long bill and body like a missile to ambush fast-swimming prey.  Dawndraco's skull sadly only preserved the base of the crest so the exact shape of its head ornamentation is somewhat of a mystery.

Life reconstruction of Dawndraco kanzai by Christopher DiPiazza.

That is all for this week!  As always feel free to comment below or on our facebook page!

References

Kellner, A.W.A. (2010). "Comments on the Pteranodontidae (Pterosauria, Pterodactyloidea) with the description of two new species". Anais da Academia Brasileira de Ciências 82 (4): 1063–1084. doi:10.1590/S0001-37652010000400025.

Witton, Mark P. Pterosaurs: Natural History, Evolution, Anatomy. N.p.: n.p., n.d. Print.

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