At the Museum 



American Museum S Natural History 



www.amnh.org 



Extremely Long- Necked Sauropod 

 Named by AMNH Paleontologists 



Artist's conception of the living £. ellisoni 



Two American Museum of Natural History paleon- 

 tologists have described a new species of sauropod, 

 Erketu ellisoni, that had an extremely elongated 

 neck, one of the longest necks proportional to trunk 

 height of all known sauropods. The truly impressive fea- 

 ture of this dinosaur was not its bulk or overall length, but 

 the length of its neck — especially in comparison to the 

 rest of its body. Most sauropods had long necks extending 

 from large bodies, but E. ellisoni took this to an extreme. A 

 single neck vertebra from E. ellisoni measures more than 

 half a yard (nearly two feet) long. Based on the partial neck 

 recovered from this specimen, the Museum team esti- 

 mates that the full neck was more than eight yards long. 



The new finding is described in the peer-reviewed journal 

 American Museum Novitates by Daniel T. Ksepka, a gradu- 

 ate student enrolled at Columbia University who studies at 

 the American Museum of Natural History, and Mark A. 

 Norell, Curator in the Museum's Division of Paleontology. 



The fossil, which also includes a chest plate, two lower 

 leg bones, and a potato-sized anklebone, was discovered 

 in 2002 during the exploration of a new site, Bor Guve, 



as part of the Museum's annual joint paleontological ex- 

 peditions to the great fossil beds of Mongolia's Gobi 

 Desert with the Mongolian Academy of Sciences. 



The neck vertebrae of E. ellisoni illustrate some of the in- 

 teresting evolutionary strategies sauropods used to re- 

 duce the burden of their long, cumbersome necks. The 

 sides of the bones feature large concavities where air sacs 

 would have existed. Computed tomography (CT) scans re- 

 veal that the vertebrae are not solid, but instead are filled 

 with numerous small pneumatic chambers that would 

 have reduced their weight. Also, spines along the top of 

 some of the vertebrae were split into two parallel tracks 

 rather than one, as with the human spine. The channel 

 between the two spine rails probably allowed room for a 

 ligament to help support the neck. 



The generic name for the new sauropod comes from 

 Erketu, one of 99 deities chronicled from pre-Buddhist 

 Mongolian shamanistic tradition; Erketu was the god of 

 might. The species name honors Mick Ellison, Senior 

 Principal Artist at the Museum, whose work has signifi- 

 cantly contributed to dinosaur research. 



