Helicoprion ferrieri (fossil shark tooth whorl) (Skinner Ranch Formation, Lower Permian; Dugout Mountain, Brewster County, Texas, USA) 3 : 無料・フリー素材/写真
Helicoprion ferrieri (fossil shark tooth whorl) (Skinner Ranch Formation, Lower Permian; Dugout Mountain, Brewster County, Texas, USA) 3 / James St. John
| ライセンス | クリエイティブ・コモンズ 表示 2.1 |
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| 説明 | Helicoprion ferrieri (Hay, 1907) - fossil shark tooth whorl from the Permian of Texas, USA. (public display, FMNH PF 7445, Field Museum of Natural History, Chicago, Illinois, USA)This remarkable fossil is a symphyseal tooth whorl from the lower jaw of an edestoid shark. It is in fossiliferous limestone of the Permian-aged Skinner Ranch Formation of Texas. Sharks have a cartilaginous skeleton and mineralized, phosphatic teeth (as are all vertebrate teeth). Helicoprion is undoubtedly the strangest shark in geologic history (see reconstructions elsewhere in this photo album). The specimen shown here is described in Kelly & Zangerl (1976) - Helicoprion (Edestidae) in the Permian of West Texas. Journal of Paleontology 50: 992-994.Some paleontologists have interpreted the tooth whorl of this shark as part of a coiled lower jaw that may have been whipped outward and back to capture fish prey. Although intriguing, this type of reconstruction is almost certainly incorrect. Instead of an external lower tooth whorl, the tooth whorl was likely internal. The latter interpretation is based on well-preserved specimens with soft-part preservation from concretions in the Permian-aged Phosphoria Formation of southeastern Idaho, USA.Classification: Animalia, Chordata, Vertebrata, Chondrichthyes, Elasmobranchii, Eugeneodontida, Edestoidea, Agassizodontidae/HelicoprionidaeStratigraphy: Decie Ranch Member, Skinner Ranch Formation, Wolfcampian Series lower Lower PermianLocality: Dugout Mountain, northern Brewster County, Glass Mountains, western Texas, USA-------------------------See info. at:web.uri.edu/celsnews/two-uri-biologists-solve-mystery-of-... |
| 撮影日 | 2010-08-21 17:02:09 |
| 撮影者 | James St. John |
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