Platypterygius sp. (fossil ichthyosaur) (Cretaceous; Weston County, Wyoming, USA) 2 : 無料・フリー素材/写真
Platypterygius sp. (fossil ichthyosaur) (Cretaceous; Weston County, Wyoming, USA) 2 / 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 | Platypterygius sp. - fossil ichthyosaur skull from the Cretaceous of Wyoming, USA. (public display, Sternberg Museum of Natural History, Hays, Kansas, USA)Ichthyosaurs are an extinct group of large, predatory, marine reptiles. They had a fusiform body similar in gross morphology to modern dolphins and porpoises. The latter are mammals, while ichthyosaurs were reptiles. The evolution of similar body plans in unrelated organisms is called convergent evolution. Ichthyosaurs and dolphins are the most commonly cited examples of this evolutionary process.Ichthyosaur fossils are only found in Mesozoic sedimentary rocks - they first appear in the Triassic and go extinct in the Cretaceous.-------------From museum signage:Ichthyosaurs, or "fish-reptiles", were highly specialized marine reptiles. Their deep, streamlined bodies and large crescent-shaped tail fins made them fast, efficient swimmers. They hunted over wide areas, pursuing and catching their prey.The thick cone shape of this ichthyosaur's teeth suggests that it fed on large, fleshy prey that put up a fight.-------------Classification: Animalia, Chordata, Vertebrata, Reptilia, Ichthyosauria, OphthalmosauridaeStratigraphy: unrecorded/undisclosed Cretaceous unitLocality: unrecorded/undisclosed site in Weston County, northeastern Wyoming, USA-------------See info. at:en.wikipedia.org/wiki/Platypterygiusanden.wikipedia.org/wiki/Ichthyosaur |
| 撮影日 | 2012-06-13 09:47:05 |
| 撮影者 | James St. John |
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