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Dromaeosaurs : ウィキペディア英語版 | Dromaeosauridae
Dromaeosauridae is a family of feathered theropod dinosaurs. They were small- to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek ''dromeus'' (''δρομευς'') meaning 'runner' and ''sauros'' (''σαυρος'') meaning 'lizard'. In informal usage they are often called raptors (after ''Velociraptor''), a term popularized by the film ''Jurassic Park''; a few types include the term "raptor" directly in their name and have come to emphasize their supposed bird-like habits. Dromaeosaurid fossils have been found across the globe in North America, Europe, Africa, Japan, China, Mongolia, Manchuria, Madagascar, Argentina, and Antarctica,〔Case, J.A., Martin, J.E., and Reguero, M. (2007). "A dromaeosaur from the Maastrichtian of James Ross Island and the Late Cretaceous Antarctic dinosaur fauna." Pp. 1–4 in Cooper, A., Raymond, C., and Team, I.E. (eds.), ''Antarctica: a Keystone in a Changing World – Online Proceedings for the Tenth International Symposium on Antarctic Earth Sciences'', U.S. Geological Survey Open-File Report 2007-1047, SRP 083. U.S. Geological Survey, Washington, D.C.〕 with fossilized teeth giving credence to the possibility that they inhabited Australia as well.〔http://dml.cmnh.org/1997Nov/msg00475.html〕 They first appeared in the mid-Jurassic Period (late Bathonian stage, about 167 million years ago) and survived until the end of the Cretaceous (Maastrichtian stage, 66 ma), existing for over 100 million years, up until the Cretaceous–Paleogene extinction event. The presence of dromaeosaurids as early as the Middle Jurassic has been confirmed by the discovery of isolated fossil teeth, though no dromaeosaurid body fossils have been found from this period. ==Description==
The distinctive dromaeosaurid body plan helped to rekindle theories that at least some dinosaurs may have been active, fast, and closely related to birds. Robert Bakker's illustration for John Ostrom's 1969 monograph,〔 showing the dromaeosaurid ''Deinonychus'' in a fast run, is among the most influential paleontological reconstructions in history.〔Paul, Gregory S. (2006) "Drawing Dinosaurs"(2006). "Geotimes", January 2006. http://www.geotimes.org/jan06/feature_drawingdinos.html〕 The dromaeosaurid body plan includes a relatively large skull, serrated teeth, narrow snout, and forward-facing eyes which indicate some degree of binocular vision. Dromaeosaurids, like most other theropods, had a moderately long S-curved neck, and their trunk was relatively short and deep. Like other maniraptorans, they had long arms that could be folded against the body in some species, and relatively large hands with three long fingers (the middle finger being the longest and the first finger being the shortest) ending in large claws. The dromaeosaurid hip structure featured a characteristically large pubic boot projecting beneath the base of the tail. Dromaeosaurid feet bore a large, recurved claw on the second toe. Their tails were slender, with long, low, vertebrae lacking transverse process and neural spines after the 14th caudal vertebra.〔 It is now known that at least some, and probably all, dromaeosaurids were covered in feathers, including large, vaned, wing and tail feathers. This development, first hypothesized in the mid-late 1980s and confirmed by fossil discoveries in 1999, represents a significant change in the way dromaeosaurids have historically been depicted in art and film.〔
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