hesperornis

hesperornis
/hes'peuh rawr"nis/, n.
a toothed aquatic bird of the extinct genus Hesperornis, fossils of which are found in rocks of Cretaceous age in Kansas, having the rear legs modified for swimming and reaching a length of more than 4 ft. (1.2 m).
[ < NL (1872) < Gk Hésper(os) HESPERUS + órnis bird]

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▪ fossil bird genus
 extinct birds found as fossils in Late Cretaceous Period deposits dating from about 120 million to 65 million years ago; this bird is known mostly from the Great Plains region of the United States, but some remains have been found as far north as Alaska. Hesperornis was primitive in that teeth were present in the lower jaw; the rear portion of the upper jaw also had teeth. This evidence suggests that the horny beak characteristic of today's birds had not yet evolved in Hesperornis.

      Hesperornis was clearly an actively swimming bird that probably chased and caught fish. Although unrelated to today's loons (loon) (order Gaviiformes), many of Hesperornis's skeletal features resembled those of loons, and, like loons, Hesperornis is thought to have been a good diver. The wings were small and useless for flight, and the wing bones were splintlike. The breastbone lacked the prominent keel that serves as an anchor for powering flight muscles. The legs, however, were powerfully developed and clearly adapted for rapid diving and swimming through water. The neck was slender and the head long and tapered; both were probably capable of rapid side-to-side movement.

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Universalium. 2010.

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Look at other dictionaries:

  • Hesperornis — Hesperornis …   Wikipédia en Français

  • hesperornis — HESPERÓRNIS s.m. Pasăre fosilă acvatică, asemănătoare cu pinguinul, cu aripile reduse la două palete, care a trăit în cretacic şi care face trecerea de la reptile la păsări. – Din fr. hesperornis. Trimis de gall, 13.09.2007. Sursa: DEX 98 … …   Dicționar Român

  • hesperornis — hesperòrnis m DEFINICIJA zool. geol. izumrli rod zubatih ptica bez krila (Hesperornis regalis), iz razdoblja krede u Sjevernoj Americi ETIMOLOGIJA nlat. Hesperornis ← grč. hésperos: večer, zapad + órnis: ptica …   Hrvatski jezični portal

  • Hesperornis — Hes pe*ror nis, n. [NL., fr. Gr. ? western + ?, ?, a bird.] (Paleon.) A genus of large, extinct, wingless birds from the Cretaceous deposits of Kansas, belonging to the Odontornithes. They had teeth, and were essentially carnivorous swimming… …   The Collaborative International Dictionary of English

  • Hesperŏrnis — Marsh., Vogelgattung aus der Unterordnung der Ratitae und der Gruppe der Odontolcae, H. regalis Marsh. (s. Tafel »Kreideformation II«, Fig. 11), ein 1,8 m langer, flügelloser Schwimmvogel mit kiellosem Brustbein, Zähnen im Ober und Unterkiefer,… …   Meyers Großes Konversations-Lexikon

  • Hesperórnis — Hesperórnis, fossiler Vogel, ein tauchender Fischfresser, aus der Kreide Nordamerikas, über 1 m hoch, flugunfähig …   Kleines Konversations-Lexikon

  • hesperornis — ● hesperornis nom masculin Oiseau fossile à dents, du crétacé d Amérique du Nord, probablement aptère et aquatique …   Encyclopédie Universelle

  • Hesperornis — Hargeria redirects here. This is also an (invalid) name of a genus of tanaidacean crustaceans in the family Leptocheliidae. Hesperornis Temporal range: Late Cretaceous, 83.5–78 Ma …   Wikipedia

  • Hesperornis — Hesperornis …   Wikipédia en Français

  • Hesperornis —   Hesperornis Escala temporal: Cretácico superior …   Wikipedia Español

  • Hesperornis — Hesperornithiformes Lebendrekonstruktion von Hesperornis regalis Zeitraum Kreidezeit 110 bis 65 Mio. Jahre Fossilfundorte Nordamerika: Kansas (Niobrara Kreide) …   Deutsch Wikipedia

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