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Hesperornithiform
Hesperornithes is an extinct and highly specialized group of aquatic avialans closely related to the ancestors of modern birds. They inhabited both marine and freshwater habitats in the Northern Hemisphere, and include genera such as ''Hesperornis'', ''Parahesperornis'', ''Baptornis'', ''Enaliornis'', and ''Potamornis'', all strong-swimming, predatory divers. Many of the species most specialized for swimming were completely flightless. The largest known hesperornithean, ''Canadaga arctica'', may have reached a maximum adult length of . Hesperornitheans were the only Mesozoic avialans to colonize the oceans. They were wiped out in the Cretaceous–Paleogene extinction event, along with enantiornitheans and all other non-avian dinosaurs, and many other diverse plant and animal groups. Anatomy and ecology Most of what is known about this group rests on analyses of single species, as few provide sufficiently complete fossils for analysis. Although some of the smaller and more basal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hesperornis BW (white Background)
''Hesperornis'' (meaning "western bird") is a genus of cormorant-like bird that spanned the first half of the Campanian age of the Late Cretaceous period (83.5–78 mya). One of the lesser-known discoveries of the paleontologist O. C. Marsh in the late 19th century Bone Wars, it was an early find in the history of avian paleontology. Locations for ''Hesperornis'' fossils include the Late Cretaceous marine limestones from Kansas and the marine shales from Canada. Nine species are recognised, eight of which have been recovered from rocks in North America and one from Russia. Description ''Hesperornis'' was a large bird, reaching up to in length. It had virtually no wings, and swam with its powerful hind legs. Studies on the feet initially indicated that ''Hesperornis'' and kin had lobed toes similar to modern-day grebes, as opposed to webbed toes as seen in most aquatic birds such as loons. More recent work looking at the morphometrics of the feet in hesperornithiformes and mod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hesperornis Regalis
''Hesperornis'' (meaning "western bird") is a genus of cormorant-like bird that spanned the first half of the Campanian age of the Late Cretaceous period (83.5–78 mya). One of the lesser-known discoveries of the paleontologist O. C. Marsh in the late 19th century Bone Wars, it was an early find in the history of avian paleontology. Locations for ''Hesperornis'' fossils include the Late Cretaceous marine limestones from Kansas and the marine shales from Canada. Nine species are recognised, eight of which have been recovered from rocks in North America and one from Russia. Description ''Hesperornis'' was a large bird, reaching up to in length. It had virtually no wings, and swam with its powerful hind legs. Studies on the feet initially indicated that ''Hesperornis'' and kin had lobed toes similar to modern-day grebes, as opposed to webbed toes as seen in most aquatic birds such as loons. More recent work looking at the morphometrics of the feet in hesperornithiformes and mod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hesperornis
''Hesperornis'' (meaning "western bird") is a genus of cormorant-like bird that spanned the first half of the Campanian age of the Late Cretaceous period (83.5–78 mya). One of the lesser-known discoveries of the paleontologist O. C. Marsh in the late 19th century Bone Wars, it was an early find in the history of avian paleontology. Locations for ''Hesperornis'' fossils include the Late Cretaceous marine limestones from Kansas and the marine shales from Canada. Nine species are recognised, eight of which have been recovered from rocks in North America and one from Russia. Description ''Hesperornis'' was a large bird, reaching up to in length. It had virtually no wings, and swam with its powerful hind legs. Studies on the feet initially indicated that ''Hesperornis'' and kin had lobed toes similar to modern-day grebes, as opposed to webbed toes as seen in most aquatic birds such as loons. More recent work looking at the morphometrics of the feet in hesperornithiformes and mod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canadaga
''Canadaga'' (meaning "Canadian bird") is a flightless bird genus from the Late Cretaceous. The single known species is ''Canadaga arctica''. It lived in the shallow seas around what today is Bylot Island in Nunavut, Canada. Its fossils were found in rocks dated to the mid-Maastrichtian age, about 67 million years ago. It was a member of the Hesperornithes, flightless toothed seabirds of the Cretaceous. Among these, it belonged to the Hesperornithidae, along with ''Hesperornis'', the well-known namesake genus. ''C. arctica'' is one of the largest known members of the Hesperornithes, reaching a length of . It also represents one of the last known members of the lineage.Holtz, Thomas R. Jr. (2008) ''Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages'Winter 2010 Supplementary Information Unlike its relatives which are mainly known from subtropical or tropical waters, this species seems to have ranged in temperate or even subarctic areas. The sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canadaga Arctica
''Canadaga'' (meaning "Canadian bird") is a flightless bird genus from the Late Cretaceous. The single known species is ''Canadaga arctica''. It lived in the shallow seas around what today is Bylot Island in Nunavut, Canada. Its fossils were found in rocks dated to the mid-Maastrichtian age, about 67 million years ago. It was a member of the Hesperornithes, flightless toothed seabirds of the Cretaceous. Among these, it belonged to the Hesperornithidae, along with ''Hesperornis'', the well-known namesake genus. ''C. arctica'' is one of the largest known members of the Hesperornithes, reaching a length of . It also represents one of the last known members of the lineage.Holtz, Thomas R. Jr. (2008) ''Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages'Winter 2010 Supplementary Information Unlike its relatives which are mainly known from subtropical or tropical waters, this species seems to have ranged in temperate or even subarctic areas. The sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brodavis
''Brodavis'' is a genus of freshwater hesperornithiform birds known from the Late Cretaceous (possibly Campanian and Maastrichtian stage) of North America and Asia. It was first described and named by Larry D. Martin, Evgeny N. Kurochkin and Tim T. Tokaryk in 2012 and assigned to a new monogeneric family, Brodavidae. Four species were described and assigned to ''Brodavis''. The type species, ''B. americanus'', is known from the holotype left metatarsal, RSM P 2315.1 which was collected in the Maastrichtian-age Frenchman Formation of Canada. ''B. baileyi'' is known from the holotype left metatarsal, UNSM 50665, which was collected in the Maastrichtian-age Hell Creek Formation of South Dakota, United States (dated to between 66.8 and 66 Ma agoLongrich, N.R., Tokaryk, T. and Field, D.J. (2011). "Mass extinction of birds at the Cretaceous–Paleogene (K–Pg) boundary." ''Proceedings of the National Academy of Sciences'', 108(37): 15253-15257. ) ''B. mongoliensis'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baptornis
''Baptornis'' ("diving bird") is a genus of flightless, aquatic birds from the Late Cretaceous, some 87-80 million years ago (roughly mid-Coniacian to mid-Campanian faunal stages). The fossils of ''Baptornis advenus'', the type species, were discovered in Kansas, which at its time was mostly covered by the Western Interior Seaway, a shallow shelf sea. It is now known to have also occurred in today's Sweden, where the Turgai Strait joined the ancient North Sea; possibly, it occurred in the entire Holarctic. Othniel Charles Marsh discovered the first fossils of this bird in the 1870s. This was, alongside the ''Archaeopteryx'', one of the first Mesozoic birds to become known to science. Ecology More material evidence exists for the ecology of ''B. advenus'' than for any other member of the Hesperornithes, with the possible exception of ''Hesperornis regalis'', but still much is left to conjecture. The loon-sized bird was of middle size among its relatives and had a markedly elonga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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