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Anachronornis
''Anachronornis'' is a genus of extinct bird from the Late Paleocene (Thanetian) of North America. One species has been described, ''Anachronornis anhimops'', from the Willwood Formation in Wyoming. It is a basal anseriform, relative of modern waterfowl. Etymology ''Anachronornis'' is derived from Ancient Greek ἀναχρονισμός ("out of time") and ὄρνις ("bird"), referring to the unexpectedly late appearance of a species close to the divergence between the two major waterfowl lineages, Anhimae and Anseres. The species name ''anhimops'', from ''Anhima'' and ὄψῐς ("face", "appearance"), refers to the appearance of the head and bill to that of the screamer genus ''Anhima''. Description ''Anachronornis'' has been described as screamer-like in the literature, although it shared characteristics with both screamer-line and duck-line anseriforms, placing it close to the divergence between the two groups. It had a "fowl-like" bill (non-spatulate, the basal c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anseriformes
Anseriformes is an order (biology), order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which includes over 170 species of waterfowl, among them the ducks, goose, geese, and swans. Most modern species in the order are highly adapted for an aquatic existence at the water surface. With the exception of screamers, males have Penis#Birds, penises, a trait that has been lost in the Neoaves, the clade consisting of all other modern birds except the galliformes and paleognaths. Due to their aquatic nature, most species are web-footed. Evolution Anseriformes are one of only two types of modern bird to be confirmed present during the Mesozoic alongside the other dinosaurs, and in fact were among the very few birds to survive their extinction, along with their cousins, the Galliformes. These two groups only occupied two ecologic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anseriform
Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which includes over 170 species of waterfowl, among them the ducks, geese, and swans. Most modern species in the order are highly adapted for an aquatic existence at the water surface. With the exception of screamers, males have penises, a trait that has been lost in the Neoaves, the clade consisting of all other modern birds except the galliformes and paleognaths. Due to their aquatic nature, most species are web-footed. Evolution Anseriformes are one of only two types of modern bird to be confirmed present during the Mesozoic alongside the other dinosaurs, and in fact were among the very few birds to survive their extinction, along with their cousins, the Galliformes. These two groups only occupied two ecological niches during the Mesozoic, liv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Willwood Formation
The Willwood Formation is a sedimentary sequence deposited during the late Paleocene to early Eocene, or Clarkforkian, Wasatchian and Bridgerian in the NALMA classification.Willwood Formation at .orgNeasham & Vondra, 1972 Description It consists of fine grained clastic rocks ( and ) interbedded with medium grained clastic rocks ( |
Screamer
The screamers are three South American bird species placed in Family (biology), family Anhimidae. They were thought to be related to the Galliformes because of similar beak, bills, but are more closely related to the family Anatidae, i.e. ducks and allies, and the magpie goose, within the clade Anseriformes. The clade is exceptional within the living birds in lacking uncinate processes of ribs. The three species are: The horned screamer (''Anhima cornuta''); the southern screamer or crested screamer (''Chauna torquata''); and the northern screamer or black-necked screamer (''Chauna chavaria''). Systematics and evolution Anhimids are most similar to Presbyornithidae, presbyornithids, with which they may form a clade to the exclusion of the rest of Anseriformes. Given the presence of lamelae in the otherwise fowl-like beaks of screamers, it is even possible that they evolved from Presbyornithidae, presbyornithid-grade birds, reverting from a filter-feeding lifestyle to an herbivoro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anhimae
The screamers are three South American bird species placed in family Anhimidae. They were thought to be related to the Galliformes because of similar bills, but are more closely related to the family Anatidae, i.e. ducks and allies, and the magpie goose, within the clade Anseriformes. The clade is exceptional within the living birds in lacking uncinate processes of ribs. The three species are: The horned screamer (''Anhima cornuta''); the southern screamer or crested screamer (''Chauna torquata''); and the northern screamer or black-necked screamer (''Chauna chavaria''). Systematics and evolution Anhimids are most similar to presbyornithids, with which they may form a clade to the exclusion of the rest of Anseriformes. Given the presence of lamelae in the otherwise fowl-like beaks of screamers, it is even possible that they evolved from presbyornithid-grade birds, reverting from a filter-feeding lifestyle to an herbivorous one. Screamers have a poor fossil record. ''Anachrono ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterygoid Bone
The pterygoid is a paired bone forming part of the palate of many vertebrates, behind the palatine bone In anatomy, the palatine bones (; derived from the Latin ''palatum'') are two irregular bones of the facial skeleton in many animal species, located above the uvula in the throat. Together with the maxilla, they comprise the hard palate. Stru ...s. It is a flat and thin lamina, united to the medial side of the pterygoid process of the sphenoid bone, and to the perpendicular lamina of the palatine bone. References Bones of the head and neck {{musculoskeletal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleontology In Wyoming
Paleontology in Wyoming includes research into the prehistoric life of the U.S. state of Wyoming as well as investigations conducted by Wyomingite researchers and institutions into ancient life occurring elsewhere. The fossil record of the US state of Wyoming spans from the Precambrian to recent deposits. Many fossil sites are spread throughout the state. Wyoming is such a spectacular source of fossils that author Marian Murray noted in 1974 that " en today, it is the expected thing that any great museum will send its representatives to Wyoming as often as possible." Murray has also written that nearly every major vertebrate paleontologist in United States history has collected fossils in Wyoming. Wyoming is a major source of dinosaur fossils. Wyoming's dinosaur fossils are curated by museums located all over the planet. During the Precambrian, Wyoming was covered by a shallow sea inhabited by stromatolite-forming bacteria. This sea remained in place during the early Paleozoic e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleogene Birds Of North America
The Paleogene Period ( ; also spelled Palaeogene or Palæogene) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period Ma (million years ago) to the beginning of the Neogene Period Ma. It is the first period of the Cenozoic Era, the tenth period of the Phanerozoic and is divided into the Paleocene, Eocene, and Oligocene epochs. The earlier term Tertiary Period was used to define the time now covered by the Paleogene Period and subsequent Neogene Period; despite no longer being recognized as a formal stratigraphic term, "Tertiary" still sometimes remains in informal use. Paleogene is often abbreviated "Pg", although the United States Geological Survey uses the abbreviation "" for the Paleogene on the Survey's geologic maps. Much of the world's modern vertebrate diversity originated in a rapid surge of diversification in the early Paleogene, as survivors of the Cretaceous–Paleogene extinction event took advantage of empty ecologica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Taxa Described In 2023
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of ''Tiktaalik'' in the arctic of Canada. Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. Early edition, published online before print. The ob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thanetian
The Thanetian is, in the International Commission on Stratigraphy, ICS Geologic timescale, the latest age (geology), age or uppermost stage (stratigraphy), stratigraphic stage of the Paleocene epoch (geology), Epoch or series (stratigraphy), Series. It spans the time between . The Thanetian is preceded by the Selandian Age and followed by the Ypresian Age (part of the Eocene). The Thanetian is sometimes referred to as the Late Paleocene. Stratigraphic definition The Thanetian was established by Switzerland, Swiss geologist Eugène Renevier in 1873. The Thanetian is named after the Thanet Formation, the oldest Cenozoic deposit of the London Basin, which was first identified in the area of Kent (southern England) known as the Isle of Thanet. The base of the Thanetian Stage is laid at the base of magnetic chronozone C26n. The references profile (Global Boundary Stratotype Section and Point) is in the Zumaia section (43° 18'N, 2° 16'W) at the beach of Itzurun, Pais Vasco, northern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Park County, Wyoming
Park County is a County (United States), county in the U.S. state of Wyoming. As of the 2020 United States census, the population was 29,624. The county seat is Cody, Wyoming, Cody. Park County is a major tourism destination. The county has over 53 percent of Yellowstone National Park's land area. Many attractions abound, including the Buffalo Bill Historical Center, the Cody Stampede Rodeo, the Ghost Town of Kirwin, Wyoming, Kirwin, and the western museum Old Trail Town. History Wyoming gained separate territorial status in 1868. Before that, most of the state's area was included in either Laramie County, Wyoming, Laramie County (part of the Dakota Territory) or as unorganized territory within the Dakota Territory. Wyoming Territory was established on July 25, 1868, at which time Laramie County was assigned to this jurisdiction. The area now known as Park County was established as Carter County, then Sweetwater County. In 1884 it was assigned to Fremont County; this continued u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
