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Magpie Goose
The magpie goose (''Anseranas semipalmata'') is the sole living representative species of the family Anseranatidae. This common waterbird is found in northern Australia and southern New Guinea. As the species is prone to wandering, especially when not breeding, it is sometimes recorded outside its core range. The species was once also widespread in southern Australia but disappeared from there largely due to the drainage of the wetlands where the birds once bred. Due to their importance to Aboriginal people as a seasonal food source, as subjects of recreational hunting, and as a tourist attraction, their expansive and stable presence in northern Australia has been "ensured yprotective management". Description Magpie geese are unmistakable birds with their black and white plumage and yellowish legs. The feet are only partially webbed, and the magpie goose feeds on vegetable matter in the water, as well as on land. Males are larger than females. Unlike true geese, their molt i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magpie
Magpies are birds of the Corvidae family. Like other members of their family, they are widely considered to be intelligent creatures. The Eurasian magpie, for instance, is thought to rank among the world's most intelligent creatures, and is one of the few non-mammal species able to recognize itself in a mirror test. They are particularly well known for their songs and were once popular as cagebirds. In addition to other members of the genus '' Pica'', corvids considered as magpies are in the genera '' Cissa'', '' Urocissa'', and '' Cyanopica''. Magpies of the genus ''Pica'' are generally found in temperate regions of Europe, Asia, and western North America, with populations also present in Tibet and high-elevation areas of Kashmir. Magpies of the genus ''Cyanopica'' are found in East Asia and the Iberian Peninsula. The birds called magpies in Australia are, however, not related to the magpies in the rest of the world. Name References dating back to Old English call the bird ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Screamer
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 ducks (family Anatidae),Todd, F. (1991) and most closely related to the magpie goose. 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 Screamers have a poor fossil record. A putative Eocene specimen is known from Wyoming, while the more modern ''Chaunoides antiquus'' is known from the late Oligocene to early Miocene in Brazil. Anhimids are most similar to presbyornithids, with which they 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 e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hornerstown Formation
The Hornerstown Formation is a Paleogene or latest Mesozoic geologic formation in New Jersey.Weishampel, et al. (2004). "Dinosaur distribution." Pp. 517-607. The age of these deposits have been controversial. While most fossils are of animals types known from the earliest Cenozoic era, several fossils of otherwise exclusively Cretaceous age have been found. These include remains of the shark ''Squalicorax'', the teleost fish '' Enchodus'', several species of ammonite, and marine lizards referred to the genus '' Mosasaurus''. Some of these remains show signs of severe abrasion and erosion, however, implying that they are probably re-worked from older deposits. Most of these fossils are restricted to the lowest point in the formation, one rich in fossils and known as the Main Fossiliferous Layer, or MFL. Other explanations for the out-of-place fossils in the MFL is that they represent a time-averaged assemblage that built up and remained unburied during a time of low sediment deposit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatalavis
''Anatalavis'' is genus of prehistoric birds related to ducks and geese, perhaps in particular the magpie-goose. The species ''Anatalavis rex'' – formerly placed in ''Telmatornis'' – is known from the Hornerstown Formation (Late Cretaceous or Early Paleocene, some 66 million years ago) of New Jersey. ''Anatalavis oxfordi'' was described based on fossils found in the Eocene (Ypresian age) London Clay (about 55 mya) at Walton-on-the-Naze, England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b .... References * Dyke, GJ (2000) "The fossil waterfowl (Aves: Anseriformes) from the Tertiary of England," ''J. Vertebr. Paleontol.'' 20: 39A. Dyke, GJ (2001) "The fossil waterfowl (Aves: Anseriformes) from the Eocene of England," ''American Museum Novitates'' No. 3354, 15 pp. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil
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''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the abs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vegavis Iaai
''Vegavis'' is a genus of extinct bird that lived during the Late Cretaceous (Maastrichtian stage) of Antarctica, some 68 to 66 mya. Among modern birds, most studies show that ''Vegavis'' is most closely related to ducks and geese (Anatidae), but it is not considered to be a direct ancestor of them, although other studies question these results. Taxonomy The holotype specimen of ''Vegavis'' is held by the Museo de La Plata, Argentina. The specimen, cataloged as MLP 93-I-3-1, was found in the López de Bertodano Formation at Cape Lamb on Vega Island, Antarctica, in 1993, but was only described as a new species in 2005 because it consists of the very delicate remains of one bird embedded in a concretion, which had to be meticulously prepared for study. CT scans were utilized to gain a clearer picture of the bone structure without running danger of damaging or destroying the fossil. The genus name, ''Vegavis'', is a combination of the name of Vega Island and "avis", the Lat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous–Paleogene Extinction Event
The Cretaceous–Paleogene (K–Pg) extinction event (also known as the Cretaceous–Tertiary extinction) was a sudden extinction event, mass extinction of three-quarters of the plant and animal species on Earth, approximately 66 million years ago. With the exception of some ectothermic species such as sea turtles and crocodilians, no tetrapods weighing more than survived. It marked the end of the Cretaceous Period, and with it the Mesozoic era, while heralding the beginning of the Cenozoic era, which continues to this day. In the geologic record, the K–Pg event is marked by a thin layer of sediment called the Cretaceous–Paleogene boundary, K–Pg boundary, which can be found throughout the world in marine and terrestrial rocks. The boundary clay shows unusually high levels of the metal iridium, which is more common in asteroids than in the Earth's crust. As originally proposed in 1980 by a team of scientists led by Luis Walter Alvarez, Luis Alvarez and his son Walter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Living Fossil
A living fossil is an extant taxon that cosmetically resembles related species known only from the fossil record. To be considered a living fossil, the fossil species must be old relative to the time of origin of the extant clade. Living fossils commonly are of species-poor lineages, but they need not be. While the body plan of a living fossil remains superficially similar, it is never the same species as the remote relatives it resembles, because genetic drift would inevitably change its chromosomal structure. Living fossils exhibit stasis (also called "bradytely") over geologically long time scales. Popular literature may wrongly claim that a "living fossil" has undergone no significant evolution since fossil times, with practically no molecular evolution or morphological changes. Scientific investigations have repeatedly discredited such claims. The minimal superficial changes to living fossils are mistakenly declared as an absence of evolution, but they are examples of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magpie Goose Taking Off
Magpies are birds of the Corvidae family. Like other members of their family, they are widely considered to be intelligent creatures. The Eurasian magpie, for instance, is thought to rank among the world's most intelligent creatures, and is one of the few non-mammal species able to recognize itself in a mirror test. They are particularly well known for their songs and were once popular as cagebirds. In addition to other members of the genus '' Pica'', corvids considered as magpies are in the genera '' Cissa'', ''Urocissa'', and ''Cyanopica''. Magpies of the genus ''Pica'' are generally found in temperate regions of Europe, Asia, and western North America, with populations also present in Tibet and high-elevation areas of Kashmir. Magpies of the genus ''Cyanopica'' are found in East Asia and the Iberian Peninsula. The birds called magpies in Australia are, however, not related to the magpies in the rest of the world. Name References dating back to Old English call the bird a "p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotypic
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispecific" or "monospecific" is sometimes preferred. In botanical nomenclature, a monotypic genus is a genus in the special case where a genus and a single species are simultaneously described. In contrast, an oligotypic taxon contains more than one but only a very few subordinate taxa. Examples Just as the term ''monotypic'' is used to describe a taxon including only one subdivision, the contained taxon can also be referred to as monotypic within the higher-level taxon, e.g. a genus monotypic within a family. Some examples of monotypic groups are: Plants * In the order Amborellales, there is only one family, Amborellaceae and there is only one genus, '' Amborella'', and in this genus there is only one species, namely ''Amborella trichopoda.' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swan
Swans are birds of the family Anatidae within the genus ''Cygnus''. The swans' closest relatives include the geese and ducks. Swans are grouped with the closely related geese in the subfamily Anserinae where they form the tribe Cygnini. Sometimes, they are considered a distinct subfamily, Cygninae. There are six living and many extinct species of swan; in addition, there is a species known as the coscoroba swan which is no longer considered one of the true swans. Swans usually mate for life, although "divorce" sometimes occurs, particularly following nesting failure, and if a mate dies, the remaining swan will take up with another. The number of eggs in each clutch ranges from three to eight. Etymology and terminology The English word ''swan'', akin to the German , Dutch and Swedish , is derived from Indo-European root ' ('to sound, to sing'). Young swans are known as '' cygnets'' or as '' swanlings''; the former derives via Old French or (diminutive suffix et 'little') from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
