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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 various species of the family Corvidae. 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 nonmammalian species able to recognize itself in a mirror test. Magpies have shown the ability to make and use tools, imitate human speech, grieve, play games, and work in teams. 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 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 Au ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Early Paleocene
The Danian is the oldest age (geology), age or lowest stage (stratigraphy), stage of the Paleocene Epoch or series (stratigraphy), Series, of the Paleogene Period or system (stratigraphy), System, and of the Cenozoic Era or Erathem. The beginning of the Danian (and the end of the preceding Maastrichtian) is at the Cretaceous–Paleogene extinction event . The age ended , being followed by the Selandian. Stratigraphic definitions The Danian was introduced in scientific literature by Germany, German-Switzerland, Swiss geologist Pierre Jean Édouard Desor in 1847 following a study of fossils found in France and Denmark.Danien Den Store Danske Encyklopædi He identified this stage in deposits from Faxe and Møns Klint and named it after the Latin name for Denmark. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the more recent 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, Aus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hornerstown Formation
The Hornerstown Formation is a latest Cretaceous to early Paleocene-aged geologic Formation (geology), formation in New Jersey. It preserves a variety of fossil remains, including those of dinosaurs, and contains direct evidence of the Mass mortality event, mass mortality that occurred at the Cretaceous–Paleogene boundary, Cretaceous-Paleogene boundary.Weishampel, et al. (2004). "Dinosaur distribution." Pp. 517-607. Outcrops of the Hornerstown Formation are known from sites such as Edelman Fossil Park. Age & significance The age of the Hornerstown deposits have been controversial. While most fossils are of animal taxa known from the earliest Cenozoic era, several fossils of otherwise exclusively Cretaceous age have been found. These include remains of the shark ''Squalicorax'', several types of non-avian dinosaurs, the teleost fish ''Enchodus'', several species of ammonite, and marine lizards referred to the genus ''Mosasaurus''. Some of these remains show signs of severe ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anatalavis
''Anatalavis'' is genus of prehistoric birds related to ducks and geese, perhaps to the magpie-goose (''Anseranas semipalmata'') in particular. Alternatively, it might have been a more basal lineage of Anserimorphae distinct from the living waterfowl, similar or even related to the roughly contemporary '' Conflicto antarcticus'' from the Danian of Antarctica.Tambussi ''et al.'' 2019 Species The type species ''Anatalavis rex'' is known from Hornerstown, New Jersey, and its remains were collected by J.G.Meirs in 1869 and W.Ross in 1878. They are probably from the Hornerstown Formation (Late Cretaceous or Early Paleocene, some 66 million years ago) – usually, they are assumed to be from the lower Maastrichtian layer of the Hornerstown Formation, but they might be younger and postdate the Mesozoic, or even from the slightly older Navesink Formation, as these deposits are reworked and locally mixed across the K-Pg boundary, and no exact locality data was recorded fo ... [...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''. 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 prin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vegavis Iaai
''Vegavis'' is a genus of extinct bird that lived in Antarctica during the Maastrichtian stage of the Late Cretaceous. The type and only species is ''Vegavis iaai'', representing one of the earliest known crown group birds. Initially described as member of Anseriformes within Galloanserae, the definitive taxonomic position of ''Vegavis'' was debated among paleontologists over two decades until the 2025 description of a nearly complete skull, discovered in 2011, supported its original classification. Taxonomy The genus name, ''Vegavis'', is a combination of the name of Vega Island and "avis", the Latin word for bird, while the species name, "iaai", is after the acronym for Instituto Antartico Argentino (IAA), the Argentine scientific expedition to Antarctica. The holotype is held by the Museo de La Plata, Argentina. The specimen, cataloged as MLP 93-I-3-1, was found in 1993 from the López de Bertodano Formation at Cape Lamb on Vega Island, Antarctica, and was first thought ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous–Paleogene Extinction Event
The Cretaceous–Paleogene (K–Pg) extinction event, also known as the K–T extinction, was the extinction event, mass extinction of three-quarters of the plant and animal species on Earth approximately 66 million years ago. The event caused the extinction of all non-avian dinosaurs. Most other tetrapods weighing more than also became extinct, with the exception of some ectothermic species such as sea turtles and crocodilians. It marked the end of the Cretaceous period, and with it the Mesozoic era, while heralding the beginning of the current era, the Cenozoic. In the geologic record, the K–Pg event is marked by a thin layer of sediment called the Cretaceous–Paleogene boundary, K–Pg boundary or K–T 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 le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Living Fossil
A living fossil is a Deprecation, deprecated term for an extant taxon that phenotypically 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 punctuated equilibrium, 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 Morphology (biology), morphological changes. Scientific investigations have repeatedly discredited such claims. The minimal superficial changes to living foss ... [...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. Theoretical implications Monotypic taxa present several important theoretical challenges in biological classification. One key issue is known as "Gregg's Paradox": if a single species is the only member of multiple hierarchical levels (for example, being the only species in its genus, which is the only genus in its family), then each level needs a distinct definition to maintain logical structure. Otherwise, the different taxonomic ranks become effectively identical, which creates problems for organizing biological diversity in a hierarchical syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swan
Swans are birds of the genus ''Cygnus'' within the family Anatidae. The swans' closest relatives include the goose, geese and ducks. Swans are grouped with the closely related geese in the subfamily Anserinae where they form the tribe (biology), tribe Cygnini. Sometimes, they are considered a distinct subfamily, Cygninae. They are the largest Anseriformes, waterfowl and are often among the largest Bird flight, flighted birds in their range. 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 separation sometimes occurs, particularly following nesting failure, and if a mate dies, the remaining swan will take up with another. The number of bird egg, eggs in each :wikt:clutch, clutch ranges from three to eight. Taxonomy and terminology The genus ''Cygnus'' was introduced in 1764 by the French naturalist François Alexandre Pier ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
