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Puijila
''Puijila darwini'' is an extinct species of stem-pinniped (seal) which lived during the Miocene about 21 to 24 million years ago. About a metre (3 feet) long, the animal had only minimal physical adaptations for swimming. Unlike modern pinnipeds, it did not have flippers and its shape was otter-like, albeit more specialized; its skull and teeth are the features that most clearly indicate that it is a seal. It is considered to be the most primitive pinnipedimorph yet found. The genus name is an Inuktitut word for a young seal; the species name honours Charles Darwin. The holotype and only known specimen is a nearly complete fossil skeleton. It is housed at the Canadian Museum of Nature, Ottawa, Ontario. Background ''Puijila darwini'' was a semi-aquatic carnivore which represents a morphological link in early pinniped evolution. Its fossil shows enlarged, probably webbed feet, robust forelimbs and an unspecialized tail. This suggests that ''Puijila'' swam quadrupedally using i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinniped
Pinnipeds (pronounced ), commonly known as seals, are a widely range (biology), distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammals. They comprise the extant taxon, extant families Odobenidae (whose only living member is the walrus), Otariidae (the eared seals: sea lions and fur seals), and Phocidae (the earless seals, or true seals), with 34 extant species and more than 50 extinct species described from fossils. While seals were historically thought to have descended from two ancestral lines, molecular phylogenetics, molecular evidence supports them as a monophyletic group (descended from one ancestor). Pinnipeds belong to the suborder Caniformia of the order Carnivora; their closest living relatives are musteloids (Mustelidae, weasels, Procyonidae, raccoons, skunks and red pandas), having diverged about 50 million years ago. Seals range in size from the and Baikal seal to the and southern elephant seal. Several species exhibit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devon Island
Devon Island (, ) is an island in Canada and the largest desert island, uninhabited island (no permanent residents) in the world. It is located in Baffin Bay, Qikiqtaaluk Region, Nunavut, Canada. It is one of the largest members of the Arctic Archipelago, the second-largest of the Queen Elizabeth Islands, Canada's List of Canadian islands by area, sixth-largest island, and the List of islands by area, 27th-largest island in the world. It has an area of (slightly smaller than Croatia). The bedrock is Precambrian gneiss and Paleozoic siltstones and shales. The highest point is the Devon Ice Cap at which is part of the Arctic Cordillera. Devon Island contains several small mountain ranges, such as the Treuter Mountains, Haddington Range and the Cunningham Mountains. The notable similarity of its surface to that of Mars has attracted interest from scientists. History and settlement Robert Bylot and William Baffin were the first Europeans to sight Devon Island in 1616. William Parr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natalia Rybczynski
Natalia Rybczynski is a Canadian paleobiologist, professor and researcher. She is a research scientist with the Canadian Museum of Nature and holds a professorship at Carleton University in Ottawa, Ontario. Her doctorate was obtained at Duke University and her main interests are evolutionary functional morphology, particularly at the polar climes. Rybczynski is notable for having discovered a previously unknown carnivorous arctic mammal, a proto-seal, which represents a "missing link" between land-dwelling mammals and modern day ocean-going seals. '' Puijila darwini'' was discovered in 2007 on Devon Island in the Canadian arctic. Discovery of this specimen was announced in the journal ''Nature'' in April 2009. She has also contributed to the understanding of the biomechanics of ''Suminia'', a primitive mammal thought to exhibit early evidence of teeth and jaw structure specialized for chewing. Her discovery of a fossil tibia of a High Arctic camel was featured in a November 20 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enaliarctos
''Enaliarctos''From Greek language, Greek , ''enalios'', of the sea; and , ''arktos'', bear, "referring to the arctoid, including ursid, Carnivora" (Mitchell & Tedford, 1973, p. 218). is an extinct genus of Pinnipedimorpha, pinnipedimorph, and may represent the ancestor to all pinnipeds. The five species in the genus ''Enaliarctos'' have been recovered from late Oligocene and early Miocene (ca. 28-17 million years ago) strata of California and Oregon. Description It had a short tail and developed limbs with webbed feet. Unlike modern sea lions, it had a set of slicing carnassials; the presence of slicing teeth (rather than purely piercing teeth as in modern fish-eating pinnipeds) suggests that ''Enaliarctos'' needed to return to shore with prey items in order to masticate and ingest them. Still, ''Enaliarctos'' had some sea lion-like characteristics, such as large eyes, sensitive vibrissae, whiskers, and a specialized inner ear for hearing underwater. Evolution ''Enaliarctos'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene
The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from Ancient Greek (''olígos'') 'few' and (''kainós'') 'new', and refers to the sparsity of Neontology, extant forms of Mollusca, molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period. The Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major chang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaeopteryx
''Archaeopteryx'' (; ), sometimes referred to by its German name, "" ( ''Primeval Bird'') is a genus of bird-like dinosaurs. The name derives from the ancient Greek (''archaîos''), meaning "ancient", and (''ptéryx''), meaning "feather" or "wing". Between the late 19th century and the early 21st century, ''Archaeopteryx'' was generally accepted by palaeontologists and popular reference books as the oldest known bird (member of the group Avialae). Older potential avialans have since been identified, including ''Anchiornis'', ''Xiaotingia'', '' Aurornis'', and '' Baminornis''. ''Archaeopteryx'' lived in the Late Jurassic around 150 million years ago, in what is now southern Germany, during a time when Europe was an archipelago of islands in a shallow warm tropical sea, much closer to the equator than it is now. Similar in size to a Eurasian magpie, with the largest individuals possibly attaining the size of a raven, the largest species of ''Archaeopteryx'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird
Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a four-chambered heart, and a strong yet lightweight Bird skeleton, skeleton. Birds live worldwide and range in size from the bee hummingbird to the common ostrich. There are over 11,000 living species and they are split into 44 Order (biology), orders. More than half are passerine or "perching" birds. Birds have Bird wing, wings whose development varies according to species; the only known groups without wings are the extinct moa and elephant birds. Wings, which are modified forelimbs, gave birds the ability to fly, although further evolution has led to the Flightless bird, loss of flight in some birds, including ratites, penguins, and diverse endemism, endemic island species. The digestive and respiratory systems of birds are also uniquely a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2007 In Paleontology
Plants Angiosperms General paleobotanical research *An approximately Pennsylvanian ( Desmoinesian) age rainforest is reported from the Herrin #6 coal mine in Illinois by DiMichele ''et al''. Fungi newly named Arthropoda Crustaceans Research * Schram (2007) publishes a revision of Paleozoic The Paleozoic ( , , ; or Palaeozoic) Era is the first of three Era (geology), geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago (Ma), it succeeds the Neoproterozoic (the last era of the Proterozoic Eon) and ends 251.9 Ma a ... stomatopods, erecting the families Gorgonophontidae and Daidalidae. New taxa Insects New taxa Fish Bony fish * * * Cartilaginous fish * Archosauromorphs Pseudosuchians Pterosaurs Newly named non-dinosaurian dinosauromorphs Newly named non-avian dinosauromorphs Data courtesy of George Olshevky's dinosaur genera list. Newly named birds Lepidosauromorpha Plesiosaurs * * Synapsids Non-mammalian Mammals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nunavut
Nunavut is the largest and northernmost Provinces and territories of Canada#Territories, territory of Canada. It was separated officially from the Northwest Territories on April 1, 1999, via the ''Nunavut Act'' and the Nunavut Land Claims Agreement, ''Nunavut Land Claims Agreement Act'', which provided this territory to the Inuit for self-government. The boundaries had been drawn in 1993. The creation of Nunavut resulted in the territorial evolution of Canada, first major change to Canada's political map in half a century since the province of Newfoundland and Labrador, Newfoundland (now Newfoundland and Labrador) was admitted in 1949. Nunavut comprises a major portion of Northern Canada and most of the Arctic Archipelago. Its vast territory makes it the list of the largest country subdivisions by area, fifth-largest country subdivision in the world, as well as North America's second-largest (after Greenland). The capital Iqaluit (formerly "Frobisher Bay"), on Baffin Island in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canada
Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of countries and dependencies by area, second-largest country by total area, with the List of countries by length of coastline, world's longest coastline. Its Canada–United States border, border with the United States is the world's longest international land border. The country is characterized by a wide range of both Temperature in Canada, meteorologic and Geography of Canada, geological regions. With Population of Canada, a population of over 41million people, it has widely varying population densities, with the majority residing in List of the largest population centres in Canada, urban areas and large areas of the country being sparsely populated. Canada's capital is Ottawa and List of census metropolitan areas and agglomerations in Canada, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
