|
Eocene–Oligocene Extinction Event
The Eocene–Oligocene extinction event, also called the Eocene-Oligocene transition or ''Grande Coupure'', is the transition between the end of the Eocene and the beginning of the Oligocene, an extinction event and faunal turnover occurring between 33.9 and 33.4 million years ago marked by large-scale extinction and floral and faunal turnover (although minor in comparison to the largest mass extinctions). Most of the affected organisms were marine or aquatic in nature. They included the last of the ancient ungulates, the " condylarths". This was a time of major climatic change, especially cooling, not clearly caused by any single major impact or volcanic event. Extended volcanic activity is one possible cause. Another speculation points to several large meteorite impacts near this time, including those of the Chesapeake Bay crater and the Popigai impact structure of central Siberia, which scattered debris perhaps as far as Europe. New dating of the Popigai meteor strengthens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest continent, being about 40% larger than Europe, and has an area of . Most of Antarctica is covered by the Antarctic ice sheet, with an average thickness of . Antarctica is, on average, the coldest, driest, and windiest of the continents, and it has the highest average elevation. It is mainly a polar desert, with annual precipitation of over along the coast and far less inland. About 70% of the world's freshwater reserves are frozen in Antarctica, which, if melted, would raise global sea levels by almost . Antarctica holds the record for the lowest measured temperature on Earth, . The coastal regions can reach temperatures over in summer. Native species of animals include mites, nematodes, penguins, seals and tardigrades. Where ve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choeropotamidae
Choeropotamidae, also known as Haplobunodontidae, are a family of extinct mammals, extinct herbivores, belonging to artiodactyls. They lived between the lower/middle Eocene and lower Oligocene (about 48 - 30 million years ago) and their remains were found in Europe and Africa. Description Choeropotamidae had the classic archaic appearance of primitive artiodactyls, with an unspecialized body and relatively small size. However, since the middle Eocene, choeropotamids began to develop some characteristics that will be found, more accentuated, in the suiforms: bunodonti molars (low and wide crown) and short legs. Partially complete fossils with shapes such as '' Amphirhagatherium'' indicate that these animals still had a relatively elongated tail, slender legs shorter than those of other archaic artiodactyls, an elongated and flexible body, and a long snout. The length of these animals would not exceed 1 meter, and the weight was around 5 to 10 kilograms. Classification Choeropo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xiphodontidae
Xiphodontidae is an extinct family of even-toed ungulates (order Artiodactyla), endemic to Europe during the Eocene 40.4—33.9 million years ago, existing for about 7.5 million years. They were, most likely, all terrestrial herbivores. ''Paraxiphodon'' suggests that they survived into the Lower Oligocene, at least. Taxonomy The Xiphodontidae were named by Flower (1883). It was assigned to Artiodactyla by Cope (1889); to Xiphodontoidea by Hooker (1986); and to Tylopoda Tylopoda (meaning "calloused foot") is a suborder of terrestrial herbivorous even-toed ungulates belonging to the order Artiodactyla. They are found in the wild in their native ranges of South America and Asia, while Australian feral camels ... by Carroll (1988).R. L. Carroll. 1988. Vertebrate Paleontology and Evolution. W. H. Freeman and Company, New York 1-698 References {{Taxonbar, from=Q2699941 Tylopoda Eocene even-toed ungulates Prehistoric mammals of Europe Prehistoric mammal famil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anoplotheriidae
Anoplotheriidae is an extinct family of even-toed ungulates ( order Artiodactyla). They were endemic to Western Europe during the Eocene and Oligocene epochs about 48—23 million years ago (Mya), existing for about 25 million years. They disappeared at the end of the Oligocene, leaving no survivors today. Its name is derived from the grc, ἂνοπλος ("unarmed") and θήριον ("beast"), translating as "unarmed beast". They were most likely mid-sized terrestrial herbivores not too distantly related to camels, but smaller and low-slung with long and thick tails, and rather generalistic. The climate during their time was warmer than today, and their habitats were probably subtropical or even tropical, with plentiful rainfall and abundant vegetation. Tropical rainforest may at least initially have occurred all over the Anoplotheriidae's range. Ecologically, they may have resembled a large duiker of our time (e.g. the similarly sized yellow-backed duiker ''Cephalophus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horse
The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature, '' Eohippus'', into the large, single-toed animal of today. Humans began domesticating horses around 4000 BCE, and their domestication is believed to have been widespread by 3000 BCE. Horses in the subspecies ''caballus'' are domesticated, although some domesticated populations live in the wild as feral horses. These feral populations are not true wild horses, as this term is used to describe horses that have never been domesticated. There is an extensive, specialized vocabulary used to describe equine-related concepts, covering everything from anatomy to life stages, size, colors, markings, breeds, locomotion, and behavior. Horses are adapted to run, allowing them to quickly escape predators, and po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeotheriidae
Palaeotheriidae is an extinct family of herbivorous perissodactyl mammals related to equids. They ranged across Europe and Asia from the Eocene through to the early Oligocene 55–33 Ma, existing for approximately . Living in dense forests, they ate soft leaves, shoots, berries, and leaf matter picked up from the forest floor. Morphology Palaeothere sizes ranged from at the shoulder, and weighed an estimated .S. Legendre. 1988. Les communautes de mammiferes du Paleogene (Eocene superieur et Oligocene) d'Europe occidentale: structure, milieux et evolution. Ph.D. thesis, Universite des Sciences et Techniques du Languedoc, Montpellier, France. 2 volumes. 1-265 Extinction Evidence suggests that the palaeotheriidae went extinct in Eurasia during the Early Oligocene, approximately 33 Ma, as part of a faunal turnover event known as the Grande Coupure. The Eocene-Oligocene transition marked a significant global cooling event caused by the onset of Antarctic glaciation. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can be also be referred to as an ''endemism'' or in scientific literature as an ''endemite''. For example '' Cytisus aeolicus'' is an endemite of the Italian flora. '' Adzharia renschi'' was once believed to be an endemite of the Caucasus, but it was later discovered to be a non-indigenous species from South America belonging to a different genus. The extreme opposite of an endemic species is one with a cosmopolitan distribution, having a global or widespread range. A rare alternative term for a species that is endemic is "precinctive", which applies t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hans Georg Stehlin
Hans Georg Stehlin (1870–1941) was a Swiss paleontologist and geologist. Stehlin specialized in vertebrate paleontology, particularly the study of Cenozoic mammals. He published numerous scientific papers on primates and ungulates. He was president of the commission of the Natural History Museum of Basel. In 1910 Stehlin coined the term '' Grande Coupure'' to refer to the extinction event which occurred 33.9 millions of years ago, which defines the Eocene- Oligocene limit. It originated a huge change in organisms, especially the mammals of Europe. (in French). Stehlin is commemorated in the scientific name of a species of lizard, ''Gallotia stehlini''.Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. Baltimore: Johns Hopkins University Press. xiii + 296 pp. ("Stehlin", p. 252). References Bibliography * External links *Stehlin, H.G. (1903). "''Die Säugetiere des schweizerischen Eocaens: critischer Catalog der Materialien'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Switzerland
). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel, St. Gallen a.o.). , coordinates = , largest_city = Zürich , official_languages = , englishmotto = "One for all, all for one" , religion_year = 2020 , religion_ref = , religion = , demonym = , german: Schweizer/Schweizerin, french: Suisse/Suissesse, it, svizzero/svizzera or , rm, Svizzer/Svizra , government_type = Federal assembly-independent directorial republic with elements of a direct democracy , leader_title1 = Federal Council , leader_name1 = , leader_title2 = , leader_name2 = Walter Thurnherr , legislature = Federal Assembly , upper_house = Council of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relict (biology)
In biogeography and paleontology, a relict is a population or taxon of organisms that was more widespread or more diverse in the past. A relictual population is a population currently inhabiting a restricted area whose range was far wider during a previous geologic epoch. Similarly, a relictual taxon is a taxon (e.g. species or other lineage) which is the sole surviving representative of a formerly diverse group. Definition A relict (or relic) plant or animal is a taxon that persists as a remnant of what was once a diverse and widespread population. Relictualism occurs when a widespread habitat or range changes and a small area becomes cut off from the whole. A subset of the population is then confined to the available hospitable area, and survives there while the broader population either shrinks or evolves divergently. This phenomenon differs from endemism in that the range of the population was not always restricted to the local region. In other words, the species or grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Endemic")