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Hypogeomys
''Hypogeomys'' is a genus of rodents in the family Nesomyidae, found in Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa .... There is one extant species, the Malagasy giant rat (''Hypogeomys antimena''), currently an endangered species with a restricted range. There is also another species known from subfossils from a few thousand years ago, '' Hypogeomys australis''. ''H. antinema'' measures , making it the largest rodent in Madagascar, while ''H. australis'' seems to have been slightly larger.Goodman, S.M. and Rakotondravony, D. 1996The Holocene distribution of ''Hypogeomys'' (Rodentia: Muridae: Nesomyinae) on Madagascar. Biogéographie de Madagascar 1996:283–293. References Taxa named by Alfred Grandidier Rodent genera Mammal genera with one living sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypogeomys Australis
''Hypogeomys australis'' is an extinct rodent from central and southeastern Madagascar. First described in 1903, it is larger than its close relative, the living '' Hypogeomys antimena'', which occurs further west, but otherwise similar. Average length of the femur (upper leg bone) is 72.1 mm, compared to 63.8 mm in ''H. antimena''. One of the few extinct rodents of Madagascar, it survived to at least around 1536 BP based on radiocarbon dating. Little is known of its ecology, but it may have lived in burrows like its living relative and eaten some arid-adapted plants. Taxonomy ''Hypogeomys australis'' was described in 1903 by Guillaume Grandidier from subfossil material collected in the cave of Andrahomana in southeastern Madagascar. The ''Hypogeomys'' material was similar to the living '' Hypogeomys antimena'', but distinct enough for Grandidier to recognize it as a separate species, different in size and some morphological details. Grandidier described anot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malagasy Giant Rat
The Malagasy giant rat (''Hypogeomys antimena''), also known as the votsotsa or votsovotsa, is a nesomyid rodent found only in the Menabe region of Madagascar. It is an endangered species due to habitat loss, slow reproduction, and limited range (200 square kilometres north of Morondava, between the rivers Tomitsy and Tsiribihina) Pairs are monogamous and females bear only one or two young per year. It is the only extant species in the genus ''Hypogeomys''; another species, '' Hypogeomys australis'', is known from subfossil remains a few thousand years old. Physical description Malagasy giant rats have an appearance somewhat similar to rabbits, though maintaining many rat-like features especially in the face. Males and females both grow to roughly rabbit-size, around and , though with an additional of dark tail. They have a coarse coat which varies from gray to brown to reddish, darkening around the head and fading to white on the belly. They also have prominent, pointed e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypogeomys
''Hypogeomys'' is a genus of rodents in the family Nesomyidae, found in Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa .... There is one extant species, the Malagasy giant rat (''Hypogeomys antimena''), currently an endangered species with a restricted range. There is also another species known from subfossils from a few thousand years ago, '' Hypogeomys australis''. ''H. antinema'' measures , making it the largest rodent in Madagascar, while ''H. australis'' seems to have been slightly larger.Goodman, S.M. and Rakotondravony, D. 1996The Holocene distribution of ''Hypogeomys'' (Rodentia: Muridae: Nesomyinae) on Madagascar. Biogéographie de Madagascar 1996:283–293. References Taxa named by Alfred Grandidier Rodent genera Mammal genera with one living sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nesomyidae
The Nesomyidae are a family of African rodents in the large and complex superfamily Muroidea. It includes several subfamilies, all of which are native to either continental Africa or to Madagascar. Included in this family are Malagasy rodents, climbing mice, African rock mice, swamp mice, pouched rats, and the white-tailed rat. Characteristics Nesomyids are small- to medium-sized rodents, with the largest being the size of a rat. Physically, they may resemble mice, rats, voles, or hamsters, depending on the species and subfamily. Their diets vary from fairly strict herbivory to nearly pure insectivory. Their habits are similarly variable, with some species climbing trees, and others burrowing in the ground. They give birth to up to four young after a gestation period around six weeks. Classification Many of these animals were once thought to be related to other groups of muroid rodents, but this African-based clade has been proposed and confirmed on the basis of genetic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Pleistocene
The Early Pleistocene is an unofficial sub-epoch in the international geologic timescale in chronostratigraphy, being the earliest division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently estimated to span the time between 2.580 ± 0.005 Ma (million years ago) and 0.773 ± 0.005 Ma. The term Early Pleistocene applies to both the Gelasian Age (to 1.800 ± 0.005 Ma) and the Calabrian Age. While the Gelasian and the Calabrian have officially been defined by the International Union of Geological Sciences (IUGS) to effectively constitute the Early Pleistocene, the succeeding Chibanian and Tarantian ages have yet to be ratified. These proposed ages are unofficially termed the Middle Pleistocene and Late Pleistocene The Late Pleistocene is an unofficial Age (geology), age in the international geologic timescale in chronostratigraphy, also known as Upper Pleistocene from a Stratigraphy, stratigraphic perspective. It is intended to be the fourth div ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alfred Grandidier
Alfred Grandidier (20 December 1836 – 13 September 1921) was a French naturalist and explorer. From a very wealthy family, at the age of 20, he and his brother, Ernest Grandidier (1833–1912), undertook a voyage around the world. At first they were led by the astronomer and physicist Pierre Jules César Janssen (1824–1907), but when Janssen fell sick and had to return to France after about six months, the brothers continued the journey. They visited South America in 1858 and 1859 and in particular the Andes, Peru, Chile, Bolivia, Argentina and Brazil. During this voyage they gathered a significant collection of specimens which were analyzed, in 1860, by Ernest. The two brothers parted ways after this. Ernest Grandidier went to China and collected a vast number of specimens which are now in the Louvre and the Guimet museum. Alfred travelled to India, reaching it in 1863. He had intended to explore the high plateau of Tibet, but was prevented by a severe attack of fever. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodent
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are native to all major land masses except for New Zealand, Antarctica, and several oceanic islands, though they have subsequently been introduced to most of these land masses by human activity. Rodents are extremely diverse in their ecology and lifestyles and can be found in almost every terrestrial habitat, including human-made environments. Species can be arboreal, fossorial (burrowing), saltatorial/richochetal (leaping on their hind legs), or semiaquatic. However, all rodents share several morphological features, including having only a single upper and lower pair of ever-growing incisors. Well-known rodents include mice, rats, squirrels, prairie dogs, porcupines, beavers, guinea pigs, and hamsters. Rabbits, hares, and pikas, whose i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Madagascar
Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa across the Mozambique Channel. At Madagascar is the world's List of island countries, second-largest island country, after Indonesia. The nation is home to around 30 million inhabitants and consists of the island of Geography of Madagascar, Madagascar (the List of islands by area, fourth-largest island in the world), along with numerous smaller peripheral islands. Following the prehistoric breakup of the supercontinent Gondwana, Madagascar split from the Indian subcontinent around 90 million years ago, allowing native plants and animals to evolve in relative isolation. Consequently, Madagascar is a biodiversity hotspot; over 90% of wildlife of Madagascar, its wildlife is endemic. Human settlement of Madagascar occurred during or befo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endangered Species
An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and invasive species. The International Union for Conservation of Nature (IUCN) Red List lists the global conservation status of many species, and various other agencies assess the status of species within particular areas. Many nations have laws that protect conservation-reliant species which, for example, forbid hunting, restrict land development, or create protected areas. Some endangered species are the target of extensive conservation efforts such as captive breeding and habitat restoration. Human activity is a significant cause in causing some species to become endangered. Conservation status The conservation status of a species indicates the likelihood that it will become extinct. Multiple factors are considered when assessing the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subfossil
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 absolute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxa Named By Alfred Grandidier
In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion. If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were set forth in Carl Linnaeus's system in '' Systema Naturae'', 10th edition (1758), as well as an unpublished work by Bernard and Antoine Laurent de Jussieu. The idea of a unit-based system of biological classification was first made widely available in 1805 in the i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
