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List Of Mammals Of Madagascar
This is a list of the native wild mammal species recorded in Madagascar. As of June 2014 (following the IUCN reassessment of the lemurs) there are 241 extant mammal species recognized in Madagascar, of which 22 are critically endangered, 62 are endangered, 32 are vulnerable, 9 are near threatened, 72 are of least concern and 44 are either data deficient or not evaluated. All of the critically endangered species are lemurs. The mammalian fauna of Madagascar is highly distinctive and largely endemic. The extant nonmarine, nonchiropteran taxa constitute (as of June 2014) 168 species, 40 genera and 9 families; of these, besides a probably introduced shrew, endemic taxa make up all the species, all the genera, and all but one of the families. This endemic terrestrial fauna, consisting of lemurs, tenrecs, nesomyine rodents and euplerid carnivorans, is thought to have colonized the island from Africa via four (or five, if aye-ayes arrived separately) rafting events. The other historic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extant Taxon
Neontology is a part of biology that, in contrast to paleontology, deals with living (or, more generally, '' recent'') organisms. It is the study of extant taxa (singular: extant taxon): taxa (such as species, genera and families) with members still alive, as opposed to (all) being extinct. For example: * The moose (''Alces alces'') is an extant species, and the dodo (''Raphus cucullatus'') is an extinct species. * In the group of molluscs known as the cephalopods, there were approximately 600 extant species and 7,500 extinct species. A taxon can be classified as extinct if it is broadly agreed or certified that no members of the group are still alive. Conversely, an extinct taxon can be reclassified as extant if there are new discoveries of living species ("Lazarus species"), or if previously-known extant species are reclassified as members of the taxon. Most biologists, zoologists, and botanists are in practice neontologists, and the term neontologist is used large ... [...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] |
Vicariance
Allopatric speciation () – also referred to as geographic speciation, vicariant speciation, or its earlier name the dumbbell model – is a mode of speciation that occurs when biological populations become geographically isolated from each other to an extent that prevents or interferes with gene flow. Various geographic changes can arise such as the movement of continents, and the formation of mountains, islands, bodies of water, or glaciers. Human activity such as agriculture or developments can also change the distribution of species populations. These factors can substantially alter a region's geography, resulting in the separation of a species population into isolated subpopulations. The vicariant populations then undergo genetic changes as they become subjected to different selective pressures, experience genetic drift, and accumulate different mutations in the separated populations' gene pools. The barriers prevent the exchange of genetic information between ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ratite
A ratite () is any of a diverse group of flightless, large, long-necked, and long-legged birds of the infraclass Palaeognathae. Kiwi, the exception, are much smaller and shorter-legged and are the only nocturnal extant ratites. The systematics of and relationships within the paleognath clade have been in flux. Previously, all the flightless members had been assigned to the order Struthioniformes, which is more recently regarded as containing only the ostrich. The modern bird superorder Palaeognathae consists of ratites and the flighted Neotropic tinamous (compare to Neognathae). Unlike other flightless birds, the ratites have no keel on their sternum — hence the name, from the Latin ''ratis'' (raft, a vessel which has no keel - in contradistinction to extant flighted birds with a keel). Without this to anchor their wing muscles, they could not have flown even if they developed suitable wings. Ratites are a paraphyletic group; tinamous fall within them, and are the sister gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elephant Bird
Elephant birds are members of the extinct ratite family Aepyornithidae, made up of flightless birds that once lived on the island of Madagascar. They are thought to have become extinct around 1000-1200 CE, probably as a result of human activity. Elephant birds comprised the genera ''Mullerornis'', ''Vorombe'' and ''Aepyornis''. While they were in close geographical proximity to the ostrich, their closest living relatives are kiwi (found only in New Zealand), suggesting that ratites did not diversify by vicariance during the breakup of Gondwana but instead evolved from ancestors that dispersed more recently by flying. In September 2018, scientists determined that ''Vorombe titan'' reached weights of and stood tall, making it the world's largest and heaviest bird, slightly larger than the much older ''Dromornis stirtoni''. Other members of the family were also very large, exhibiting the phenomenon of island gigantism. Description Elephant birds have been extinct since at lea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaeoindris
''Archaeoindris fontoynontii'' is an extinct giant lemur and the largest primate known to have evolved on Madagascar, comparable in size to a male gorilla. It belonged to a family of extinct lemurs known as "sloth lemurs" (Palaeopropithecidae) and, because of its extremely large size, it has been compared to the ground sloths that once roamed North and South America. It was most closely related to ''Palaeopropithecus'', the second largest type of sloth lemur. Along with the other sloth lemurs, ''Archaeoindris'' was related to the living indri, sifakas, and woolly lemurs, as well as the recently extinct monkey lemurs (Archaeolemuridae). The genus, ''Archaeoindris'', translates to "ancient indri-like lemur", even though it probably became extinct recently, around 350 BCE. ''Archaeoindris'' was first described by Herbert F. Standing in 1909 based on subfossil fragmentary jaws, although Charles Lamberton later discovered a complete skull. Only six bones from the lower skeleton have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megafauna
In terrestrial zoology, the megafauna (from Greek μέγας ''megas'' "large" and New Latin ''fauna'' "animal life") comprises the large or giant animals of an area, habitat, or geological period, extinct and/or extant. The most common thresholds used are weight over see page 17 (i.e., having a mass comparable to or larger than a human) or over a tonne, (i.e., having a mass comparable to or larger than an ox). The first of these include many species not popularly thought of as overly large, and being the only few large animals left in a given range/area, such as white-tailed deer, Thomson's gazelle, and red kangaroo. In practice, the most common usage encountered in academic and popular writing describes land mammals roughly larger than a human that are not (solely) domesticated. The term is especially associated with the Pleistocene megafauna – the land animals often larger than their extant counterparts that are considered archetypical of the last ice age, such as mammoth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artiodactyla (even-toed Ungulates And Cetaceans)
The even-toed ungulates (Artiodactyla , ) are ungulates—hoofed animals—which bear weight equally on two (an even number) of their five toes: the third and fourth. The other three toes are either present, absent, vestigial, or pointing posteriorly. By contrast, odd-toed ungulates bear weight on an odd number of the five toes. Another difference between the two is that many other even-toed ungulates (with the exception of Suina) digest plant cellulose in one or more stomach chambers rather than in their intestine as the odd-toed ungulates do. Cetaceans (whales, dolphins, and porpoises) evolved from even-toed ungulates, and are therefore often classified under the same taxonomic branch because a species cannot outgrow its evolutionary ancestry; some modern taxonomists combine the two under the name Cetartiodactyla , while others opt to include cetaceans in the already-existing Artiodactyla. The roughly 270 land-based even-toed ungulate species include pigs, peccaries, hippopota ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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