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Squirrels - 2009-07-25 Mark Nichols 01
Squirrels are members of the family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrels. Squirrels are indigenous to the Americas, Eurasia, and Africa, and were introduced by humans to Australia. The earliest known fossilized squirrels date from the Eocene epoch, and among other living rodent families, the squirrels are most closely related to the mountain beaver and to the dormice. Etymology The word ''squirrel'', first attested in 1327, comes from the Anglo-Norman which is from the Old French , the reflex of a Latin word , which was taken from the Ancient Greek word (; from ) 'shadow-tailed', referring to the long bushy tail which many of its members have. The native Old English word for the squirrel, , survived only into Middle English (as ) before being replaced. The Old English word is of Common Germanic origin, cognate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), 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 Carbon-13, 13C in the atmosphere was exceptionally low in comparison with the more common isotope Carbon-12, 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 Popigai impact structure, Siberia and in what is now ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prairie Dog
Prairie dogs (genus ''Cynomys'') are herbivorous burrowing ground squirrels native to the grasslands of North America. Within the genus are five species: black-tailed, white-tailed, Gunnison's, Utah, and Mexican prairie dogs. In Mexico, prairie dogs are found primarily in the northern states, which lie at the southern end of the Great Plains: northeastern Sonora, north and northeastern Chihuahua, northern Coahuila, northern Nuevo León, and northern Tamaulipas. In the United States, they range primarily to the west of the Mississippi River, though they have also been introduced in a few eastern locales. They are also found in the Canadian Prairies. Despite the name, they are not actually canines; prairie dogs, along with the marmots, chipmunks, and several other basal genera belong to the ground squirrels (tribe ''Marmotini''), part of the larger squirrel family (''Sciuridae''). Prairie dogs are considered a keystone species with their mounds often being used by other s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chipmunk
Chipmunks are small, striped rodents of the family Sciuridae. Chipmunks are found in North America, with the exception of the Siberian chipmunk which is found primarily in Asia. Taxonomy and systematics Chipmunks may be classified either as a single genus, ''Tamias'', or as three genera: ''Tamias'', of which the eastern chipmunk (''T. striatus'') is the only living member; ''Eutamias'', of which the Siberian chipmunk (''E. sibiricus'') is the only living member; and ''Neotamias'', which includes the 23 remaining, mostly western North American, species. These classifications were treated as subgenera due to the chipmunks' morphological similarities. As a result, most taxonomies over the twentieth century have placed the chipmunks into a single genus. However, studies of mitochondrial DNA show that the divergence between each of the three chipmunk groups is comparable to the genetic differences between ''Marmota'' and ''Spermophilus'', so the three genera classifications have b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ground Squirrel
Ground squirrels are members of the squirrel family of rodents (Sciuridae), which generally live on or in the ground, rather than trees. The term is most often used for the medium-sized ground squirrels, as the larger ones are more commonly known as marmots (genus ''Marmota'') or prairie dogs, while the smaller and less bushy-tailed ground squirrels tend to be known as chipmunks (genus ''Tamias''). Together, they make up the "marmot tribe" of squirrels, Marmotini, a division within the large and mainly ground squirrel subfamily Xerinae, and containing six living genera. Well-known members of this largely Holarctic group are the marmots (''Marmota''), including the American groundhog, the chipmunks, the susliks (''Spermophilus''), and the prairie dogs (''Cynomys''). They are highly variable in size and habitus, but most are remarkably able to rise up on their hind legs and stand fully erect comfortably for prolonged periods. They also tend to be far more gregarious than other sq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tree Squirrel
Tree squirrels are the members of the squirrel Family (biology), family (Sciuridae) commonly just referred to as "squirrels." They include more than 100 arboreal species native to all continents except Antarctica and Oceania. They do not form a single natural, or monophyly, monophyletic, group; they are variously related to others in the squirrel family, including ground squirrels, flying squirrels, marmots, and chipmunks. The defining characteristic used to determine which species of Sciuridae are tree squirrels is dependent on their habitat rather than their physiology. Tree squirrels live mostly among trees, as opposed to those that live in burrows in the ground or among rocks. An exception is the flying squirrel that also makes its home in trees, but has a physiological distinction separating it from its tree squirrel cousins: special flaps of skin called patagia, acting as glider wings, which allow gliding flight. The best known genus of tree squirrels is ''Sciurus'', which ... [...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] |
Family (biology)
Family ( la, familia, plural ') is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". What belongs to a family—or if a described family should be recognized at all—are proposed and determined by practicing taxonomists. There are no hard rules for describing or recognizing a family, but in plants, they can be characterized on the basis of both vegetative and reproductive features of plant species. Taxonomists often take different positions about descriptions, and there may be no broad consensus across the scientific community for some time. The publishing of new data and opini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protoxerini
The Protoxerini comprise a tribe of squirrels found in Africa. The 30 species in six genera are:Thorington, R. W. and R. S. Hoffmann. 2005. Family Sciuridae. Pp 754–818 in Mammal Species of the World A Taxonomic and Geographic Reference. Johns Hopkins University Press, Baltimore. *''Epixerus'' (monotypic) - Ebian's palm squirrel *'' Funisciurus'' (nine species) - African striped squirrels *'' Heliosciurus'' (six species) - sun squirrels *''Myosciurus The African pygmy squirrel (''Myosciurus pumilio'') is a species of rodent in the family Sciuridae. It is monotypic within the genus ''Myosciurus''. It is found in tropical rainforests in Cameroon, the Republic of the Congo, Equatorial Guinea, ...'' (monotypic) - African pygmy squirrel *'' Paraxerus'' (11 species) - African bush squirrels *'' Protoxerus'' (two species) - African giant squirrels References Protoxerini Mammal tribes {{Squirrel-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xerini
Xerini is a tribe of ground squirrels occurring in Africa and Asia. With the tribes Marmotini (Holarctic ground squirrels) and Protoxerini (African tree squirrels), they form the subfamily Xerinae. There are five living genera—'' Xerus'', the unstriped ground squirrel; '' Euxerus'', the striped ground squirrel; ''Geosciurus'', the Cape and mountain ground squirrels; ''Atlantoxerus'', containing the living Barbary ground squirrel of North Africa and some extinct species; and ''Spermophilopsis'', containing the long-clawed ground squirrel of Central Asia. The squirrels live in open woodlands, grasslands, or rocky country. They are diurnal and terrestrial, living in burrows. Their diet is roots, seeds, fruits, pods, grains, insects, small vertebrates and bird eggs. They live in colonies similar to North American prairie dogs, and have similar behavior. If kept as pets, they run free as house cats do, otherwise farmers consider them pests. Breeding in South African ground squirrels ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xerinae
The Xerinae comprise a subfamily of squirrels, many of which are highly terrestrial. It includes the tribes Marmotini (marmots, chipmunks, prairie dogs, and other Holarctic ground squirrels), Xerini (African and some Eurasian ground squirrels), and Protoxerini (African tree squirrels).Thorington, R. W. and R. S. Hoffmann (2005). "Family Sciuridae". pp. 754–818 in Wilson, E. D. and Reeder, D. M. (eds.), Mammal Species of the World: A Taxonomic and Geographic Reference', Vol. 2. Johns Hopkins University Press, Baltimore. Taxonomy Tribe Xerini six species of ground squirrels in five genera, occurring in Africa and Asia. :''Atlantoxerus'' :'' Euxerus'' :''Geosciurus'' :''Spermophilopsis'' :'' Xerus'' Tribe Protoxerini thirty species of tree squirrels in six genera, occurring in Africa. :''Epixerus'' :'' Funisciurus'' :'' Heliosciurus'' :''Myosciurus'' :'' Paraxerus'' :'' Protoxerus'' Tribe Marmotini ground squirrels in fifteen genera, occurring world wide. Includes the prairie d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
