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Caviomorph
Caviomorpha is the rodent infraorder or parvorder that unites all New World hystricognaths. It is supported by both fossil and molecular evidence. The Caviomorpha was for a time considered to be a separate order outside the Rodentia, but is now accepted as a genuine part of the rodents. Caviomorphs include the extinct Heptaxodontidae (giant hutias) and extant families of chinchilla rats, hutias, guinea pigs and the capybara, chinchillas and viscachas, tuco-tucos, agoutis, pacas, pacaranas, spiny rats, New World porcupines, coypu and octodonts (Vassallo and Antenucci, 2015). Origin The first known rodent fossils in South America are represented by the three taxa ''Cachiyacuy contamanensis'', ''C. kummeli'', and ''Canaanimys maquiensis'', as well as teeth from ''Eobranisamys'' sp. (Dasyproctidae) and ''Eospina'' sp., the latter two found also in the Santa Rosa fauna from the late Eocene or early Oligocene. By the late Oligocene, all superfamilies and most families of caviomo ... [...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] |
Hystricognath
The Hystricognathi are an infraorder of rodents, distinguished from other rodents by the bone structure of their skulls. The masseter medialis (a jaw muscle) passes partially through a hole below each eye socket (called the infraorbital foramen) and connects to the bone on the opposite side. This, together with their lack of an infraorbital plate and the relative size of the infraorbital foramen, distinguishes hystricognaths from other rodent groups. The 18 families within the Hystricognathi are divided into two parvorders, the Phiomorpha and the Caviomorpha. The Caviomorpha are mostly native to South America, with a few species in the Caribbean and North America, while the Phiomorpha occur in the Old World. Behavior Play behavior has been observed in seven hystricognath families. The caviomorphs chase each other, play-wrestle, and gallop. The longer-legged species chase more often than the shorter-legged species. They also rotate their heads and body muscles as a form of pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echimyidae
Echimyidae is the family of neotropical spiny rats and their fossil relatives. This is the most species-rich family of hystricognath rodents. It is probably also the most ecologically diverse, with members ranging from fully arboreal to terrestrial to fossorial to semiaquatic habits. They presently exist mainly in South America; three members of the family also range into Central America, and the hutias are found in the Greater Antilles in the Caribbean. Species of the extinct subfamily Heteropsomyinae formerly lived on Cuba, Hispaniola, and Puerto Rico in the Antilles, probably until the arrival of Europeans. Characteristics In general form, most spiny rats resemble rats, although they are more closely related to guinea pigs and chinchillas. Most species have stiff, pointed hairs, or spines, that presumably serve for protection from predators. Many echimyids can break off their tails when attacked. This action may confuse predators long enough for the spiny rat to es ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuco-tuco
A tuco-tuco is a neotropical rodent in the family Ctenomyidae.Parada, A., G. D’Elia, C.J. Bidau, and E.P. Lessa. 2011. Species Groups and the Evolutionary Diversification of Tuco-Tucos, genus ''Ctenomys'' (Rodentia: Ctenomyidae). ''Journal of Mammalogy'' 92(3): 671-682. Tuco-tucos belong to the only living genus of the family Ctenomyidae, ''Ctenomys'', but they include approximately 60 different species. The common name, "tuco-tuco" comes from the "tuc-tuc" sound they make while they dig their burrows.Anonymous. 2013. "Southern Tuco-tuco (''Ctenomys australis'')." ARKive. 04 Oct. 2013. http://www.arkive.org/southern-tuco-tuco/ctenomys-australis/ The relationships among the species are debated by taxonomists. It has been described that they are in a state of "taxonomic chaos", but banded karyotypes have been used to help make progress on their taxonomic study.Lessa, E. 1998. The Molecular Phylogenetics of Tuco-Tucos (genus ''Ctenomys'', Rodentia: Octodontidae) Suggests an Early ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capybara
The capybaraAlso called capivara (in Brazil), capiguara (in Bolivia), chigüire, chigüiro, or fercho (in Colombia and Venezuela), carpincho (in Argentina, Paraguay and Uruguay) and ronsoco (in Peru). or greater capybara (''Hydrochoerus hydrochaeris'') is a giant cavy rodent native to South America. It is the largest living rodent and a member of the genus ''Hydrochoerus''. The only other extant member is the lesser capybara (''Hydrochoerus isthmius''). Its close relatives include guinea pigs and rock cavies, and it is more distantly related to the agouti, the chinchilla, and the nutria. The capybara inhabits savannas and dense forests, and lives near bodies of water. It is a highly social species and can be found in groups as large as 100 individuals, but usually live in groups of 10–20 individuals. The capybara is hunted for its meat and hide and also for grease from its thick fatty skin. It is not considered a threatened species. Etymology Its common name is derived fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinchilla
Chinchillas are either of two species (''Chinchilla chinchilla'' and ''Chinchilla lanigera'') of crepuscular rodents of the parvorder Caviomorpha. They are slightly larger and more robust than ground squirrels, and are native to the Andes mountains in South America. They live in colonies called "herds" at high elevations up to . Historically, chinchillas lived in an area that included parts of Bolivia, Peru, Argentina, and Chile, but today, colonies in the wild are known only in Chile. Along with their relatives, viscachas, they make up the family Chinchillidae. They are also related to the chinchilla rat. The chinchilla has the densest fur of all mammals that live on land. In the water, the sea otter has a denser coat. The chinchilla is named after the Chincha people of the Andes, who once wore its dense, velvet-like fur. By the end of the 19th century, chinchillas had become quite rare after being hunted for their ultra-soft fur. Most chinchillas currently used by the fur ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinomyidae
The Dinomyidae are a family (biology), family of South American hystricognath rodents: the dinomyids were once a very speciose group, but now contains only a single living species, the pacarana. Several of the extinct dinomyids were among the largest rodents known to date; these included the bison-sized ''Josephoartigasia monesi'' and the smaller ''Josephoartigasia magna''. The dinomyids are thought to have occupied ecological niches associated with large grazing mammals due to their ability to compete with the Meridiungulata, native ungulates of South America. On the other side, they could feed on aquatic or swampy plants along the ancient rivers. These large forms disappeared after the formation of a Great American Interchange, connection to North America. The modern pacarana is only modest in size, considerably smaller than the capybara. The Neoepiblemidae, an entirely extinct family, may actually be part of the Dinomyidae; both groups are undoubtedly closely related. Genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heptaxodontidae
Heptaxodontidae, rarely called giant hutia, is an extinct family of large rodents known from fossil and subfossil material found in the West Indies. One species, ''Amblyrhiza inundata'', is estimated to have weighed between , reaching the weight of an eastern gorilla. This is twice as large as the capybara, the largest rodent living today, but still much smaller than ''Josephoartigasia monesi'', the largest rodent known. These animals were probably used as a food source by the pre-Columbian peoples of the Caribbean. Heptaxodontidae contains no living species and the grouping seems to be paraphyletic and arbitrary, however. One of the smaller species, ''Quemisia gravis'', may have survived as late as when the Spanish began to colonize the Caribbean. Despite the vernacular name, heptaxodontids are not closely related to the extant hutias of the family Echimyidae; Heptaxodontids are thought to be more closely related to the chinchillas. Taxonomy Heptaxodontidae is divided into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myocastoridae
Myocastorini is a tribe of echimyid rodents, proposed in 2017, and containing the five extant genera ''Callistomys'', ''Hoplomys'', ''Myocastor'', ''Proechimys'', and ''Thrichomys ''Thrichomys'' is a genus of South American rodents in the family Echimyidae. It contains at least five species, found in Bolivia, Brazil and Paraguay. They are as follows: * Common punaré (''Thrichomys apereoides'') * Foster's punaré (''Thri ...''. Definition Myocastorini members share long upper incisor roots (except ''Callistomys''), and mid- to long-sized lower incisor roots. These five genera share either four (''Callistomys'', ''Thrichomys'') or five (''Hoplomys'', ''Myocastor'', ''Proechimys'') lophids on the lower deciduous fourth premolar, three roots anchoring the upper molars, and well-connected lophs on cheek teeth. Members display a variety of lifestyles including terrestrial (''Hoplomys'', ''Proechimys'', ''Thrichomys''), arboreal (''Callistomys''), and amphibious (''Myocastor'') ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capybara
The capybaraAlso called capivara (in Brazil), capiguara (in Bolivia), chigüire, chigüiro, or fercho (in Colombia and Venezuela), carpincho (in Argentina, Paraguay and Uruguay) and ronsoco (in Peru). or greater capybara (''Hydrochoerus hydrochaeris'') is a giant cavy rodent native to South America. It is the largest living rodent and a member of the genus ''Hydrochoerus''. The only other extant member is the lesser capybara (''Hydrochoerus isthmius''). Its close relatives include guinea pigs and rock cavies, and it is more distantly related to the agouti, the chinchilla, and the nutria. The capybara inhabits savannas and dense forests, and lives near bodies of water. It is a highly social species and can be found in groups as large as 100 individuals, but usually live in groups of 10–20 individuals. The capybara is hunted for its meat and hide and also for grease from its thick fatty skin. It is not considered a threatened species. Etymology Its common name is derived fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossils
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] |
