Mountain Beaver Fossil range: Late Pleistocene - Recent
Conservation status
Near Threatened
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Rodentia Family: Aplodontiidae Brandt, 1855 Genus: Aplodontia Richardson, 1829 Species: A. rufa
Binomial name
Aplodontia rufa (Rafinesque, 1817)

The Mountain Beaver (Aplodontia rufa) is a primitive rodent unrelated to beavers and not usually found in mountainous areas. It has several common names including Aplodontia, Boomer, Ground Bear, and Giant Mole. The name Sewellel or Suwellel is a First Nations/Native American name . This species is the only member of its genus, Aplodontia, and family, Aplodontiidae. The Pleistocene epoch (IPA: ) is part of the geologic timescale. ... Wikipedia does not have an article with this exact name. ... The conservation status of a species is an indicator of the likelihood of that species continuing to survive either in the present day or the future. ... Image File history File links Status_iucn2. ... Near Threatened (NT) is an conservation status assigned to species or lower taxa which may be considered threatened with extinction in the near future, although it does not currently qualify for the threatened status. ... Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ... For other uses, see Animal (disambiguation). ... Typical Classes See below Chordates (phylum Chordata) are a group of animals that includes the vertebrates, together with several closely related invertebrates. ... Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria Mammals (class Mammalia) are warm-blooded, vertebrate animals characterized by the production of milk in female mammary glands and by the presence of: hair, three middle ear bones used in hearing, and a neocortex region in... Suborders Sciuromorpha Castorimorpha Myomorpha Anomaluromorpha Hystricomorpha Rodentia is an order of mammals also known as rodents. ... Johann Friedrich von Brandt (May 25, 1802 - July 15, 1879) was a German naturalist. ... This article does not cite any references or sources. ... Suborders Sciuromorpha Castorimorpha Myomorpha Anomaluromorpha Hystricomorpha Rodentia is an order of mammals also known as rodents. ... Species C. canadensis C. fiber Beavers are semi-aquatic rodents native to North America and Europe. ... Lyskamm, 4 527 m, Pennine Alps A mountain is a landform that extends above the surrounding terrain in a limited area. ... First Nations is a term of ethnicity used in Canada. ... Native Americans (also Indians, Aboriginal Peoples, American Indians, First Nations, Alaskan Natives, Amerindians, or Indigenous Peoples of America) are the indigenous inhabitants of The Americas prior to the European colonization, and their modern descendants. ...

Characteristics

Mountain Beavers are brown in color, but fur can range from slightly more reddish or blackish depending on subspecies. There is a light patch under each ear. The animals have distinctively short tails. Adults weigh between about 500-900 g with a few specimens topping 1,000 g. Total length is about 30-50 cm with a tail length equal to 1-4 cm.

The skull is protrogomorphous. This means that it has no specialized attachments for the masseter muscles as seen in other rodents. It is flattened and lacks a postorbital process. The baculum is thin and distinctly forked. The penis is about 4.5 cm in length. They do not have a true scrotum, but testes move into a position called semiscrotal during the breeding season. It has been suggested that temporal fenestra be merged into this article or section. ... The zygomasseteric system (or zygomasseteric structure) in rodents is the anatomical arrangement of the masseter muscle of the jaw and the zygomatic arch of the skull. ... In human anatomy, the masseter is one of the muscles of mastication. ... The baculum (also penis bone, penile bone or os penis) is a bone found in the penis of most mammals. ... The penis (plural penises, penes) is an external male sexual organ. ... In some male mammals, the scrotum is a protuberance of skin and muscle containing the testicles. ... Human male anatomy The testicles, known medically as testes (singular testis), are the male generative glands in animals. ... Reproduction is the creation of one thing as a copy of, product of, or replacement for a similar thing, e. ...

Mountain Beavers have an unusual projection on each molar and premolar which is unique among mammals and allows for easy identification of teeth. This projection points toward the cheek on the upper toothrow, but points toward the tongue on the lower. The cheek teeth lack the complex folds of other rodents and are instead comprised of a single basin. They are hypsodont and ever-growing. Two upper and one lower premolars are present. All three upper and lower molars are also present. Molars are the rearmost and most complicated kind of tooth in most mammals. ... The premolar teeth or bicuspids are transitional teeth located between the canine and molar teeth. ... The mandible (from Latin mandibÅ­la, jawbone) or inferior maxillary bone is, together with the maxilla, the largest and strongest bone of the face. ... Especially high-crowned teeth, which provides lots of extra material for wear and tear. ...

Mountain Beavers cannot produce concentrated urine. They are thought to be physiologically restricted to the temperate rain forest regions of the North American Pacific coast due to their inability to obtain sufficient water in more arid environments. Their karyotype is 2n=46. This article does not cite any references or sources. ... This article or section is in need of attention from an expert on the subject. ... Temperate rain forest in the Mount Hood Wilderness, Oregon, United States. ... Karyogram of human male using Giemsa staining. ...

Habits and distribution

Mountain Beavers are found in coastal areas of the Pacific Northwest of North America. These are usually low elevation regions, but they can occasionally be seen as high as tree line. They can be found in both deciduous and coniferous forests, but appear to prefer the former. These animals appear to be physiologically limited to moist regions with minimal snowfall and cool winters. They do not appear to be able to conserve body heat or warmth as efficiently as other rodents. They do not hibernate. The Pacific Northwest from space This page is about the region that includes parts of Canada and the United States. ... North America North America is a continent[1] in the Earths northern hemisphere and (chiefly) western hemisphere. ... In this view of an alpine tree-line, the distant line looks particularly sharp. ... Deciduous means temporary or tending to fall off (deriving from the Latin word decidere, to fall off). ... Temperate coniferous forests are a terrestrial biome found in temperate regions of the world with warm summers and cool winters and adequate rainfall to sustain a forest. ... This article refers to the process of hibernation in biology. ...

Mountain Beavers build elaborate burrow systems with chambers devoted to fecal and food caches. They exhibit coprophagy and eat soft fecal pellets to obtain maximum nutrients. Hard fecal pellets are transferred to fecal chambers using their incisors. Food includes fleshy herbs and young shoots of more woody plants. Ferns probably make up the bulk of the diet. They appear to be strictly vegetarian. Their consumption of seedling trees has led some to consider them a pest. They appear to build hay mounds at some burrow entrances, but whether this behavior is related to water regulation, curing food, or gathering nest materials is debated. Coprophagia is the consumption of feces. ... Feces, faeces, or fæces (see spelling differences) In humans, defecation may occur (depending on the individual and the circumstances) from once every two or three days to several times a day. ... Classes Psilotopsida Equisetopsida Marattiopsida Pteridopsida (Polypodiopsida) this dnt make sense A fern is any one of a group of about 20,000 species of plants classified in the phylum or division Pteridophyta, also known as Filicophyta. ... In zoology, an herbivore is an animal that is adapted to eat primarily plants (rather than meat). ... Stacked hay in Romania Haystacks on stilts in Paddy fields, North Kanara, India Hay is dried grass or legumes cut, stored, and used for animal feed, particularly for grazing animals like cattle, horses, goats and sheep. ...

A host of other animals have been documented within the burrow system of Mountain Beavers. These include: Long-tailed Weasels, Ermines, Minks, Fishers, American Badgers, raccoons, Western Spotted Skunks, Striped Skunks, Brush Rabbits, Snowshoe Hares, Douglas Squirrels, Western Jumping Mice, Water Voles, California Voles, White-footed Voles, Western Red-backed Voles, Deer Mice, Bushy-tailed Woodrats, Dusky-footed Woodrats, Botta's Pocket Gopher, American Shrew Moles, Coast Moles, and Pacific Giant Salamanders (Carraway and Verts, 1993). Because of their effect on such a wide variety of plants and animals, some ecologists consider Mountain Beavers to be keystone species. Binomial name Mustela frenata Lichtenstein, 1831 The Long-tailed Weasel (Mustela frenata) is the most widely distributed mustelid in the New World. ... Binomial name Linnaeus, 1758 Range map The stoat (Mustela erminea) is a small mammal of the family Mustelidae. ... Binomial name Mustela vison (Schreber, 1777) The American Mink, Mustela vison, is a North American member of the Mustelidae family found in Alaska, Canada and most of the United States. ... Binomial name (Erxleben, 1777) The fisher is a North American marten, a medium sized mustelid. ... Binomial name Taxidea taxus (Schreber, 1777) The American Badger, Taxidea taxus, is a North American badger, somewhat similar in appearance to the European Badger. ... Binomial name (Linnaeus, 1758) Common Raccoon native range in red, feral range in blue. ... Binomial name Spilogale gracilis The Western Spotted Skunk (Spilogale gracilis) is a spotted skunk found throughout the western United States, northern Mexico, and southwestern British Columbia. ... Binomial name Schreber, 1776 The Striped Skunk, Mephitis mephitis, is an omnivorous mammal of the skunk family Mephitidae. ... Binomial name Sylvilagus bachmani (Waterhouse, 1839) The Brush Rabbit (Sylvilagus bachmani), or Western Brush Rabbit, is a species of cottontail rabbit found in western coastal regions of North America, from the Columbia River in Oregon to the southern tip of the Baja California peninsula. ... Binomial name Lepus americanus Erxleben, 1777 The Snowshoe Hare (Lepus americanus) is a species of hare found in North America. ... Binomial name Tamiasciurus douglasii (Bachman, 1839) Desolation Wilderness (Sierra Nevada) The Douglas Squirrel, Tamiasciurus douglasii, is a pine squirrel found in the Pacific coastal states and provinces of North America. ... Binomial name Microtus richardsoni (De Kay, 1842) The Water Vole, Microtus richardsoni or Arvicola richardsoni, is the largest North American vole. ... Binomial name (Peale, 1848) The California Vole (Microtus californicus) is a type of vole which lives throughout much of California and some southwestern Oregon. ... Binomial name Peromyscus maniculatus (Wagner, 1845) Peromyscus maniculatus is rodent native to North America. ... Binomial name Ord, 1815 The Bushy-Talied Woodrat, Packrat, or Woodrat (Neotoma cinerea) is a species of rodent in the Muridae family. ... Binomial name Baird, 1858 The Dusky-Footed Woodrat (Neotoma fuscipes) is a species of rodent in the Muridae family. ... Binomial name Thomomys bottae (Eydoux and Gervais, 1836) Bottas pocket gopher (Thomomys bottae) is a pocket gopher native to western North America, from California east to Texas and from southern Utah and Colorado south to Mexico. ... Binomial name Neurotrichus gibbsii (Baird, 1857) The American shrew mole, Neurotrichus gibbsii, is the smallest North American mole. ... Binomial name Scapanus orarius (True, 1896) The Coast Mole or Pacific Mole, Scapanus orarius, is a medium-sized North American mole. ... Species Dicamptodon aterrimus Dicamptodon copei Dicamptodon ensatus Dicamptodon tenebrosus The Pacific giant salamanders (Dicamptodontidae) are a family of large salamanders. ... Ecology is the branch of science that studies the distribution and abundance of living organisms, and the interactions between organisms and their environment. ... This article or section does not cite its references or sources. ...

Known predators include Bobcats, Coyotes, Cougars, Golden Eagles, and Owls. Among the parasites of the Mountain Beaver is the largest flea known to modern science, Hystrichopsylla schefferi. Females of this flea can be 8 mm long. Binomial name (Schreber, 1777) The Bobcat (Lynx rufus) is a North American mammal of the cat family, Felidae. ... Binomial name Say, 1823 Coyote range The coyote (Canis latrans, meaning barking dog) also prairie wolf [2]) is a member of the Canidae (dog) family and a close relative of the Gray Wolf. ... For other uses, see Cougar (disambiguation). ... Binomial name Aquila chrysaetos Linnaeus, 1758 World distribution of the golden eagle Light green = Nesting area Blue = Wintering area Dark green = All year distribution The Golden Eagle (Aquila chrysaetos) is one of the best known birds of prey in the Northern Hemisphere. ... Families Strigidae Tytonidae Ogygoptyngidae (fossil) Palaeoglaucidae (fossil) Protostrigidae (fossil) Sophiornithidae (fossil) Synonyms Strigidae sensu Sibley & Ahlquist Owls are a group of birds of prey. ... Families Tungidae â€“ sticktight and chigoe fleas (chiggers) Pulicidae â€“ common fleas Coptopsyllidae Vermipsyllidae â€“ carnivore fleas Rhopalopsyllidae â€“ marsupial fleas Hypsophthalmidae Stephanocircidae Pygiopsyllidae Hystrichopsyllidae â€“ rat and mouse fleas Leptopsyllidae â€“ mouse and rat fleas Ischnopsyllidae â€“ bat fleas Ceratophyllidae:-fleas mainly associated with rodents Amphipsyllidae Malacopsyllidae Dolichopsyllidae â€“ rodent fleas Ctenopsyllidae Flea is the common name...

The breeding season is between January-March with 2-3 young born February-April. The young are born hairless, pink, and blind. Longevity is 5-10 years, fairly long as rodents go. They are not social, though home ranges can overlap. Longevity is defined as long life or the length of a persons life (life expectancy). ...

Mountain Beavers are capable of climbing trees, but rarely travel far from burrows. The thumb is slightly opposable and the animals will sit on their hindquarters and manipulate food with their forelimbs and incisors. // This digit is one of the five fingers (though the word finger can also refer exclusively to the non-thumb digits). ... Missing image Thumbs up In human anatomy, the thumb is the first digit on a hand. ... Look up ARM in Wiktionary, the free dictionary. ...

Spelling and etymology

Most references use the spelling Aplodontidae for the family name. This has been deemed incorrect due to the technical rules of converting a genus name into a family name. The proper conversion of Aplodontia to a family name is to drop the -a only and add -idae. Thus, Aplodontiidae is technically correct. This spelling is gaining acceptance in modern texts.

Alternate spellings of the genus name have also been reported, with as many as 30 variants historically. These include Haplodontia, Haplodon, Aploodontia, Apluodontia, and Aplodontie among others. The name Aplodontia means "simple tooth" and is in reference to the single large basin comprising the bulk of each cheek tooth. The specific epithet, rufa means red or reddish. A specific epithet is a biological epithet of a species. ...

Subspecies

At present seven subspecies of Aplodontia rufa are recognized. This article is about the zoological term. ...

A. r. californica

A. r. californica (Peters, 1864) is distributed throughout the Sierra Nevada range in Northern California. The Sierra Nevada (Spanish for Snowy Range) is a mountain range that is almost entirely in the eastern portion of the U.S. state of California. ... Northern California, sometimes referred to as NorCal, is the northern portion of the U.S. state of California. ...

A. r. humboldtiana

A. r. humboldtiana Taylor, 1916 is restricted to the far Northwestern coast of California. Official language(s) English Capital Sacramento Largest city Los Angeles Area  Ranked 3rd  - Total 158,302 sq mi (410,000 km²)  - Width 250 miles (400 km)  - Length 770 miles (1,240 km)  - % water 4. ...

A. r. nigra

A. r. nigra Taylor, 1914 is restricted to a small region in southern Mendocino County, California. Islands off Mendocino A Beach in the City of Elk Mendocino County is a county located on the north coast of the U.S. state of California, north of the San Francisco Bay Area and Sonoma County and west of the Central Valley. ...

A. r. pacifica

A. r. pacifica Merriam, 1899 is distributed across coastal Oregon. Official language(s) (none)[1] Capital Salem Largest city Portland Area  Ranked 9th  - Total 98,466 sq mi (255,026 km²)  - Width 260 miles (420 km)  - Length 360 miles (580 km)  - % water 2. ...

A. r. phaea

A. r. phaea Merriam, 1899 is found in a small pocket just Northwest of San Francisco, California. Nickname: Location of the City and County of San Francisco, California Coordinates: , Country United States of America State California City-County San Francisco Founded 1776 Government  - Mayor Gavin Newsom Area  - City  47 sq mi (122 km²)  - Land  46. ...

A. r. rainieri

A. r. rainieri Merriam, 1899 is found across the Cascade Range from southern British Columbia to northern California. Mount Jefferson in Oregon. ... Motto: Splendor Sine Occasu (Latin: Splendour without diminishment) Capital Victoria Largest city Vancouver Official languages English Government - Lieutenant-Governor Iona Campagnolo - Premier Gordon Campbell (BC Liberal) Federal representation in Canadian Parliament - House seats 36 - Senate seats 6 Confederation July 20, 1871 (6th province) Area  Ranked 4th - Total 944,735 km... Official language(s) English Capital Sacramento Largest city Los Angeles Area  Ranked 3rd  - Total 158,302 sq mi (410,000 km²)  - Width 250 miles (400 km)  - Length 770 miles (1,240 km)  - % water 4. ...

A. r. rufa

A. r. rufa (Rafinesque, 1817), the type of the species, is found along coastal Washington, particularly on the Olympic Peninsula. Official language(s) English Capital Olympia Largest city Seattle Area  Ranked 18th  - Total 71,342 sq mi (184,827 km²)  - Width 240 miles (385 km)  - Length 360 miles (580 km)  - % water 6. ... The Olympic Peninsula is the large arm of land in western Washington state that lies across Puget Sound from Seattle. ...

Closest relatives

The Mountain Beaver is considered a living fossil by many researchers due to the presence of a host of primitive characters, particularly the protrogomorphous zygomasseteric system. This condition is similar to what is found in most mammal groups, such as rabbits, where no extreme specialization of the masseter muscle has evolved. In the protrogomorphous condition, the masseter muscle does not pass through the infraorbital foramen as it does in guinea pigs and mice. Likewise, the medial masseter muscle attaches to the base of the zygomatic arch and does not extend to the region in front of the eye as is seen in squirrels and mice. The Mountain Beaver is the only living rodent with this primitive cranial and muscular feature (except perhaps the blesmols who clearly evolved protrogomorphy from a hystricomorphous ancestor). The Mountain Beaver was once thought to be related to the earliest protrogomorphous rodents such as the ischyromyids like Paramys. Both molecular and morphological phylogeneticists have recently suggested a more distant relationship to these animals. This article or section does not adequately cite its references or sources. ... This cladogram shows the relationship among various insect groups. ... The zygomasseteric system (or zygomasseteric structure) in rodents is the anatomical arrangement of the masseter muscle of the jaw and the zygomatic arch of the skull. ... The zygomasseteric system (or zygomasseteric structure) in rodents is the anatomical arrangement of the masseter muscle of the jaw and the zygomatic arch of the skull. ... Genera Pentalagus Bunolagus Nesolagus Romerolagus Brachylagus Sylvilagus Oryctolagus Poelagus Rabbits are small mammals in the family Leporidae of the order Lagomorpha, found in several parts of the world. ... In human anatomy, the masseter is one of the muscles of mastication. ... Above the canine fossa is the infraorbital foramen, the end of the infraorbital canal; it transmits the infraorbital vessels and nerve. ... Binomial name Cavia porcellus (Linnaeus, 1758) Guinea pigs (also called cavies) are rodents belonging to the family Caviidae and the genus Cavia, originally indigenous to the Andes. ... Feral mouse A mouse (plural mice) is a rodent that belongs to one of numerous species of small mammals. ... The zygomatic bone (also known as the zygoma; Os Zygomaticum; Malar Bone) is a paired bone of the human skull. ... Genera Many, see the article Sciuridae. ... Genera Georychus Cryptomys Heliophobius Bathyergus Heterocephalus The blesmols, also known as mole rats, or African mole-rats, are burrowing rodents of the family Bathyergidae. ... A type of rodent zygomasseteric system where the infraorbital foramen, which runs from the anterior part of the orbit to the outside of the rostrum, becomes very large. ... Species Paramus is an extinct genus of rodent from North America, Europe, and Asia. ... Molecular phylogeny is the use of the structure of molecules to gain information on an organisms evolutionary relationships. ... Phylogenetic groups, or taxa, can be monophyletic, paraphyletic, or polyphyletic. ...

Molecular results have consistently produced a sister relationship between the Mountain Beaver and the squirrels (family Sciuridae). This clade is referred to as Sciuroidea, Sciuromorpha (not to be confused with the sciuromorphous zygomasseteric system), or Sciurida depending on the author. Genera Many, see the article Sciuridae. ... Genera Many: see text. ... A clade is a term belonging to the discipline of cladistics. ... Families †Allomyidae Aplodontiidae †Mylagaulidae Sciuridae †Reithroparamyidae Gliridae Skull of an Oriental giant squirrel displaying a sciuromorphous zygomatic system. ... Infraorders Anomaluromorpha Castorimorpha Ctenodactylomorpha Geomorpha Glirimorpha Myodonta Sciurida Sciurognathi is a suborder of rodents that includes squirrels, chipmunks, beavers, and many types of mice. ... The zygomasseteric system (or zygomasseteric structure) in rodents is the anatomical arrangement of the masseter muscle of the jaw and the zygomatic arch of the skull. ... Families †Allomyidae Aplodontiidae †Mylagaulidae Sciuridae †Reithroparamyidae Gliridae Skull of an Oriental giant squirrel displaying a sciuromorphous zygomatic system. ...

According to the fossil record, the Aplodontoidea split from the squirrels in the Middle or Late Eocene as indicated by the extinct genera †Spurimus and †Prosciurus. The fossil record for the genus Aplodontia itself extends to the Late Pleistocene of North America. FOSSIL is a standard for allowing serial communication for telecommunications programs under DOS. FOSSIL is an acronym for Fido Opus Seadog Standard Interface Layer. ... hfajhfiudshfas == == == --24. ... The Pleistocene epoch (IPA: ) is part of the geologic timescale. ...

References

• Steele (2000). Aplodontia rufa. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006. Database entry includes a brief justification of why this species is near threatened

• Adkins, R. M. E. L. Gelke, D. Rowe, and R. L. Honeycutt. 2001. Molecular phylogeny and divergence time estimates for major rodent groups: Evidence from multiple genes. Molecular Biology and Evolution, 18:777-791.

• Carraway, L. N. and B. J. Verts. 1993. Aplodontia rufa. Mammalian Species, 431:1-10.

• MacDonald, D. ed. 1987. The Encyclopedia of Mammals. Facts on File Publications, New York.

• McKenna, Malcolm C., and Bell, Susan K. 1997. Classification of Mammals Above the Species Level. Columbia University Press, New York, 631 pp. ISBN 0-231-11013-8

• Nowak, R. M. 1999. Walker's Mammals of the World, Vol. 2. Johns Hopkins University Press, London.