Mieko Nakamura, a retired martial arts equipment supplier and former Playboy bunny in Denver in the late 1960s, recently joined about 120 other former bunnies in. Local Escorts and Adult Entertainment Services - West Virginia. Meet like minded singles, couples and group at SLS.com, the premiere alternative lifestyle dating community for the adventurous. Sign up for free! AFSCME Ohio Council 8 is standing up to Republicans in the Legislature who want to balance the state budget on the backs of Ohio’s college and university employees. Niall Horan, 23, revealed that he has been so busy recording his debut solo album he's had little time for a love life. The One D heartthrob admitted he barely even. Rodent - Wikipedia. Rodents. Temporal range: 5. Ma. Late Paleocene–Holocene. Clockwise from top left: capybara, springhare, golden- mantled ground squirrel, house mouse and beaver representing the suborders Hystricomorpha, Anomaluromorpha, Sciuromorpha, Myomorpha, and Castorimorpha, respectively. Scientific classification. Kingdom: Animalia. Phylum: Chordata. Class: Mammalia(unranked): Glires. News, Photos and Information about Chicago Tribune. Popular Topics. Join Classmates.com for Free! Reconnect with high school friends, browse the biggest database of online yearbooks and/or plan high school reunions. Species Maximum longevity years (. Gestation days. Litters per year. Litter size average (range) House mouse (Mus musculus) 4.0. ![]() Order: Rodentia. Bowdich, 1. Suborders. Anomaluromorpha. Castorimorpha. Hystricomorpha (inc. Caviomorpha)Myomorpha. Sciuromorpha. Combined range of all rodent species (not including introduced populations)Rodents (from Latinrodere, . About 4. 0% of all mammal species are rodents; they are found in vast numbers on all continents except Antarctica. They are the most diversified mammalian order and live in a variety of terrestrial habitats, including human- made environments. Species can be arboreal, fossorial (burrowing), or semiaquatic. Well- known rodents include mice, rats, squirrels, prairie dogs, porcupines, beavers, guinea pigs, hamsters, gerbils and capybaras. Other animals such as rabbits, hares, and pikas, whose incisors also grow continually, were once included with them, but are now considered to be in a separate order, the Lagomorpha. Nonetheless, Rodentia and Lagomorpha are sister groups, sharing a most recent common ancestor and forming the clade of Glires. Most rodents are small animals with robust bodies, short limbs, and long tails. They use their sharp incisors to gnaw food, excavate burrows, and defend themselves. Most eat seeds or other plant material, but some have more varied diets. They tend to be social animals and many species live in societies with complex ways of communicating with each other. Mating among rodents can vary from monogamy, to polygyny, to promiscuity. Many have litters of underdeveloped, altricial young, while others are precocial (relatively well developed) at birth. The rodent fossil record dates back to the Paleocene on the supercontinent of Laurasia. Rodents greatly diversified in the Eocene, as they spread across continents, sometimes even crossing oceans.
Rodents reached both South America and Madagascar from Africa, and were the only terrestrial placental mammals to reach and colonize Australia. Rodents have been used as food, for clothing, as pets, and as laboratory animals in research. Some species, in particular the brown rat, the black rat, and the house mouse, are serious pests, eating and spoiling food stored by humans, and spreading diseases. Accidentally introduced species of rodents are often considered to be invasive, and have caused the extinction of numerous species, such as island birds, previously isolated from land- based predators. Characteristics. The act of chewing wears down the dentine, leaving a sharp, chisel- like edge. Top incisor outlined in yellow. Molars circled in blue. The distinguishing feature of the rodents is their pairs of continuously growing, razor- sharp incisors. As the incisors grind against each other, the softer dentine on the rear of the teeth wears away, leaving the sharp enamel edge shaped like the blade of a chisel. A gap, or diastema, occurs between the incisors and the cheek teeth in most species. This allows rodents to suck in their cheeks or lips to shield their mouth and throat from wood shavings and other inedible material, discarding this waste from the sides of their mouths. The lower jaw is thrust forward while gnawing and is pulled backwards during chewing. The Sciuromorpha, such as the eastern grey squirrel, have a large deep masseter, making them efficient at biting with the incisors. The Myomorpha, such as the brown rat, have enlarged temporalis muscles, making them able to chew powerfully with their molars. The Hystricomorpha, such as the guinea pig, have larger superficial masseter muscles and smaller deep masseter muscles than rats or squirrels, possibly making them less efficient at biting with the incisors, but their enlarged internal pterygoid muscles may allow them to move the jaw further sideways when chewing. This image shows the extended view of the incisor that is normally hidden within the dentary. While the largest species, the capybara, can weigh as much as 6. The smallest rodent is the Baluchistan pygmy jerboa, which averages only 4. Rodents have wide- ranging morphologies, but typically have squat bodies and short limbs. The elbow gives the fore arms great flexibility. The nails of burrowing species tend to be long and strong, while arboreal rodents have shorter, sharper nails. The majority of rodents have tails, which can be of many shapes and sizes. Some tails are prehensile, as in the Eurasian harvest mouse, and the fur on the tails can vary from bushy to completely bald. The tail is sometimes used for communication, as when beavers slap their tails on the water surface or house mice rattle their tails to indicate alarm. Some species have vestigial tails or no tails at all. Nocturnal species often have enlarged eyes and some are sensitive to ultraviolet light. Many species have long, sensitive whiskers or vibrissae for touch or . Some rodents have cheek pouches, which may be lined with fur. These can be turned inside out for cleaning. In many species, the tongue cannot reach past the incisors. Rodents have efficient digestive systems, absorbing nearly 8. When eating cellulose, the food is softened in the stomach and passed to the cecum, where bacteria reduce it to its carbohydrate elements. The rodent then practices coprophagy, eating its own fecal pellets, so the nutrients can be absorbed by the gut. Rodents therefore often produce a hard and dry fecal pellet. In some rodents, males are larger than females, while in others the reverse is true. Male- bias sexual dimorphism is typical for ground squirrels, kangaroo rats, solitary mole rats, and pocket gophers; it likely developed due to sexual selection and greater male- male combat. Female- bias sexual dimorphism exists among chipmunks and jumping mice. It is not understood why this pattern occurs, but in the case of yellow- pine chipmunks, males may have selected larger females due to their greater reproductive success. In some species, such as voles, sexual dimorphism can vary from population to population. In bank voles, females are typically larger than males, but male- bias sexual dimorphism occurs in alpine populations, possibly because of the lack of predators and greater competition between males. Characteristics of several rodents are given in the table below. They are the only terrestrial placental mammals to have colonized Australia and New Guinea without human intervention. Humans have also allowed the animals to spread to many remote oceanic islands (e. Polynesian rat). Others dwell on the surface of the ground, but may have a burrow into which they can retreat. Beavers and muskrats are known for being semiaquatic. In the Great Plains of North America, the burrowing activities of prairie dogs play important roles in soil aeration and nutrient redistribution, raising the organic content of the soil and increasing the absorption of water. They maintain these grassland habitats. As such, these rodents may play a role in maintaining healthy forests. When building their dams and lodges, beavers alter the paths of streams and rivers. One study found that engineering by beavers leads to a 3. Some are omnivorous and a few are predators. It occasionally eats invertebrates such as insect larvae. It also practices coprophagy. It then returns to its burrow to sort through the material it has gathered and eats the nutritious items. Too many seeds are inside to be consumed in one meal, so the agouti carries some off and caches them. This helps dispersal of the seeds as any that the agouti fails to retrieve are distant from the parent tree when they germinate. Other nut- bearing trees tend to bear a glut of fruits in the autumn. These are too numerous to be eaten in one meal and squirrels gather and store the surplus in crevices and hollow trees. In desert regions, seeds are often available only for short periods. The kangaroo rat collects all it can find and stores them in larder chambers in its burrow. Marmots do this, and may be 5. They rely on their fat reserves during their long winter hibernation. They store food for winter use by felling small trees and leafy branches in the autumn and immersing them in their pond, sticking the ends into the mud to anchor them. Here, they can access their food supply underwater even when their pond is frozen over. A functional- morphological study of the rodent tooth system supports the idea that primitive rodents were omnivores rather than herbivores. Studies of the literature show that numerous members of the Sciuromorpha and Myomorpha, and a few members of the Hystricomorpha, have either included animal matter in their diets or been prepared to eat such food when offered it in captivity. Examination of the stomach contents of the North American white- footed mouse, normally considered to be herbivorous, showed 3. It has a chunky body with short legs and tail, but is agile and can easily overpower prey as large as itself. Adult dormice may have overlapping feeding ranges, but they live in individual nests and feed separately, coming together briefly in the breeding season to mate. The pocket gopher is also a solitary animal outside the breeding season, each individual digging a complex tunnel system and maintaining a territory. Beavers live in extended family units typically with a pair of adults, this year's kits, the previous year's offspring, and sometimes older young. At high population densities, this system breaks down and males show a hierarchical system of dominance with overlapping ranges. Female offspring remain in the colony while male young disperse. Outside the breeding season, prairie voles live in close proximity with others in small colonies. A male is not aggressive towards other males until he has mated, after which time he defends a territory, a female, and a nest against other males.
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