Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body. They are sometimes known as meadow mice or field mice in North Australia. Vole species form the subfamily Arvicolinae with the muskrats. There are 155 different vole species. Voles are small rodents that grow depending on the species. Females can have five to ten litters per year. Gestation lasts for the young voles reach sexual maturity in a month; as a result of this biological exponential growth, vole populations can grow large within a short time. A mating pair can birth a hundred more voles in a year. Voles outwardly resemble several other small animals. Moles, mice and shrews have similar characteristics and behavioral tendencies. Voles thrive on small plants yet, like shrews, they will eat dead animals and, like mice or rats, they can live on any nut or fruit. In addition, voles target plants more than most other small animals. Voles girdle small trees and ground cover much like a porcupine; this girdling can kill young plants and is not healthy for trees or other shrubs.
Voles eat succulent root systems and burrow under plants or ground cover and eat away until the plant is dead. Bulbs in the ground are another favorite target for voles; the presence of large numbers of voles is only identifiable after they have destroyed a number of plants. However, like other burrowing rodents, they play beneficial roles, including dispersing nutrients throughout the upper soil layers. Many predators eat voles, including martens, hawks, coyotes, foxes, snakes and lynxes. Vole bones are found in the pellets of the short-eared owl, the northern spotted owl, the saw-whet owl, the barn owl, the great gray owl, the northern pygmy owl; the average life of the smaller vole species is three to six months. These voles live longer than 12 months. Larger species, such as the European water vole, live longer and die during their second, or their third, winter; as many as 88% of voles are estimated to die within the first month of life. The prairie vole is a notable animal model for its monogamous social fidelity, since the male is socially faithful to the female, shares in the raising of pups.
The woodland vole is usually monogamous. Another species from the same genus, the meadow vole, has promiscuously mating males, scientists have changed adult male meadow voles' behavior to resemble that of prairie voles in experiments in which a single gene was introduced into the brain by a virus; the behavior is influenced by the number of repetitions of a particular string of microsatellite DNA. Male prairie voles with the longest DNA strings spend more time with their mates and pups than male prairie voles with shorter strings. However, other scientists have disputed the gene's relationship to monogamy, cast doubt on whether the human version plays an analogous role. Physiologically, pair-bonding behavior has been shown to be connected to vasopressin and oxytocin levels, with the genetic influence arising via the number of receptors for these substances in the brain. Voles have a number of unusual chromosomal traits. Species have been found with 17 to 64 chromosomes. In some species and females have different chromosome numbers, a trait unusual in mammals, though it is seen in other organisms.
Additionally, genetic material found on the Y chromosome has been found in both males and females in at least one species. In another species, the X chromosome contains 20% of the genome. All of these variations result in little physical aberration. Voles may be either monogamous or polygamous, which leads to differing patterns of mate choice and parental care. Environmental conditions play a large part in dictating which system is active in a given population. Voles live in colonies due to the young remaining in the family group for long periods. In the genus Microtus, monogamy is preferred when resources are spatially homogenous and population densities are low and where the opposite of both conditions are realized polygamous tendencies arise. Vole mating systems are sensitive to the operational sex ratio and tend toward monogamy when males and females are present in equal numbers. Where one sex is more numerous than the other, polygamy is more likely; however the most marked effect on mating system is population density and these effects can take place both inter and intra-specificallyMale voles are territorial and tend to include territories of several female voles when possible.
Under these conditions polyandry exists and males offer little parental care. Males mark and aggressively defend their territories since females prefer males with the most recent marking in a given area. Voles prefer familiar mates through olfactory sensory exploitation. Monogamous voles prefer males who have yet to mate. Mate preference in voles develops through cohabitation in as little as 24 hours; this drives young male voles to show non-limiting preference toward female siblings. This is not inclusive to females' preference for males which may help to explain the absence of interbreeding indicators. Altho
Marlborough was a parliamentary borough in Wiltshire, which elected two Members of Parliament to the House of Commons from 1295 until 1868, one member from 1868 until 1885, when the borough was abolished. Notes Baring was appointed a Lord Commissioner of the Treasury and Bruce was appointed Vice-Chamberlain of the Household, requiring by-elections. Brudenell-Bruce was appointed Vice-Chamberlain of the Household. Seat reduced to one member Brudenell-Bruce succeeded to the peerage. Bruce was appointed Vice-Chamberlain of the Household. References SourcesRobert Beatson, A Chronological Register of Both Houses of Parliament D Brunton & D H Pennington, Members of the Long Parliament Cobbett's Parliamentary history of England, from the Norman Conquest in 1066 to the year 1803 F W S Craig, British Parliamentary Election Results 1832-1885 J Holladay Philbin, Parliamentary Representation 1832 - England and Wales Leigh Rayment's Historical List of MPs – Constituencies beginning with "M"
The Bahia gubernatorial election, 2010 will be held on October 3, as part of the general elections in Brazil. In this election, Bahian citizens eligible to vote will decide if incumbent Governor Jaques Wagner, of the center-left Workers' Party, should receive a new four-year term, his main challengers are former Governor Paulo Souto, of the right wing Democrats, Minister for National Integration Geddel Vieira Lima, of centrist Brazilian Democratic Movement Party. If none of the candidates achieve more than a half of the valid votes, a run-off will be held on October 31, 2010. Scenario 2010 First scenario Second scenario Third scenario Fourth scenario