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African Pygmy Mouse
The African pygmy mouse (''Mus minutoides'') is one of the smallest rodents. It is widespread within sub-Saharan Africa, and is kept as a pet in other parts of the world. Like the common house mouse, it is a member of the enormous superfamily Muroidea, which includes about 1000 different species. Grey to brick-red overall, it is pale on the underside and has small but prominent triangular ears. Adults are between long, with a tail, and weigh from . African pygmy mice reach breeding age at about 6 to 8 weeks. Pregnancy lasts for around 20 days and the litter of about three young is born blind and hairless. Their eyes open after 2 weeks, and weaning is complete after 4 weeks. The lifespan is about 2 years, although individual specimens have been reported to live over 4 years in captivity. The African pygmy mouse has a number of unique traits. It stacks pebbles in front of its burrow. Overnight, the pebbles gather dew and in the morning, the pygmy mouse drinks the dew on the pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andrew Smith (zoologist)
Sir Andrew Smith (3 December 1797 – 11 August 1872) was a British surgeon, explorer, ethnologist and zoologist. He is considered the father of zoology in South Africa having described many species across a wide range of groups in his major work, ''Illustrations of the Zoology of South Africa''. Smith was born in Hawick, Roxburghshire. He qualified in medicine at the University of Edinburgh obtaining an M.D. degree in 1819, having joined the Army Medical Services in 1816. South Africa 1820–1837 In 1820 he was ordered to the Cape Colony and was sent to Grahamstown to supervise the medical care of European soldiers and soldiers of the Cape Corps. He was appointed the Albany district surgeon in 1822 and started the first free dispensary for indigent patients in South Africa. He led a scientific expedition into the interior and was able to indulge in his interests of natural history and anthropology. On several occasions, he was sent by governors on confidential missions to vis ... [...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] |
House Mouse
The house mouse (''Mus musculus'') is a small mammal of the order Rodentia, characteristically having a pointed snout, large rounded ears, and a long and almost hairless tail. It is one of the most abundant species of the genus '' Mus''. Although a wild animal, the house mouse has benefited significantly from associating with human habitation to the point that truly wild populations are significantly less common than the semi-tame populations near human activity. The house mouse has been domesticated as the pet or fancy mouse, and as the laboratory mouse, which is one of the most important model organisms in biology and medicine. The complete mouse reference genome was sequenced in 2002. Characteristics House mice have an adult body length (nose to base of tail) of and a tail length of . The weight is typically . In the wild they vary in color from grey and light brown to black (individual hairs are actually agouti coloured), but domesticated fancy mice and laboratory mice ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superfamily (zoology)
In biological classification, taxonomic rank is the relative level of a group of organisms (a taxon) in an ancestral or hereditary hierarchy. A common system consists of species, genus, family, order, class, phylum, kingdom, domain. While older approaches to taxonomic classification were phenomenological, forming groups on the basis of similarities in appearance, organic structure and behaviour, methods based on genetic analysis have opened the road to cladistics. A given rank subsumes under it less general categories, that is, more specific descriptions of life forms. Above it, each rank is classified within more general categories of organisms and groups of organisms related to each other through inheritance of traits or features from common ancestors. The rank of any ''species'' and the description of its ''genus'' is ''basic''; which means that to identify a particular organism, it is usually not necessary to specify ranks other than these first two. Consider a particular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muroidea
The Muroidea are a large superfamily of rodents, including mice, rats, voles, hamsters, lemmings, gerbils, and many other relatives. Although the Muroidea originated in Eurasia, they occupy a vast variety of habitats on every continent except Antarctica. Some authorities have placed all members of this group into a single family, Muridae, due to difficulties in determining how the subfamilies are related to one another. Many of the families within the Muroidea superfamily have more variations between the families than between the different clades. A possible explanation for the variations in rodents is because of the location of these rodents; these changes could have been due to radiation or the overall environment they migrated to or originated in. The following taxonomy is based on recent well-supported molecular phylogenies. The muroids are classified in six families, 19 subfamilies, around 280 genera, and at least 1,750 species. Taxonomy *Family Platacanthomyidae (spiny ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sex-determination System
A sex-determination system is a biological system that determines the development of sexual characteristics in an organism. Most organisms that create their offspring using sexual reproduction have two sexes. In some species there are hermaphrodites. There are also some species that are only one sex due to parthenogenesis, the act of a female reproducing without fertilization. In some species, sex determination is genetic: males and females have different alleles or even different genes that specify their sexual morphology. In animals this is often accompanied by chromosomal differences, generally through combinations of XY, ZW, XO, ZO chromosomes, or haplodiploidy. The sexual differentiation is generally triggered by a main gene (a "sex locus"), with a multitude of other genes following in a domino effect. In other cases, sex of a fetus is determined by environmental variables (such as temperature). The details of some sex-determination systems are not yet fully underst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X Chromosome
The X chromosome is one of the two sex-determining chromosomes (allosomes) in many organisms, including mammals (the other is the Y chromosome), and is found in both males and females. It is a part of the XY sex-determination system and XO sex-determination system. The X chromosome was named for its unique properties by early researchers, which resulted in the naming of its counterpart Y chromosome, for the next letter in the alphabet, following its subsequent discovery. Discovery It was first noted that the X chromosome was special in 1890 by Hermann Henking in Leipzig. Henking was studying the testicles of ''Pyrrhocoris'' and noticed that one chromosome did not take part in meiosis. Chromosomes are so named because of their ability to take up staining (''chroma'' in Greek means ''color''). Although the X chromosome could be stained just as well as the others, Henking was unsure whether it was a different class of object and consequently named it ''X element'', which later be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammals Described In 1834
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or hair, and three middle ear bones. These characteristics distinguish them from reptiles (including birds) from which they diverged in the Carboniferous, over 300 million years ago. Around 6,400 extant species of mammals have been described divided into 29 orders. The largest orders, in terms of number of species, are the rodents, bats, and Eulipotyphla (hedgehogs, moles, shrews, and others). The next three are the Primates (including humans, apes, monkeys, and others), the Artiodactyla ( cetaceans and even-toed ungulates), and the Carnivora (cats, dogs, seals, and others). In terms of cladistics, which reflects evolutionary history, mammals are the only living members of the Synapsida (synapsids); this clade, together w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mus (rodent)
Mus or MUS may refer to: Abbreviations * MUS, the NATO country code for Mauritius * MUS, the IATA airport code for Minami Torishima Airport * MUS, abbreviation for the Centre for Modern Urban Studies on Campus The Hague, Leiden University, Netherlands * MUS, abbreviation for Medically unexplained physical symptoms * MUS, abbreviation for the Memphis University School * MUS, abbreviation for the Movimiento Unión Soberanista * MUS, abbreviation for Multiple-use water supply system, a low-cost, equitable water supply systems * Mus, abbreviation for Musca, a southern constellation * mus, ISO-639 code for the Muscogee language * Mus., abbreviation used in music degrees such as B.Mus. and M.Mus. * MUs, or million units of energy, used in India for a gigawatt hour People * Anders Mus (fl. 1501–1535), Danish civil servant in Norway * Conny Mus (1950–2010), Dutch journalist, best known as a correspondent for ''RTL Nieuws'' in Israel and the Middle East * Gus Mus (born 1944), I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodents Of Africa
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 incisors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
