Mouse

? Mouse Fossil range: Late Miocene - Recent
House mouse, Mus musculus
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Rodentia Superfamily: Muroidea Family: Muridae Subfamily: Murinae Genus: Mus Linnaeus, 1758

The mouse is a mammal that belongs to one of numerous species of small rodents in the genus Mus and various related genera of the family Muridæ (Old World Mice).

The best known mouse species is the common house mouse (Mus musculus). It is found in nearly all countries and, as the laboratory mouse, serves as an important model organism in biology; it is also a popular pet. (Non-biologists often use the term "mouse" synonymously with "Mus musculus"). The American white-footed mouse (Peromyscus leucopus) and the deer mouse ( Peromyscus maniculatus) also sometimes live in houses. These species of mice live commensally with humans. Although they may live up to two years in the lab, the average mouse in the wild lives only 3 months, primarily due to heavy predation. Cats, wild dogs, birds-of-prey, and snakes prey heavily upon mice.

Mice can be harmful pests, damaging and eating crops and spreading diseases through their parasites and feces. The original motivation for the domestication of cats is thought to have been for their predation of mice and their relatives, the rats. A mouse trap can also be used to catch mice.

Mice cannot see colors, but they can see shades from black to white.

There are 38 species in the genus Mus.

Diet

Mice generally live on a herbivore diet, but are actually omnivores: they will eat meat, the dead bodies of other mice, and have been observed to self-cannibalise their tails during starvation. Mice eat grains and fruits for a regular diet. (Which is the main reason they damage crops.)

Mice in laboratory experiments

Mice are very common experimental animals in biology and psychology primarily because they are mammals, and thus share a high degree of homology with humans, but can be manipulated in ways that would be considered unethical to do with humans.

Usually genetically uniform strains of mice are used in experiments. Mice can be deleted for specific genes to study the function of the gene in question. Mice which have deletions of both copies of the same gene are called knock outs for that gene. The so called nude mice is a strain bearing a spontaneous mutation. Nude mice have no hair and they are also called SCID mice, for Severe Combined Immunodeficiency, as their immunesystem is impaired. Nude mice can be used in cancer studies, they do not reject cells and tissue from other mice or even other species which can be tested in the mouse for tumorforming capacities.

Additional benefits of mice in laboratory research include the fact that mice are small, relatively inexpensive, and several generations can be observed in a short period of time. The mouse genome has been sequenced, and many genes which share homology to human genes have been identified. In the 2006 Biosatellite project, a group of mice will orbit Earth inside a spinning spacecraft to determine how mice react to gravity equivalent to that of Mars. [1]

Mice as pets

Mice are now one of the leading rodent pets. Although their main purpose in pet stores is to be sold as snake food, many people buy mice as companion pets. Some common products used are:

• Cage- Usually a hamster or gerbil cage, but special mouse cages are now available
• Food- Special pelleted and seed-based food is available.
• Bedding- Usually hardwoods, such as aspen. Cedar or pine should not be used because it contains harmful oils that can damage any rodent's respiratory system. A fairly new product in the market is recycled virgin wood pulp, an environmentally-friendly, safe, clean, and efficient product. The most popular is Carefresh bedding. Another excellent litter available is chopped-up dried corn cobs.

Some benefits of having mice as pets are

• Minimal shedding and allergens
• Entertaining and affectionate
• Inexpensive
• Clean (contrary to popular belief)
• Socially self-sufficient (when in a group of other mice)

There are, however, some disadvantages to having pet mice

• Small and quite fragile (not as easy to handle as a dog or a cat)
• Nocturnal
• Frequent eye infections under stress
• Easily subject to disease when without optimal care
• Frequent reproduction
• Short lifespan
• The male's urine gives off an unpleasant odor

Taxonomy of the genus Mus

• Genus Mus
  • Subgenus Pyromys
    • Mus platythrix
    • Mus saxicola
    • Mus philipsi
    • Mus shortridgei
    • Mus fernandoni
  • Subgenus Coelomys
    • Mus mayori
    • Mus pahari
    • Mus crociduroides
    • Mus vulcani
    • Mus famulus
  • Subgenus Mus
    • Mus caroli
    • Mus cervicolor
    • Mus cookii
    • Mus booduga
    • Mus terricolor
    • Mus musculus
    • Mus spretus
    • Mus macedonicus
    • Mus spicelegus
    • Mus fragilicauda
  • Subgenus Nannomys
    • Mus callewaerti
    • Mus setulosus
    • Mus triton
    • Mus bufo
    • Mus tenellus
    • Mus haussa
    • Mus mattheyi
    • Mus indutus
    • Mus setzeri
    • Mus musculoides
    • Mus minutoides
    • Mus orangiae
    • Mus mahomet
    • Mus sorella
    • Mus kasaicus
    • Mus neavei
    • Mus oubanguii
    • Mus goundae
    • Mus baoulei

Trivia

An estimated half million mice live on the London Underground, mostly running around the tracks.