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mouse,name applied to numerous species of small rodentsrodent,
member of the mammalian order Rodentia, characterized by front teeth adapted for gnawing and cheek teeth adapted for chewing. The Rodentia is by far the largest mammalian order; nearly half of all mammal species are rodents.
..... Click the link for more information. , often having soft gray or brown fur, long hairless tails, and large ears. The chief distinction between these animals and the variety of rodents called ratsrat,
name applied to various stout-bodied rodents, usually having a pointed muzzle, long slender tail, and dexterous forepaws. It refers particularly to the two species of house rat, Rattus norvegicus, the brown, or Norway, rat and R.
..... Click the link for more information. is in size: mice are usually smaller. Many small rodents are adapted for leaping or hopping and are named accordingly, e.g., the North American kangaroo rat and Asian jumping mouse.
Types of Mice
Most, but not all, of the rodents called mice are members of the rodent subclass Myomorpha, or mouselike rodents. The approximately 1,100 species in this enormous group are classified in several families. The Old World family Muridae includes the now ubiquitous house mouse, as well as a great variety of wild-living Old World species, including the Old World field mouse, the tiny European harvest mouse (Micromys minutus) and the African tree mice. The cosmopolitan family Cricetidae includes the native New World mice, such as the deer mouse, American harvest mouse (Reithrodontomys), the carnivorous grasshopper mouse, the South American field mice, the pack rat, and the rice rat; it also includes the various Old and New World species of volevole,
name for a large number of mouselike rodents, related to the lemmings. Most range in length from 3 1-2 to 7 in. (9–18 cm) and have rounded bodies with gray or brown coats, blunt muzzles, small ears concealed in the long fur, and short tails.
..... Click the link for more information. , hamsterhamster,
Old World rodent, related to the voles, lemmings, and New World mice. There are many hamster species, classified in several genera. All are solitary, burrowing, nocturnal animals, with chunky bodies, short tails, soft, thick fur, and large external cheek pouches used
..... Click the link for more information. , lemminglemming,
name for several species of mouselike rodents related to the voles. All live in arctic or northern regions, inhabiting tundra or open meadows. They frequently nest in underground burrows, particularly in winter, although they do not hibernate.
..... Click the link for more information. , muskratmuskrat,
North American aquatic rodent. The common muskrats, species of the genus Ondatra, are sometimes called by their Native American name, musquash. They are found in marshes, quiet streams, and ponds through most of North America N of Mexico, but are absent from the
..... Click the link for more information. , and gerbilgerbil
, small desert rodent found throughout the hot arid regions of Africa and Asia. Also known as sand rats, gerbils have large eyes and powerful, elongated hind limbs upon which they can spring. Gerbils are 3 to 5 in. (7.6–12.
..... Click the link for more information. . Still other families of the Myomorpha include the dormousedormouse,
name for Old World nocturnal rodents of the family Gliridae. There are many dormouse species, classified in several genera. Many resemble small squirrels. Dormice sleep deeply during the day, and European species hibernate for nearly six months of the year; their name
..... Click the link for more information. , jumping mousejumping mouse,
rodent slightly larger than the common mouse, found in North America and N Asia, also called the kangaroo mouse. Its long hind legs and tail enable it to leap distances up to 12 ft (3.7 m). Jumping mice have gray to brown fur and are white underneath.
..... Click the link for more information. , and jerboajerboa
, name for the small, jumping rodents of the family Dipodidae, found in arid parts of Asia, N Africa, and SE Europe. Jerboas have extremely long hind feet and short forelegs; they always walk upright or hop like kangaroos.
..... Click the link for more information. . The pocket mousepocket mouse,
small jumping rodent of W North America and as far south as N South America. More closely related to the squirrel than the true mouse, the pocket mouse gets its name from the fur-lined cheek pouches in which it carries its food. It varies in length from 3 to 12 in.
..... Click the link for more information. and the kangaroo ratskangaroo rat,
small, jumping desert rodent, genus Dipodomys, related to the pocket mouse. There are about 20 kangaroo rat species, found throughout the arid regions of Mexico and the S and W United States.
..... Click the link for more information. and mice are members of the suborder Sciuromorpha, or squirrellike rodents.
The house mouse, Mus musculus, found throughout the world, is the most familiar of the mice; many of its races live commensally with humans and are serious pests, while others live in the wild. It usually measures about 6 in. (15 cm) long and weighs under 1 oz (28 grams). It has gray to brown fur, large rounded ears, a pointed muzzle, and a naked scaley tail. An omnivorous feeder, it causes great destruction and contamination of food supplies. Its nests are built of available chewable materials, such as clothing and paper. It may carry human diseases, such as typhoid and spotted fever. Females produce litters of four to eight young after a gestation period of three weeks; under favorable conditions they breed throughout the year. The young mature in two months. House mice, particularly albino strains, are extensively used in biological and medical experimentation and are also sometimes kept as pets.
Field mouse is a name applied to various wild-living mice in different parts of the world. The Old World field mice are species of the genus Apodemus, closely related to the house mouse and found throughout Eurasia and North Africa. The widely distributed long-tailed field mouse, Apodemus sylvaticus, is a nocturnal, burrowing creature that prefers succulent plant food and frequently invades gardens and houses. In North America the name field mouse (or meadow mouse) is applied to voles. South American field mice belong to the genus Akodon, with about sixty species distributed among a wide variety of habitats, including human dwellings. Most of these resemble long-tailed voles. The name tree mouse is likewise applied to various arboreal mice and voles in different parts of the world.
Mice are classified in the phylum ChordataChordata
, phylum of animals having a notochord, or dorsal stiffening rod, as the chief internal skeletal support at some stage of their development. Most chordates are vertebrates (animals with backbones), but the phylum also includes some small marine invertebrate animals.
..... Click the link for more information. , subphylum Vertebrata, class Mammalia, order Rodentia.
What does it mean when you dream about a mouse?
A mouse in a dream can indicate much scurrying, flitting, and running about—like a scared little mouse trying to hide in a hole and not having to confront things that could get one trapped. (See also Rat, Rodent).
["Mouse, A Language for Microcomputers", P. Grogono <email@example.com> Petrocelli Books, 1983].
A conventional roller-ball mouse is slid across the surface of the desk, often on a mouse mat. As the mouse moves, a ball set in a depression on the underside of the mouse rolls accordingly. The ball is also in contact with two small shafts set at right angles to each other inside the mouse. The rotating ball turns the shafts, and sensors inside the mouse measure the shafts' rotation. The distance and direction information from the sensors is then transmitted to the computer, usually through a connecting wire - the mouse's "tail". The computer then moves the mouse pointer on the screen to follow the movements of the mouse. This may be done directly by the graphics adaptor, but where it involves the processor the task should be assigned a high priority to avoid any perceptible delay.
Some mice are contoured to fit the shape of a person's right hand, and some come in left-handed versions. Other mice are symmetrical.
Included on the mouse are usually two or three buttons that the user may press, or click, to initiate various actions such as running programs or opening files. The left-most button (the primary mouse button) is operated with the index finger to select and activate objects represented on the screen. Different operating systems and graphical user interfaces have different conventions for using the other button(s). Typical operations include calling up a context-sensitive menu, modifying the selection, or pasting text. With fewer mouse buttons these require combinations of mouse and keyboard actions. Between its left and right buttons, a mouse may also have a wheel that can be used for scrolling or other special operations defined by the software. Some systems allow the mouse button assignments to be swapped round for left-handed users.
Just moving the pointer across the screen with the mouse typically does nothing (though some CAD systems respond to patterns of mouse movement with no buttons pressed). Normally, the pointer is positioned over something on the screen (an icon or a menu item), and the user then clicks a mouse button to actually affect the screen display.
The five most common "gestures" performed with the mouse are: point (to place the pointer over an on-screen item), click (to press and release a mouse button), double-click to press and release a mouse button twice in rapid succession, right-click (to press and release the right mouse button}, and drag (to hold down the mouse button while moving the mouse).
Most modern computers include a mouse as standard equipment. However, some systems, especially portable laptop and notebook models, may have a trackball, touchpad or Trackpoint on or next to the keyboard. These input devices work like the mouse, but take less space and don't need a desk.
Many other alternatives to the conventional roller-ball mouse exist. A tailless mouse, or hamster, transmits its information with infrared impulses. A foot-controlled mouse is one used on the floor underneath the desk. An optical mouse uses a light-emitting diode and photocells instead of a rolling ball to track its position. Some optical designs may require a special mouse mat marked with a grid, others, like the Microsoft IntelliMouse Explorer, work on nearly any surface.
PC Guide's "Troubleshooting Mice".
mouseThe primary pointing device on a desktop computer. Laptops have the equivalent function in a built-in trackpad, although many users prefer the handheld mouse.
Decades ago, it was called a "mouse" because the cord resembled a mouse's tail, and wired mice plug into the USB or PS/2 port. Today, most mice are cordless, using Bluetooth (if in the computer) or by plugging the transceiver that comes with the mouse into the USB port. See USB and PS/2 port.
Although CAD and drawing programs, as well as every graphical interface, are designed to be used with a pointing device, many key commands in the OS and business applications are also available.
Relative vs. Absolute
Mouse movement is relative. For example, a mouse could be moved along your arm or across your stomach, and the screen cursor would move from its existing location the same angle and distance. In contrast, the mouse-like object on a graphics tablet, which is correctly called a "tablet cursor" or "puck," is often not relative. It contacts the tablet with absolute reference, which means if you place the stylus on the upper left part of the tablet, the screen cursor appears on the upper left side of the screen. See pointing device, scroll mouse, mechanical mouse, optical mouse, Magic Mouse and mickey.
Mice Are Not Always Friendly
It is well known that hours of clicking can strain the wrist (see carpal tunnel syndrome). In addition, there is way too much mouse movement in today's operating systems and applications on desktop computers. Instead of the next item to click presented on screen close to the last position of the pointer (cursor), the next obvious selection is often at the other end of the screen. See good user interface.
|First Public Mouse Demonstration|
|Invented by Doug Engelbart in the 1960s at Stanford Research Institute (SRI), it used two moving wheels 90 degrees apart. Subsequent mechanical mice were similar but with rubberized trackballs moving internal wheels. (Image courtesy of The Bootstrap Institute.)|
|One Size Does Not Fit All|
|Contour Design makes mice that come in many sizes for a perfect fit. They also put less strain on the "clicking finger." (Image courtesy of Contour Design, Inc., www.contourdesign.com)|
|A Variety of Critters|
|All kinds of mouse designs have come and gone over the years. (Image courtesy of Palo Alto Research Center (PARC), Brian Tramontana, Photographer.)|