"...And All Through the House Not a Creature Was Stirring Not Even a Mouse."  Wait, a Mouse in the House?!


Mouse in the Wild
        Although the species Mus musculus is found on every content in the world, except for Antarctica, it is actually not native to most parts of the world and had to be introduced from other areas.  As far as the U.S. goes, this species is thought to have been brought in around the time of the American Revolution from Europe. 
     As the common name suggests, Mouse In a Sink
this species can often times be found in the home, but this should not be thought of as its primary place of residence.  They usually enter homes during times of harvest when the ground covering in the crop fields where they usually live becomes scarce.  The are nomadic in the sense that they are often moving from one field to the next. 
    How can you tell if you share your home with Mus musculus?  This species is nocturnal and is often not seen during the day, but there are a couple of key things to look for.  Because of their continuously growing incisors, they often leave holes in the walls and other surfaces where they have been gnawing to keep their teeth short.  Also, one can often spot black, elongated droppings in cupboards, draws, and other surfaces of the home.  They often make their nests in shoes, furniture, or debris and other soft surfaces.  Urine is used to mark their territory and to inhibit aggression from other species, so often the mouse can be smelt before it is actually seen.  Mice also can be heard making various calling and squeaking noises.   
Typical Mouse Cage

     Because of their ability to reproduce rapidly (we will talk more about this in a bit) and ability to survive with very little water, Mus musculus is often used in laboratory experiments when testing for anything from genetic disease, to drug effects, to making antibodies used for clinical settings.  For this reason, this species, as well as other rodent species, are often found living in cages.