House mice originated in Asia but have since spread throughout the world. Along with brown rats, they are considered to be the most widespread terrestrial mammal other than humans.

Life span
Up to two years.

Statistics
Body length: 6.5-10cm, Weight: 12-22g.

Physical description
House mice have brown-grey fur, with slightly lighter under-parts. They have large ears, a pointed snout and a long tail.

Distribution
Although they are thought to be native to Asia, house mice now have an almost worldwide distribution.

Habitat
They are typically found in areas near to human habitation and open fields.

Diet
They feed on practically everything, but prefer to eat cereals and insects.

Behaviour
House mice are nocturnal. Wild populations are poor competitors with other rodents, and are often displaced by other species when away from human habituation.

They are typically aggressive to each other, and fighting is common, although females have an aggression inhibiting hormone in their urine to prevent attack from other mice.

House mice build tunnel systems which may be a short tunnel with just one chamber or a complex network with several exits and chambers. Some of these chambers may contain bedding material.

Reproduction
Females produce about 5-10 litters per year, consisting of 4-8 young. The young are independent after 3 weeks.

Conservation status
House mice are common. They are considered to be a major pest as they spoil a large amount of stored food and are a carrier of several diseases.