The Canadian Encyclopedia — neutral, cited, updated
July 26, 2026Sources cited
Canadianwire.
Canada’s encyclopedia & explainer
HomeScience & NatureMammalsMouse
Science & Nature • Mammals

Mouse

A mouse is a small rodent, commonly referring to species in the genus Mus, especially the house mouse (Mus musculus).

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated July 26, 2026|2 min read| Fact-checked

A mouse is a small rodent, typically referring to species in the genus Mus, particularly the house mouse (Mus musculus). The term is also applied to other small rodent species with a similar body form. Mice are known for their adaptability, high reproductive rate, and extensive use in scientific research.

Classification and naming

In scientific usage, the term mouse usually refers to species in the genus Mus, a group within the family Muridae. In everyday language, the word is also used for other small rodents with a mouse-like body form, though they may belong to different genera.

Physical characteristics

Mice are generally small rodents with a pointed snout, small rounded ears, and a long scaly tail that is about the length of the body. They are adapted for quick movement, and many species are capable of climbing, leaping, or swimming.

Habitat and behaviour

Mice occur in many regions worldwide and are often nocturnal. Many species live on the ground and construct burrows or nests of dry vegetation. They are adaptable to a wide range of habitats, including those closely associated with humans.

Relationship with humans

The house mouse (Mus musculus) has spread alongside humans across much of the world. Some mouse species are considered pests because they damage stored food and can carry disease organisms. Additionally, mice are among the most commonly used mammalian model organisms in biology and psychology research.

Key facts

  • The word mouse most commonly refers to small rodents in the genus Mus, though it is also used for similar rodents in other genera.
  • The best-known species is the house mouse (Mus musculus), which has spread widely with human populations.
  • Mice are among the most commonly used mammalian model organisms in biology and psychology research.
  • Some species are considered pests because they damage stored food and can carry disease organisms.
🍁
Canadian context

House mice and other mouse species are familiar in Canadian homes, farms, and laboratories, and mice are also a standard model organism in Canadian biomedical and psychology research.

Frequently asked questions

What is a mouse in biology?
A mouse is a small rodent, usually referring to species in the genus Mus, especially the house mouse.
What is the best-known mouse species?
The best-known species is the house mouse (Mus musculus).
Are all mouse-like rodents in the genus Mus?
No. The word mouse is used broadly for several small rodent species outside Mus as well.
Why are mice important in research?
They are widely used as mammalian model organisms because they are mammals and share many biological similarities with humans.
Are mice pests?
Some species, especially house mice, are treated as pests because they can contaminate food and damage materials.
Where do mice live?
Mice live in many habitats worldwide, including areas closely associated with humans, and many species also live in burrows or nests.

References

  1. Wikipediahttps://en.wikipedia.org/wiki/Mouse
    Supports: General definition, genus Mus, house mouse, adaptability, research use
  2. Encyclopaedia Britannicahttps://www.britannica.com/animal/mouse-rodent
    Supports: Scientific definition, genus Mus, habitat, nocturnal behaviour, classification
  3. Britannica Kidshttps://kids.britannica.com/students/article/mouse/275961
    Supports: Physical traits, diet, habitat, pest status, common house mouse facts