Mice Rats and Relatives: Muridae

Rats, mice, and relatives are found throughout the world except for the extreme polar regions of Earth.

Rats, mice, and relatives live in many different habitats including open flatlands, savannas (flat grasslands), grasslands, prairies, steppes (treeless plains that are often somewhat dry and grass-covered), woodlands, forests, deserts, scrublands, foothills, jungles, rainforests, wetlands, cultivated lands and fields, and along waterways and water bodies. They are found from dry temperate (mild) climates to wet tropical environments.

Most species of rats, mice, and relatives eat at least a few of the following foods: grasses, seeds, grains, root vegetables such as bulbs and tubers, green plant parts, conifer needles, nuts, berries, fruits, insects and insect larvae (LAR-vee), fish, lizards, frogs, baby birds, crabs, tadpoles, salamanders, fungus, lichens, mosses, other small vertebrates (animals with a backbone) and invertebrates (animals without a backbone), and carrion (decaying animals).

Rats, mice, and relatives are generally considered pests in agricultural and forested lands. Large species are often trapped for their fur. Some species carry diseases that can sicken and kill people. Rats, mice, and relatives are frequently used as laboratory research animals. Some, such as hamsters and gerbils, are kept as pets. They are often important in maintaining a healthy ecosystem in their natural habitats.

Almost 450 species of murids are listed on the World Conservation Union's (IUCN) Red List. Of these, twenty-one are Extinct, died out; fifty are Critically Endangered, facing an extremely high risk of extinction in the wild; seventy-four are Endangered, facing a very high risk of extinction in the wild; and 110 are Vulnerable, facing a high risk of extinction in the wild.