Muridae

The Muridae are the largest family of mammals, containing over 700 species found naturally throughout Eurasia, Africa, and Australia. They have been introduced worldwide. The group includes true mice and rats, gerbils, and relatives.

The family name Muridae is sometimes used in a broader sense to include all members of the superfamily Muroidea. The name comes from the Latin mus (genitive muris), meaning "mouse".

Characteristics
The murids are small mammals, typically around 10 cm long excluding the tail, but ranging from 4.5 to 8 cm in the African pygmy mouse to 48 cm in Cuming's slender-tailed cloud rat. They typically have slender bodies with scaled tails, and pointed snouts with prominent whiskers, but with wide variation in these broad traits. Many murids have elongated legs and feet to allow them to move with a hopping motion, while others have broad feet and prehensile tails to improve their climbing ability, and yet others have neither adaptation. They are most commonly some shade of brown in colour, although many have black, grey, or white markings.

Murids generally have excellent senses of hearing and smell. They live in a wide range of habitats from forest to grassland, and mountain ranges. A number of species, especially the gerbils, are adapted to desert conditions, and can survive for a long time with minimal water. They are either herbivores or omnivores, eating a wide range of foods in different species, with the aid of powerful jaw muscles and gnawing incisors that grow throughout life. The dental formula of murids is.

Murids breed frequently, often producing large litters several times per year. They typically give birth between 20 and 40 days after mating, although this varies greatly between species. The young are typically born blind, hairless, and helpless, although there are exceptions, such as the spiny mice.

Evolution
As with many other small mammals, the evolution of the murids is not well known, as few fossils survive. They probably evolved from hamster-like animals in tropical Asia some time in the early Miocene, and to have only subsequently produced species capable of surviving in cooler climes. They have become especially common worldwide during the Holocene, as a result of hitching a ride with human migrations.

Classification
The murids are classified in five subfamilies, around 150 genera and approximately 710 species.

Subfamilies

 * Deomyinae (spiny mice, brush furred mice, link rat)
 * Gerbillinae (gerbils, jirds and sand rats)
 * Leimacomyinae (Togo mouse)
 * Lophiomyinae (Maned rat or crested rat)
 * Murinae (Old World rats and mice, including the vlei rats)