Mongolian gerbil

The Mongolian gerbil, also called the Mongolian jird, Meriones unguiculatus, is a rodent of the subfamily Gerbillinae with a body length of 110 to 135 millimetres, a tail of 95 to 120 millimetres and a weight of 60 to 130 grams, males being larger than females. In the wild it inhabits grassland, shrubland and desert, including semidesert and steppe, in China, Mongolia and Russia. It lives in patriarchal groups, usually a parental pair with their latest litter and a few older pups, around a central burrow with 10 to 20 exits, and it eats the seeds of grasses, leaves, bulbs and herbs. Father Armand David sent specimens from northern China to Paris in 1866 and Alphonse Milne-Edwards named the species in 1867. It entered scientific research in the later nineteenth century and became a popular pet in the English-speaking world after 1954, although its use in research has since declined.