The multimammate mice (also called multimammate rats, African soft-furred rats or natal-rats) are found in most parts of Sub-Saharan Africa. Their head-body length is between 10 and 17 cm, their tail length is between 8 and 15 cm and their weight varies between 20 and 80 grams, depending on the species. Domesticated Multimammate mice are heavier on average, weighting as much as 100 Grams. They are omnivorous and live up to four years. A female can have as many as 12 litters a year.
Systematically they were long placed in the genus Rattus (referred to as Rattus natalensis). Later they were placed in the genus Mus (referred to as Mus natalensis) and then they were placed in the genus Praomys. Today molecular research has discovered that they are a genus of their own (Mastomys) and that they are closely related to Praomys. They are more closely related to Mus than to Rattus. All the domesticated multimammate mice are hybrids between the natal multimammate mouse (Mastomys natalensis) and the Southern multimammate mouse (Mastomys coucha).