Cute as a button and teeny-weeny at 5 to 7 cm including the tail, the indigenous African Pygmy Mouse (Mus minutoides) is a close relative of the common house mouse. The bodies of these mice are typically 2 to 2,5 cm with the females usually a little larger than the boys.
Predominantly nocturnal but occasionally diurnal too, these very social critters are extremely active, consuming vast amounts of water relative to their size. Habitats are savannah, grassland, rocks and suburban areas, while their diet consists of insects, seeds and fruit.
They’re prolific breeders with a gestation period of 20 days and litters of one to six. At seven days the young begin growing hair, at 12 days they open their eyes and at about 17 days they start exploring outside the nest. They reach sexual maturity at four to six weeks of age and live between one to three years.
Contrary to most mammals, the majority of the females carry an XY chromosome pair, rather than XX. Moreover, there are still female African pygmy mice that carry XX chromosomes. Studies indicate that the X chromosome of XY females is different to the X chromosome in the XX females and XY males. It’s believed that the X chromosome of XY females contains an unknown mutation which prevents them from developing as males.
Ref: thewebsiteofeverything; earlham.ac.uk