Pygmy hippopotamus population that freely breeds in zoos around the world. Between 1970 and 1991 the population of pygmy hippos born in captivity more than doubled. The survival of the species in zoos is more certain than the survival of the species in the wild. In captivity, the pygmy hippo lives from 42 to 55 years, longer than in the wild. Since 1919, only 41 percent of pygmy hippos born in zoos have been male. While the common hippopotamus was known to Europeans since classical antiquity, the pygmy hippopotamus was unknown outside its range in West Africa until the 19th century. Due
African pygmy mouse African pygmy mouse The African pygmy mouse ("Mus minutoides") is one of the smallest rodents. It is widespread within sub-Saharan Africa, and is kept as a pet in other parts of the world. Like the common house mouse, it is a member of the enormous superfamily Muroidea, which includes about 1000 different species. Grey to brick-red overall, it is pale on the underside and has small but prominent triangular ears. Adults are between long, with a tail, and weigh from . African pygmy mice reach breeding age at about 6 to 8 weeks. Pregnancy lasts for around 20 days and