Батыс Африканың кішкентай суайғыры

Small species of hippopotamus from West Africa

Speciesbox
| name = Pygmy hippopotamus
| image = Hexaprotodon liberiensis in Edinburgh Zoo. JPG
| image caption = A pygmy hippopotamus at Edinburgh Zoo
| status = EN
| status system = IUCN3.1
| status ref =
| status2 = CITES A2
| status2 system = CITES
| status2 ref =
| display parents = 2
| genus = Choeropsis
| parent authority = Leidy, 1853
| species = liberiensis
| authority = (Morton, 1849) The survival of the species in captivity is more assured than in the wild; in a 2015 assessment, the International Union for Conservation of Nature estimated that fewer than 2,500 pygmy hippos remain in the wild. A male pygmy hippopotamus is known as a bull, a female as a cow, and a baby as a calf. A group of hippopotami is known as a herd or a bloat. The pygmy hippopotamus is a member of the family Hippopotamidae where it is classified as a member of the genus Choeropsis ("resembling a hog"). Members of Hippopotamidae are sometimes known as hippopotamids. Sometimes the sub family Hippopotaminae is used. Further, some taxonomists group hippopotami and anthracotheres in the superfamily Anthracotheroidea or Hippopotamoidea. The taxonomy of the genus of the pygmy hippopotamus has changed as understanding of the animal has developed. All agree that the modern pygmy hippopotamus, be it H. liberiensis or C. liberiensis, is the only extant member of its genus. The American Society of Mammalogists moved it back to Choeropsis in 2021, a move supported by the IUCN. He estimated that perhaps no more than 30 pygmy hippos remained in the region. Heslop sent four pygmy hippopotamus skulls he collected to the British Museum of Natural History in London. These specimens were not subjected to taxonomic evaluation, however, until 1969 when classified the skulls as belonging to a separate subspecies based on consistent variations in the proportions of the skulls. The Nigerian pygmy hippos were seen or shot in Rivers State, Imo State and Bayelsa State, Nigeria. While some local populations are aware that the species once existed, its history in the region is poorly documented. This hypothesized ancestor likely split into two branches about six million years later. One branch would evolve into cetaceans, the other branch became the anthracotheres, a large family of four legged beasts, whose earliest member, from the Late Eocene, would have resembled narrow hippopotami with comparatively small and thin heads. Hippopotamids are deeply nested within the family Anthracotheriidae. The oldest known hippopotamid is the genus Kenyapotamus, which lived in Africa from Kenyapotamus is known only through fragmentary fossils, but was similar in size to C. liberiensis. The Hippopotamidae are believed to have evolved in Africa, and while at one point the species spread across Asia and Europe, no hippopotami have ever been discovered in the Americas. Starting the Archaeopotamus, likely ancestors to the genus Hippopotamus and Hexaprotodon, lived in Africa and the Middle East. These species, though comparable in size to the pygmy hippopotamus, are considered dwarf hippopotamuses, rather than pygmies. They are likely descended from a full sized species of European hippopotamus, and reached their small size through the evolutionary process of insular dwarfism which is common on islands; the ancestors of pygmy hippopotami were also small and thus there was never a dwarfing process. Their lifespan in captivity ranges from 30 to 55 years, though it is unlikely that they live this long in the wild. The wide variety of plants pygmy hippos have been observed eating suggests that they will eat any plants available. This diet is of higher quality than that of the common hippopotamus.

The greatest threat to the remaining pygmy hippopotamus population in the wild is loss of habitat. The forests in which pygmy hippos live have been subject to logging, settling and conversion to agriculture, with little efforts made to make logging sustainable. As forests shrink, the populations become more fragmented, leading to less genetic diversity in the potential mating pool. Their meat is said to be of excellent quality, like that of a wild boar; unlike those of the common hippo, the pygmy hippo's teeth have no value. Some populations inhabit protected areas, such as the Gola Forest Reserve in Sierra Leone. Basel Zoo in Switzerland holds the international studbook and coordinates the entire captive pygmy hippo 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 to their nocturnal, forested existence, they were poorly known within their range as well. In Liberia the animal was traditionally known as a water cow. In 1927, Harvey Firestone of Firestone Tires presented Billy the pygmy hippo to U. S. President Calvin Coolidge. Coolidge donated Billy to the National Zoo in Washington, D. C. According to the zoo, Billy is a common ancestor to most pygmy hippos in U. S. zoos today. Several folktales have been collected about the pygmy hippopotamus. One tale says that pygmy hippos carry a shining diamond in their mouths to help travel through thick forests at night; by day the pygmy hippo has a secret hiding place for the diamond, but if a hunter catches a pygmy hippo at night the diamond can be taken. Villagers sometimes believed that baby pygmy hippos do not nurse but rather lick secretions off the skin of the mother.