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Przewalski’s Horse: The Long Way Home
Przewalski’s Horse (Equus ferus przewalskii) (see also photos at end) is the last surviving species of wild horse – however, since 1969, it has been considered extinct in the wild. Because it was possible to continue breeding the remaining animals in captivity, the species could be preserved until today. “The current population goes back to a mere twelve horses that produced offspring while kept in zoos--a genetic bottleneck that carries the risk of diseases caused by inbreeding, such as a reduced resistance or shortened life expectancy,” explains Professor Hermann Ansorge, PhD, of the Senckenberg Research Institute and Natural History Museum in Görlitz, Germany, and he continues, “Under these conditions, attempts to reintroduce the Przewalski’s Horses into the wild pose a serious challenge. A species can only react to environmental changes if it has a high level of genetic variability!” In 1992, the first successful attempts began to reintroduce the Przewalski’s Horse into its former home, the Mongolian steppe. Today, about 746 individual horses can be found there in the wild again. In recent years, an international team took a closer look at the reintroduced Przewalski’s Horses and at historic collection materials. The researchers examined a total of 130 skulls from a period of 110 years. The comparison of non-metric characteristics revealed insights into the genetic variability. “This involves defined manifestations on the skull whose appearance can be differentiated qualitatively,” explains Dr. Ansorge, and he adds, “For example, these can be small natural openings that serve as passageways for blood vessels or nerves.