Przewalski’s horses have long been considered the last surviving wild horse species, but a recent study has raised speculations. The new data highlights a close genetic relationship between Przewalski’s horses and Botai horses, the latter of which some scientists consider to be the first domesticated species. They point to this relationship as evidence that Przewalski’s horses may have been domesticated.
However, Botai horses form a clade (or group of organisms with a common ancestor) distinct from domestic horses, meaning it is possible that Botai horses were tamed but not domesticated. Asian elephants offer a modern illustration of this distinction, as they have been tamed for use as draft and war animals for thousands of years but are not domesticated animals.
There is no strong evidence that Przewalski’s horses are feral descendants of domestic ancestors. Rather, they are unique descendants of horses within the Botai/Borly clade and represent genetic diversity that is no longer found among horses. As such, Przewalski’s horses remain the “best of the rest” of the true wild horses.
These horses ranged freely in wild populations well into the 20th century and are integral to a healthy steppe ecosystem. Their restoration and conservation continues to be a significant goal for global conservation and for preserving what remains of the world’s ancient wild horses.
Prior to reintroduction programs, Przewalski's horses were last seen in the wild during the 1960s in the Gobi Desert, which accounts for roughly the southern third of Mongolia. The number of Przewalski's horses dwindled due to human interference, including cultural and political changes, as well as military presence, poaching and capture. Today, their primary threats include habitat degradation, climate change, low genetic diversity, hybridizing and disease transmission. The loss of habitat is mainly due to to illegal miningand military disturbances.
Through breeding programs, Zooshave been instrumental inpreventing thePrzewalski's horse from dying out altogether. Ofthe approximately 1,900 Przewalski's horses alive today, all are descended from 14 founders that were caught in the wild between 1910 and 1960. The Smithsonian's National Zoo and Conservation Biology Institute is heavily involved in saving Przewalski's horses, including through reproductive research, genetic management of the North American herd, global genetic management, reintroduction and capacity building.
Species that are reduced to such small populations can lose much of their genetic diversity, which in turn can make adults less fertile and young less likely to survive. The species went through a second round of bottlenecking during World War II. In 1945,there were once again less than 20 breeding Przewalski's horses in the world. An international studbook was established in 1959, whichlater became the Species Survival Plan.
Przewalski'shorses are legally protected in Mongolia, where hunting has been prohibited since 1930. Three ongoing reintroduction sites are being monitored in Mongolia, including community integration and support. Despite the efforts already in place, there is still a need for better disease monitoring, separation between Przewalski's horses and domestic horses, streamlined population management, a better plan for Mongolia (home to the only wild population), genetic mapping of existing Przewalski's horses, addressing the concern of hybrids, trainingand education for those in the field.
