Przewalski's horse
- The tail of Przewalski's horses is not horse-like, but typical of donkeys: short-haired at the base and long-haired at the tip. A dark stripe runs from the withers to the tail, like in donkeys.
- The different number of chromosomes in Przewalski's horse and domestic horses raises doubts about its origin. Because of this difference, the previous belief that Przewalski's horse was the main ancestor of domestic horses now seems unlikely.
- The limited gene pool of Przewalski's horses leads to frequent inbreeding, which reduces their viability and reproductive ability. In captivity, this is worsened because wild horses in nature constantly move, covering many kilometers per day.
- Przewalski's horse has the highest brachycephalic index among domestic breeds. The index is highest in wild horses compared to any domestic horse breed.
- Przewalski's horse can live up to 38 years, which is the longest recorded lifespan for this species. In 2025, a horse named Branch in the Askania-Nova reserve reached this age, equivalent to about 170 human years.
- Botai horses are not direct ancestors of modern horses, as there has been no horse in the last 4000 years that could claim descent from them. Instead, modern domestic horses have a second wild ancestor, but the site of its domestication is still unknown.
- Hybrids of Przewalski's horses usually do not survive due to unsuitable food. They die or fail to reproduce because of poor nutrition.
- In a group of Przewalski's horses, the most experienced adult mare leads. The stallion stays at the rear and ensures no one falls behind.
- Domestic horses and Przewalski's horse can interbreed freely and produce fertile offspring, unlike other horse genus species hybridizations. Male hybrids of other horse genus species are always sterile.
- A Przewalski's horse stallion keeps the group together, and his authority in this is absolute. Mares reach sexual maturity at 3 years old, stallions — at 2.
Age
The Asian wild horse typically lives for 15 to 25 years, with a maximum recorded lifespan of 36 years and a theoretical lifespan ranging from 15 months and 1 week to 47 years. The species reaches sexual maturity between 1 year 11 months and 3 years 2 months; the young are born with their eyes open and begin walking immediately. During the embryonic stage, the fetus develops inside the mother and receives all necessary nutrients from her. The foal drinks its mother's milk, quickly stands, and learns to eat grass during the foal stage, which lasts from 1 day to 8 months. An adult horse lives in a herd, can reproduce, and independently finds food, with this adult stage lasting from 2 to 25 years.
Phenotype
The Asian wild horse’s embryo develops within the mother for almost eleven months. The young have light and soft fur, which helps retain warmth; their long legs allow them to run quickly after their mother within a few hours of birth. Adult Asian wild horses possess a robust body covered in dense, sandy-colored fur with a dark stripe along the back, and they have four strong hooves that enable rapid movement across hard ground and grass. The species has a short, stiff mane that stands erect and is dark in color, and a long tail with thick, dark hairs that helps to ward off insects.
Physiology
The Asian wild horse stands from 17 centimeters to 4.5 meters tall, with a body length ranging from 2 to 2.4 meters and a mass between 200 kilograms and 0.35 metric tons; the young have a body mass of 25 to 55 kilograms and a body length of 0.9 to 1.3 meters, while the adult stage presents a body mass of 0.25 to 0.35 metric tons and a body length of 2.1 to 2.4 meters.
Habitat
The species inhabits elevations from 800 meters to 2 kilometers above sea level and occupies several biomes, including temperate mixed forests with warm summers and abundant oaks, birches, and maples; flooded meadows where water frequently covers the ground and there is plentiful grass; and temperate steppes characterized by abundant grass and few trees, where rain occurs. The species' landscape consists of dry land and terrestrial forests, experiencing a variety of climates such as cold steppes with sparse trees and limited rainfall, consistently wet conditions with frequent rain and high humidity, warm summers with ample rain and snowfall in winter, snowy winters with cold temperatures, and steppes with abundant grass, few trees, and infrequent rainfall.
Shelter
The Asian wild horse inhabits open steppes and lacks permanent or long-term shelters. The species does not have fixed shelters, utilizing grasses and dry stems for resting. There is no permanent shelter for the Dzungarian horse.
Geography
The species is found within the biogeographical realms of Palearctic and Neotropical regions, inhabiting ecosystems such as the Tocantins-Pindare moist forests and the Mongolian-Manchurian steppes.
Feeding
Asian wild horses consume various grasses and plants of the steppe, grazing almost all day and chewing food with strong teeth; the species obtains food by biting grass with its teeth and feeds on grasses, grains, dry stems, grass, and grain. The feeding strategy involves grazing, and the daily food requirement ranges from 6 kilograms to 12 kilograms. In some cultures, the animal is eaten, but it is not considered kosher.
Reproduction
The species is a terrestrial animal, inhabiting and developing on land, away from bodies of water, and giving birth to live young that are not hatched from eggs or spawn. The female’s gestation period lasts eleven months and three weeks, resulting in a single foal, which she delivers on the ground. The mother feeds and protects the foal for several months. The species reproduces through homogamy, always with fertilization and without generational change. The size of the offspring is one. Maturity occurs from 2 to 5 years of age. The interval between breeding periods is from 1 to 2 years.