Przewalski's gazelle

Przewalski's gazelles are relatively small, slender antelopes with large eyes and short, pointed ears. The nasal bones are relatively large, suggesting an adaptation to the thin air of the Tibetan plateau. They have a head and body length of , a shoulder height of , and weigh between . Males are generally larger and heavier than the females. The tail is short, measuring only , and is often entirely hidden by fur. The animal is yellowish brown with a white underside and a white heart-shaped patch on its rump, partially bisected by a light brown vertical line. Males are darker in colour than females, and the coat of both sexes is more noticeably greyish in winter. The fur lacks an undercoat, consisting only of dense guard hairs. Male Przewalski's gazelles have ridged horns, which rise between the eyes and curve inwards at the tips; in younger males, the tips may actually touch, but they diverge as the animal ages. In the adult, the horns reach in length. The females are hornless. Przewalski's gazelle is similar in appearance to both the Tibetan gazelle and the Mongolian gazelle, to both of which it is closely related, and occurs in similar geographic areas. It is intermediate in size between the other two species, and can most easily be distinguished from them by the shape of its horns. ==Distribution and habitat==

Until the early 20th century, Przewalski's gazelle was widespread across the high plateaus of northwestern China and Inner Mongolia. However, it is now found only in a single small area around Qinghai Lake, having been extirpated across the great majority of its former range. It inhabits flat open valleys and steppeland between mountains, and the sand dunes and semi-desert zones around lakes. Two sub-species have been described, although one is now believed to be extinct: • P. przewalskii przewalskii - Qinghai • P. przewalskii diversicornis † - Gansu and the Ordos Loop region ==Behaviour and ecology==

The preferred diet of Przewalski's gazelles consists of sedges and grasses, supplemented by herbs and shrubs such as Astragalus. The diet of Przewalski's gazelles has remained largely unchanged since the Early Holocene, as evidenced by analyses of both enamel δ13C and dental microwear of Przewalski's gazelle specimens from the Qinghai Lake Basin dating back to between 8900 and 7900 BP. Like modern Przewalski's gazelles, they were primarily grazers of C3 grasses. The gazelle usually travels in small groups, with rarely more than a dozen individuals, although much larger herds were reported in the 19th century, when the overall population was higher. Males are often solitary or travel in small groups of two or three individuals for much of the year, but gather together in small herds with the females during the winter rut. Przewalski's gazelles are generally quiet, but have been reported to make short bleating sounds. ==Reproduction==

Przewalski's gazelles rut from late December to early January. Males scent mark small territories and clash with rivals, fighting with their horns. Females have also been observed fighting for access to males. Courtship consists of the male moving towards the female while standing on his hind legs, and is followed by a brief copulation. Gestation lasts around six months, so that the young are born around May or June. The mother gives birth to a single offspring, usually in thickets or areas of tall grass, where they can be concealed from potential predators. The young are able to follow their mother within a few minutes of birth, although they may remain concealed for a few days before rejoining the herd. Females become fertile during their second year, around 18 months of age. The lifespan of Przewalski's gazelles is unknown, although based on that of related species, it is probably around eight years. ==Conservation==

Przewalski's gazelle is perhaps one of the most endangered species of large mammal on Earth. The many threats against the species include competition with domestic livestock and fencing of the natural habitat. These problems have become exacerbated as the area is increasingly developed as agricultural land. ==See also==