The African wild ass or African wild donkey (Equus africanus)
The African wild ass (Equus africanus) or African wild donkey is a wild member of the horse family, Equidae. This species is thought to be the ancestor of the domestic donkey (Equus asinus), which is sometimes placed within the same species. They live in the deserts and other arid areas of the Horn of Africa, in Eritrea, Ethiopia and Somalia. It formerly had a wider range north and west into Sudan, Egypt, and Libya. It is Critically Endangered, with about 570 individuals existing in the wild.
Equus africanus is a species of equid to which both domestic donkeys and African wild asses belong.
Equus africanus is a species of the genus Equus of the ungulate family Equidae. Its domesticated form has played an important historical role in the development of human economy and culture. About 4.4-4.5 million years ago, according to geneticists, the Equus lineage originated that gave rise to all modern horses, zebras and donkeys.
Description
Unlike the horse, the donkey has hooves adapted to rocky and uneven terrain. They help to move more safely, but are not suitable for fast galloping. However, a donkey can sometimes reach speeds of up to 70 km/h (43 mph). Donkeys come from countries with an arid climate. Their hooves do not cope well with the humid European climate and often form deep cracks and holes, which hide sources of rot. This is why caring for donkeys' hooves is extremely important. To be fair, they are shod less frequently than horses.
Donkeys can have grey, brown or black coats, white breeds being rare. The belly is usually light, as is the front of the muzzle and the area around the eyes. Donkeys have a stiff mane and a tail ending in a tassel. The ears are much longer than those of a horse. A narrow dark stripe runs down the back. Some subspecies sometimes have more stripes: one on the shoulders and several on the legs.
Depending on the breed, they reach a height of 90-160 cm and reach sexual maturity at 2-2.5 years. In principle, mating is possible all year round, but usually takes place in spring. After a gestation period of 12 to 14 months, one or two offspring are born, which become independent at the age of 6 to 9 months.
Peculiarities
In addition to the external differences from horses, there are also some characteristics that are not visible at first glance. One of them is the different number of vertebrae. In addition, donkeys have only 31 pairs of chromosomes, while horses have 32. Donkeys have a slightly lower body temperature, with an average of 37 °C instead of 38 °C. Donkeys also have a shorter period of time than horses. Donkeys also have a longer gestation period.
Wild and feral populations
As with horses, a distinction has to be made between wild and feral donkeys. The different subspecies of wild donkeys once lived in North Africa and Asia Minor, but as a result of domestication they almost disappeared by Roman times. In modern times, they have survived only in Ethiopia, Eritrea, Djibouti, Somalia and Sudan; a small population has managed to take root in a nature reserve in Israel. In the 1980s the total population of wild asses was estimated to be in the thousands and has since declined further. In Somalia, wild asses have probably been completely wiped out as a result of civil war and lawlessness; in Ethiopia and Sudan they are likely to suffer the same fate in the near future. The only country with a relatively stable wild donkey population is Eritrea, with about 400 animals.
Unlike the original Equus africanus, ex-domesticated Equus africanus exist in many regions of the world. Their range includes countries that still have wild donkeys, which zoologists fear could lead to the two groups mixing and destroying the "genetic purity" of Equus africanus. About 1.5 million feral donkeys roam the steppes of Australia. In the southwestern United States there are about 6,000 feral donkeys, called burros, which are protected. One of the few European populations of Equus africanus is found in Cyprus on the Karpas peninsula. They are dark brown or black in colour and noticeably larger than other donkeys. They usually have zebra stripes on their legs.
Taxonomy
Different authors consider the African wild ass and the domesticated donkey one or two species; either view is technically legitimate, though the former is phylogenetically more accurate. However, the American Society of Mammalogists classifies the donkey as a distinct species, as it does with almost all domestic mammals.
The species name for the African wild ass is sometimes given as asinus, from the domestic donkey, whose specific name is older and usually would have priority. But this usage is erroneous since the International Commission on Zoological Nomenclature has conserved the name Equus africanus in Opinion 2027. This was done to prevent the confusing situation of the phylogenetic ancestor being taxonomically included in its descendant.
Thus, if one species is recognized, the correct scientific name of the donkey is E. africanus asinus.
The first published name for the African wild ass, Asinus africanus, Fitzinger, 1858, is a nomen nudum. The name Equus taeniopus von Heuglin, 1861 is rejected as indeterminable, as it is based on an animal that cannot be identified and may have been a hybrid between a domestic donkey and a Somali wild ass; the type has not been preserved. The first available name thus becomes Asinus africanus von Heuglin & Fitzinger, 1866. A lectotype is designated: a skull of an adult female collected by von Heuglin near Atbarah River, Sudan, and present in the State Museum of Natural History Stuttgart, MNS 32026.
The three subspecies recognized:
- Nubian wild ass Equus africanus africanus (von Heuglin & Fitzinger, 1866) - Nubian Desert of northeastern Sudan, from east of the Nile River to the Red Sea and south to the Atbarah River and northern Eritrea.
- Somali wild ass Equus africanus somaliensis (Noack, 1884) – Somalia, Somaliland, Eritrea and Ethiopia.
- †Atlas wild ass Equus africanus atlanticus (P. Thomas, 1884) - Region around the Atlas Mountains, across modern day Algeria, Tunisia and Morocco.
Behavior
The African wild ass is primarily active in the cooler hours between late afternoon and early morning, seeking shade and shelter amongst the rocky hills during the day. The Somali wild ass is also very agile and nimble-footed, capable of moving quickly across boulder fields and in the mountains. On the flat, it has been recorded reaching speeds of 70 km/h (43 mph). In keeping with these feats, its soles are particularly hard and its hooves grow very quickly.
Mature males defend large territories around 23 square kilometres in size, marking them with dung heaps – an essential marker in the flat, monotonous terrain. Due to the size of these ranges, the dominant male cannot exclude other males. Rather, intruders are tolerated – recognized and treated as subordinates, and kept as far away as possible from any of the resident females. In the presence of estrous females, the males bray loudly. These animals live in loose herds of up to fifty individuals.
In the wild, African wild ass breeding occurs during the wet season. The gestation period lasts for 11 to 12 months, and one foal is born during the period from October to February. The foal weans for 6 to 8 months after birth, reaching sexual maturity at the age of 2 years. Lifespan is up to 40 years in captivity.
Wild asses can run swiftly, almost as fast as a horse. However, unlike most hoofed mammals, their tendency is to not flee right away from a potentially dangerous situation, but to investigate first before deciding what to do. When they need to, they can defend themselves with kicks from both their front and hind legs. Equids were used in ancient Sumer to pull wagons circa 2600 BC, and then chariots on the Standard of Ur, circa 2000 BC. These have been suggested to represent onagers, but are now thought to have been domesticated asses.
Diet
The African wild asses' diet consists of grasses, bark, and leaves. Despite being primarily adapted for living in an arid climate, they are dependent on water, and when not receiving the needed moisture from vegetation, they must drink at least once every three days. However, they can survive on a surprisingly small amount of liquid, and have been reported to drink salty or brackish water.
Conservation status
Though the species itself is under no threat of extinction, due to abundant domestic stock (donkeys and burros), the two extant wild subspecies are both listed as critically endangered. African wild asses have been captured for domestication for centuries and this, along with interbreeding between wild and domestic animals, has caused a distinct decline in population numbers. There are now only a few hundred individuals left in the wild. These animals are also hunted for food and for traditional medicine in both Ethiopia and Somalia. Competition with domestic livestock for grazing, and restricted access to water supplies caused by agricultural developments, pose further threats to the survival of this species. The African wild ass is legally protected in the countries where it is currently found, although these measures often prove difficult to enforce. A protected population of the Somali wild ass exists in the Yotvata Hai-Bar Nature Reserve in Israel, to the north of Eilat. This reserve was established in 1968 with the view to bolster populations of endangered desert species. Populations of horses and asses are fairly resilient and, if the species is properly protected, it may well recover from its current low.
In captivity
There are about 150 individual Somali wild asses living in zoos around the globe, of which 36 were born at Zoo Basel, where this species' breeding program started with Basel's first Somali wild asses in 1970 and the first birth in 1972.
Zoo Basel manages the European studbook for the Somali wild ass and coordinates the European Endangered Species Programme (EEP). All European wild donkeys are either descendants of the original group at Zoo Basel or of 12 others that came from the Yotvata Hai-Bar Nature Reserve in Israel in 1972.
