Instruct: Given a question, retrieve relevant documents that answer the question.
Query: How much can a black wildebeest weigh?
The black wildebeest or white-tailed gnu (Connochaetes gnou) is one of the two closely related wildebeest species. It is a member of the genus Connochaetes and family Bovidae. It was first described in 1780 by Eberhard August Wilhelm von Zimmermann. The black wildebeest is typically 170–220cm (67–87in) in head-and-body length, and the typical weight is 110–180kg (240–400lb). Males stand about 111–121cm (44–48in) at the shoulder, while the height of the females is 106–116cm (42–46in). The black wildebeest is characterised by its white, long, horse-like tail. It also has a dark brown to black coat and long, dark-coloured hair between its forelegs and under its belly.
The black wildebeest is currently included in the same genus as the blue wildebeest (Connochaetes taurinus). This has not always been the case, and at one time the latter was placed under a separate genus of its own, Gorgon.[7] The black wildebeest lineage seems to have diverged from the blue wildebeest in the mid- to late Pleistocene, and became a distinct species around a million years ago.[8] This evolution is quite recent on a geologic time scale.[9]
At the PBD Canada 2011, Pathak was a speaker at the interactive panel discussion on engaging "Global Indians". He suggested that, to understand the global Indians, one should study (1.) monarch butterfly (multi-generation round trip between South and North America), (2.) blue wildebeest (survival of blue wildebeest over the black wildebeest that nearly were extinct), and the (3.) bees (how they are essential for existence of human life by being the pollination agent for plants). He described this approach as the "Three-B" approach to understanding how to engage the "Global Indians".
The blue wildebeest ("Connochaetes taurinus"), also called the common wildebeest, white-bearded wildebeest, or brindled gnu, is a large antelope and one of the two species of wildebeests. It is placed in the genus "Connochaetes" and family Bovidae, and has a close taxonomic relationship with the black wildebeest. The blue wildebeest is known to have five subspecies. This broad-shouldered antelope has a muscular, front-heavy appearance, with a distinctive, robust muzzle. Young blue wildebeest are born tawny brown, and begin to take on their adult colouration at the age of 2 months. The adults' hues range from a deep slate or bluish gray to light gray or even grayish brown. Both sexes possess a pair of large curved horns.
In the early 20th century, one species of the wildebeest, C. albojubatus, was identified in eastern Africa. In 1914, two separate races of the wildebeest were introduced, namely Gorgon a. albojubatus ("Athi white-bearded wildebeest") and G. a. mearnsi ("Loita white-bearded wildebeest"). However, in 1939, the two were once again merged into a single race, Connochaetes taurinus albojubatus. In the mid-20th century, two separate forms were recognised, Gorgon taurinus hecki and G. t. albojubatus.[12] Finally, two distinct types of wildebeest – the blue and black wildebeest – were identified. The blue wildebeest was at first placed under a separate genus, Gorgon,[13][14] while the black wildebeest belonged to the genus Connochaetes. Today, they are united in the single genus Connochaetes, with the black wildebeest being named (C. gnou) and the blue wildebeest (C. taurinus).[10]
The black wildebeest is particularly susceptible to anthrax, and rare and widely scattered outbreaks have been recorded and have proved deadly.[21] Ataxia related to myelopathy and low copper concentrations in the liver have also been seen in the black wildebeest.[22] Heartwater (Ehrlichia ruminantium) is a tick-borne rickettsial disease that affects the black wildebeest, and as the blue wildebeest is fatally affected by rinderpest and foot-and-mouth disease, it is also likely to be susceptible to these. Malignant catarrhal fever is a fatal disease of domestic cattle caused by a gammaherpesvirus. Like the blue wildebeest, the black wildebeest seems to act as a reservoir for the virus and all animals are carriers, being persistently infected, but showing no symptoms. The virus is transmitted from mother to calf during the gestation period or soon after birth.[23]
Black wildebeest are mainly active during the early morning and late afternoon, preferring to rest during the hottest part of the day.[26] The animals can run at speeds of 80km/h (50mph).[26] When a person approaches a herd to within a few hundred metres, the wildebeest snort and run a short distance before stopping and looking back, repeating this behaviour if further approached. They communicate with each other using pheromones detected by flehmen and several forms of vocal communication. One of these is a metallic snort or an echoing "hick", that can be heard up to 1.5 km (1 mi) away.[27] They are preyed on by the lion, spotted hyena, Cape hunting dog, leopard, cheetah, and crocodile. Of these, the calves are targeted mainly by the hyenas, while lions attack the adults.[2]
Before the arrival of Europeans in the area, wildebeest roamed widely, probably in relation to the arrival of the rains and the availability of good forage. They never made such extensive migrations as the blue wildebeest, but at one time, they crossed the Drakensberg Range, moving eastwards in autumn, searching for good pastures. Then they returned to the highvelds in the spring and moved towards the west, where sweet potato and Karoo vegetation were abundant. They also moved from north to south as the sourgrass found north of the Vaal River matured and became unpalatable, the wildebeest only consuming young shoots of sourgrass.[2] Now, almost all black wildebeest are in reserves or on farms, and the extent of their movements is limited.[1]
Black wildebeest are sexually dimorphic, with females being smaller in size and more slender than males.[2][14] The head-and-body length is typically between 170 and 220cm (67 and 87in). Males reach about 111 to 121cm (44 to 48in) at the shoulder, while females reach 106 to 116cm (42 to 46in).[15] Males typically weigh 140 to 157kg (309 to 346lb) and females 110 to 122kg (243 to 269lb). A distinguishing feature in both sexes is the tail, which is long and similar to that of a horse.[15] Its bright-white colour gives this animal the vernacular name of "white-tailed gnu", and also distinguishes it from the blue wildebeest, which has a black tail. The length of the tail ranges from 80 to 100cm (31 to 39in).[15]
The black wildebeest is known to hybridise with its taxonomically close relative, the blue wildebeest. Male black wildebeest have been reported to mate with female blue wildebeest and vice versa.[11] The differences in social behaviour and habitats have historically prevented interspecific hybridisation between the species, but hybridisation may occur when they are both confined within the same area. The resulting offspring is usually fertile. A study of these hybrid animals at Spioenkop Dam Nature Reserve in South Africa revealed that many had disadvantageous abnormalities relating to their teeth, horns, and the wormian bones in the skull.[12] Another study reported an increase in the size of the hybrid as compared to either of its parents. In some animals, the auditory bullae are highly deformed, and in others, the radius and ulna are fused.[13]
Blue wildebeest fossils dating back some 2.5 million years ago are common and widespread. They have been found in the fossil-bearing caves at the Cradle of Humankind north of Johannesburg. Elsewhere in South Africa, they are plentiful at such sites as Elandsfontein, Cornelia, and Florisbad.[17] The earliest fossils of the black wildebeest were found in sedimentary rock in Cornelia in the Orange Free State and dated back about 800,000 years.[16] Today, five subspecies of the blue wildebeest are recognized, while the black wildebeest has no named subspecies.[18][19]
Though they are not present in their natural habitat in such large numbers today, black wildebeest were at one time the main herbivores in the ecosystem and a main prey item for large predators such as the lion. Now, they are economically important for human beings, as they are a major tourist attraction, as well as providing animal products such as leather and meat. The hide makes good quality leather and the flesh is coarse, dry and rather hard.[26] Wildebeest meat is dried to make biltong, an important part of South African cuisine. The meat of females is more tender than that of males, and is at its best during the autumn season.[35] The wildebeest can provide 10 times as much meat as Thomson's gazelle.[36] The silky, flowing tail is used to make fly-whisks or chowries.[26]
The famed British sportsman known as the "Old Shekarry" wrote of how a black bear he shot in India probably weighed no less than 363kg (800lb) based on how many people it took to lift its body.[11] The largest Asiatic black bear on record allegedly weighed 200kg (440lb).[4] Zoo-kept specimens can weigh up to 225kg (496lb).[12] Although their senses are more acute than those of brown bears,[13] their eyesight is poor, and their hearing range is moderate, the upper limit being 30 kHz.[14]
Today, many wildebeest populations are experiencing rapid declines. Overland migration as a biological process requires large, connected landscapes, which are increasingly difficult to maintain, particularly over the long term, when human demands on the landscape compete. The most acute threat comes from migration barriers, such as fences and roads. In one of the more striking examples of the consequences of fence-building on terrestrial migrations, Botswanan authorities placed thousands of kilometres of fences across the Kalahari that prevented wildebeests from reaching watering holes and grazing grounds, resulting in the deaths of tens of thousands of individuals, reducing the wildebeest population to less than 10% of its previous size.[54] Illegal hunting is a major conservation concern in many areas, along with natural threats posed by main predators (which include lions, leopards, African hunting dogs, cheetahs and hyenas). Where the black and blue wildebeest share a common range, the two can hybridise, and this is regarded as a potential threat to the black wildebeest.[22]
Wildebeest provide several useful animal products. The hide makes good-quality leather and the flesh is coarse, dry and rather hard.[13] Wildebeest are killed for food, especially to make biltong in Southern Africa. This dried game meat is a delicacy and an important food item in Africa.[25] The meat of females is more tender than that of males, and is the most tender during the autumn season.[27] Wildebeest are a regular target for illegal meat hunters because their numbers make them easy to find. Cooks preparing the wildebeest carcass usually cut it into 11 pieces. The estimated price for wildebeest meat was about US$0.47 per kilogram around 2008.[55] The silky, flowing tail of the black wildebeest is used to make fly-whisks or chowries.[13]
This species of wildebeest seems to have evolved around 2.5 million years ago. The black wildebeest is believed to have diverged from the blue wildebeest to become a distinct species around a million years ago, in the mid- to late Pleistocene. Fossil evidence suggests that blue wildebeest were quite common in the Cradle of Humankind in the past. Apart from eastern Africa, fossils are commonly found in Elandsfontein, Cornelia, and Florisbad.
In a study of the feeding activities of a number of female black wildebeest living in a shadeless habitat, they fed mostly at night. They were observed at regular intervals over a period of one year, and with an increase in temperature, the number of wildebeest feeding at night also increased. During cool weather, they lay down to rest, but in hotter conditions they rested while standing up.[17]
Black wildebeest are predominantly grazers, preferring short grasses, but also feeding on other herbs and shrubs, especially when grass is scarce. Shrubs can comprise as much as 37% of the diet,[15] but grasses normally form more than 90%.[29] Water is essential,[30] though they can exist without drinking water every day.[31] The herds graze either in line or in loose groups, usually walking in single file when moving about. They are often accompanied by cattle egrets, which pick out and consume the insects hidden in their coats or disturbed by their movements.[2]
The black wildebeest is depicted on the coat of arms of the Province of Natal in South Africa. Over the years, the South African authorities have issued stamps displaying the animal and the South African Mint has struck a 5-rand coin with a prancing black wildebeest.[2][34]
Black wildebeest act as hosts to a number of external and internal parasites. A study of the animal in Karroid Mountainveld (Eastern Cape Province, South Africa) revealed the presence of all the larval stages of the nasal bot flies Oestrus variolosus and Gedoelstia hässleri. The first instar larvae of G. hässleri were found in large numbers on the dura mater of wildebeest calves, specially between June and August, and these later migrated to the nasal passages.[24] Repeated outbreaks of mange (scab) have led to large-scale extinctions.[2] The first study of the protozoa in blue and black wildebeest showed the presence of 23 protozoan species in the rumen, with Diplodinium bubalidis and Ostracodinium damaliscus common in all the animals.[25]
The blue wildebeest exhibits sexual dimorphism, with males being larger and darker than females. The blue wildebeest is typically in head-and-body length. The average height of the species is . While males weigh up to , females seldom exceed . A characteristic feature is the long, black tail, which is around in length. All features and markings of this species are bilaterally symmetrical for both sexes. The average life span is 20 years in the wild, and 21 years in captivity. The oldest known captive individual lived for 24.3 years.
In terms of skull length, the smallest subspecies of the blue wildebeest is the western white-bearded wildebeest. It is also the darkest subspecies; the eastern white-bearded wildebeest is the lightest race. Both subspecies possess a creamy white beard, whereas the beard is black in both the Nyassaland wildebeest and the common wildebeest. The longest muzzles are found in the Nyassaland wildebeest, and the shortest in female western white-bearded wildebeest.
The black wildebeest is depicted on the coat of arms of the Province of Natal in South Africa. Over the years, the South African authorities have issued several stamps displaying the animal and the South African Mint has struck a two cent piece with a prancing black wildebeest.[57]
The black wildebeest is a herbivore, and almost the whole diet consists of grasses. Water is an essential requirement. The three distinct social groups are the female herds, the bachelor herds, and the territorial bulls. They are fast runners, and communicate using a variety of visual and vocal communications. The primary breeding season for the black wildebeest is from February to April. A single calf is usually born after a gestational period of about 8.5 months. The calf remains with its mother until her next calf is born a year later. The black wildebeest inhabits open plains, grasslands, and Karoo shrublands.
However, black wildebeest can also affect human beings negatively. Wild individuals can be competitors of commercial livestock, and can transmit fatal diseases such as rinderpest, and cause epidemics among animals, particularly domestic cattle. They can also spread ticks, lungworms, tapeworms, flies, and paramphistome flukes.[6]