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viernes, 22 de agosto de 2008

Nsui-fisi or king Cheeta

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Mutants are natural variations which occur due to spontaneous genetic changes or the expression of recessive (hidden) genes. Albinism (pure white), chinchilla (white with pale markings) and melanism (black) are the commonest mutations. Erythristic (red), leucistic (partial albinism/cream) and maltesing (blue) are also been reported. Sometimes the markings are aberrant e.g. too sparse or too heavy (abundism), giving the appearance of a pale or dark individual. Numerous colour and pattern mutations occur in domestic cats so why are they less common in big cats? Wild cats displaying these traits may be less likely to survive to pass on the traits. In captivity, humans control which traits are bred, hence the multitude of domestic cat colours and types. In the wild, nature selects against any trait which does not enhance the animal's survival chances.

In the past, the obvious reaction to any unusual big cat was to shoot it for the trophy room. As a result, many interesting mutations may have been wiped out before the genes were passed on. Some colour mutations which would disadvantage a wild big cat are bred in captivity and are not viable in the wild. It is questionable whether these mutants should be perpetuated for the sake of curiosity or aesthetics alone.

Some of the information here may also be found in "Mystery Cats of the World" and assorted articles by Karl Shuker. I am grateful to Paul McCarthy for researching and providing extensive material and references.

The king cheetah is a mutant form of cheetah. This may be a form of abundism where spots coalesce into swirls. Alternatively, it may be that cheetahs can also be striped as well as spotted (like blotched tabby and spotted tabby cats). The blotched tabby was one of the first pattern mutations in the domestic cat so it would not be unusual to see this pattern mutation appearing in other cat species. It was originally believed to be a new species of cheetah or a cheetah/leopard hybrid, but is now believed to be a relatively recent mutation. The identity of the king cheetah was not resolved until researchers noticed that some cheetah litters contained both striped individuals and spotted individuals. The darker patten may give better camouflage in less open territory and it has been suggested that evolution is allowing cheetahs to exploit new habitats.

The king cheetah, a cheetah with black stripes along its back and swirls and splotches instead of spots, was first noted in Zimbabwe in 1926. In 1927, the naturalist Pocock declared it a separate species, but reversed this decision in 1939 due to lack of evidence. In 1928, a skin purchased by Lord Rothschild was found to be intermediate in pattern between the king cheetah and spotted cheetah and Abel Chapman voiced the opinion that it was a colour form of the spotted cheetah. 22 skins were found between 1926 and 1974. Since 1927, king cheetahs were reported 5 further times and though strangely marked skins had come from Africa, a live king cheetah was not photographed until 1974 in South Africa's Kruger National Park. Cryptozoologists Paul and Lena Bottriell mounted expeditions to find the king cheetah, finally photographing one in 1975. They also managed to obtain stuffed specimens. The king cheetah appeared larger than a spotted cheetah and its fur had a different texture. There was another wild sighting in 1986 - the first for 7 years. By 1987, 38 specimens had been recorded, many from pelts.

However, the king cheetah was already known to natives and its existence had been pooh-poohed by white hunters and settlers. In 1937, Captain W Hichens, Late of the Intelligence and Administrative Services, East Africa, wrote in African Mystery Beasts. (Discovery (Dec): 369-373) wrote: Nor is the African native a fool in the ways of the bushveld and its beasts; he does not assert that a beast is an mngwa when any old woman in the kraal could tell by a glance at its spoor or by the way it attacked that it is a lion, a leopard or a hyæna. Native hunting lore clearly dis-tinguishes the bush beasts. One well-known hunting-song tells of the simba (lion), nsui (leopard) and the mngwa all in one verse plainly showing that there is no confusion in the native mind between these three great carnivores. Moreover, many white hunters, settlers and officials, whose bona fides cannot be doubted, have spoored, heard, shot at and sometimes even seen and grappled with these mystery monsters; and very occasionally one of the "mythical" beasts is shot or trapped, as happened with the nsui-fisi recently. Then the natives say, "We told you so!" and zoologists scratch their heads and mutter, "ex Africa semper, etc.!"

[...]It is not impossible that the khodumodumo may yet prove to be an animal hitherto unknown. The nsui-fisi was a brute of a similar kind. Its name means " leopard-hyæna," and many hair-raising tales are to be heard of it in Rhodesian kraals. For many years natives have told white hunters of this beast, averring that it was incredibly cunning, swift and ferocious, as one would expect of a hybrid " killer" combining a leopard's ferocity with the hyæna's slinking guile. It always attacked, the kraalsmen said, at night, and smashed its way through the flimsy doors or roofs of stock-pens, making off with goats and sheep, and often turning the pens into a veritable shambles. It was like a leopard, the natives declared, but instead of being spotted, it was barred, white and black, like a zebra, and not unlike a striped hyena. But no such beast was known to white hunters and so the nsui-fisi was pooh-poohed into the limbo of "it's just native superstition, of course!"

In this case, however, the native was right. No less an authority than Mr. R. I. Pocock was able to lay on the table of the Zoological Society not long ago, a skin of the nsui-fisi, one of a number obtained in Rhodesia. It was shown to be a new species of cheetah (Acinonyx rex), not spotted, but striped like a zebra, as the kraalsmen had been saying for many years! As Mr. Pocock remarked, it was "most extraordinary that so large and distinct a species should remain for so long unknown." The natives were wrong in supposing the nsui-fisi to be a leopard-hyaena cross, but that is certainly what it looks like to anyone other than a skilled zoologist. It would thus be rash to assert that other "mythical beasts" like the nsui-fisi cannot exist, and it is by no means impossible that the mngwa, kerit, and ndalawo may yet prove to be as real. By description all these beasts are well known.

The question of its identity was resolved (for Europeans) in the 1981 when king cheetahs were born to spotted cheetah parents at the De Wildt Cheetah Center in South Africa. In May 1981, two sisters gave birth there and each litter contained one king cheetah. The sisters had both been mated to a wild-caught male from the Transvaal area (where King Cheetahs had been recorded) and further King Cheetahs were later born at the Centre. The gene is recessive, meaning it is carried hidden in some spotted cheetahs. When two carriers mate, there is a chance that some offspring will inherit two copies of the hidden gene and be king cheetahs. King cheetahs mated together will produce king cheetahs. This cheetah mutation has been reported in Zimbabwe, Botswana and in the northern part of South Africa's Transvaal province. There are probably only a handful of king cheetahs in the wild, but it has been bred in captivity. As with the selective breeding of white tigers and white lions, there is a danger of inbreeding - since cheetahs are already so inbred (causing infertility problems), this could be disastrous. The king cheetah is disadvantaged when stalking prey on the open plain, but less so in areas where it can begin its sprint from dappled shade.

Woolly cheetahs with longer, denser fur have occurred several times and were thought to be a separate species. They were shot rather than captured alive so the mutation has vanished. They had thicker bodies and stouter limbs than normal cheetahs (this may be a trick of the long hair) with dense, woolly hair especially on the tail and neck where it formed a ruff or mane. The long fur made the normal spotted cheetah pattern indistinct and it appeared pale fawn with dark, round blotches. In domestic cats, the markings of longhairs are less distinct than those of shorthairs due to the blurring effect of longer fur. In domestic cats, long hair is due to a recessive gene, so the gene may still be present in the cheetah gene pool. The cheetah gene pool, however, is not as diverse as the gene pools of most other cat species. The painting of the woolly cheetah (shown below) suggests not only a longhaired cheetah, but a red (erythristic) cheetah.


In 1877, Philip Sclater of the Zoological Society of London wrote of a recent acquisition by the zoo: "It presents generally the appearance of a cheetah, but is thicker in the body, and has shorter and stouter limbs, and a much thicker tail. When adult it will probably be considerably larger than the cheetah, and is larger even now than our three specimens of that animal. The fur is much more woolly and dense than in the cheetah, as is particularly noticeable on the ears, mane, and tail. The whole of the body is of a pale isabelline [yellowish-fawn] colour, rather paler on the belly and lower parts, but covered all over, including the belly, with roundish dark fulvous blotches. There are no traces of th black spots which are so conspicuous in all of the varieties of the cheetah which I have seen, nor of the characteristic black line between the mouth and eye." Although described as blotched, the painting depicts it as freckled. In 1878, a second woolly cheetah was reported as a preserved specimen in the South African Museum. Both the London and South African specimens had come from Beaufort West. In 1884, a third skin was obtained from the same area, though this had more distinct spots and was a little smaller. Sadly, by the 1880s, the trophy hunters had eliminated the woolly cheetah.

In Harmsworth Natural History (1910), R Lydekker wrote of the "hunting leopard" or "chita", as the cheetah was then known: "The hunting leopard of South Africa has been stated to differ from the Indian animal in its stouter build, thicker tail, and denser and more woolly fur, the longest hairs occurring on the neck, ears, and tail. This woolly hunting leopard was regarded by its describer as a distinct species (Cynaelurus lanius), but it is, at most, only a local race, of which the proper name is C. jubatus guttatus."

The Moghul Emperor of India, Jahangir, recorded having a white cheetah presented to him in 1608. In the memoirs of Tuzuk-i-Jahangiri, the Emperor says that in the third year of his reign: "Raja Bir Singh Deo brought a white cheetah to show me. Although other sorts of creatures, both birds and beasts have white varieties .... I had never seen a white cheetah. Its spots, which are (usually) black, were of a blue colour, and the whiteness of the body also inclined to blue-ishness." This indicates the chinchilla mutation which restricts the amount of pigment on the hair shaft. Although the spots would have been formed of black pigment, the less dense pigmentation (it does not go all the way to the root of the hair) would have produced a hazy, bluish effect. As well as Jahangir's white cheetah at Agra, a report of "incipient albinism" has come from Beaufort West according to Guggisberg. The two sketches below show an isabelline cheetah and a maltese (blue) cheetah ("isabelline" means yellowish-fawn; maltese means "slate grey").

As well as the possibly red longhaired cheetah shown here, different coloured cheetahs have sometimes occurred. Melanistic (black) and albino (white) cheetahs have been reported. Black cheetahs are all black with ghost markings (Stoneham, 1925). In a letter to "Nature in East Africa", HF Stoneham reported a melanistic cheetah in the Trans-Nzoia District of Kenya in 1925. Vesey Fitzgerald saw a melanistic cheetah in Zambia in the company of a spotted cheetah. Red (erythristic) cheetahs have dark tawny spots on a golden background. Cream (or isabelline) cheetahs appear to be a further dilution of red with pale red spots on a pale background. Blue (or grey) cheetahs have variously been described as white cheetahs with grey-blue spots (chinchilla) or pale grey cheetahs with darker grey spots (maltese mutation). Some desert region cheetahs are unusually pale; probably they are better camouflaged and there

A cheetah with hardly any spots was shot in Tanzania on 1921 (Pocock), it had only a few spots on the neck and back and these were unusually small. This is possibly the same mutation which causes ticked (Abyssinian-type pattern) cats; any markings are restricted to the face, legs and tail with possibly some thin stripes around the neck and barring on the legs. The background colour remains the normal colour, it is just the pattern which is missing.

Cheetahs show less variety in their type than do many other types of big cat due to a genetic bottleneck. The DNA of all modern cheetahs is so similar that it is thought that all cheetahs are descendants of a single mother and cubs. This inbreeding means little genetic variation, poor fertility and increased susceptibility to disease. The appearance and perpetuation of the blotched (king) cheetah is highly significant as it suggests that gene mutations are occurring and that cheetahs may become more genetically diverse in the future.

fore better hunters and more likely to breed and pass on their paler colouration.


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