'The history of ligers dates Essay\r'

'The history of ligers dates to at least the advance(prenominal) nineteenth century in India. In 1798, Étienne Geoffroy Saint-Hilaire (1772â€1844) made a emblazon plate of the upshot of a king of beasts and a tiger. In 1825, G. B. Whit make startr made an engraving of liger cubs innate(p) in 1824.[3] The p bents and their three liger young argon as well depicted with their trainer in a 19th-century ikon in the naïve style.\r\nTwo liger cubs born in 1837 were exhibited to King William IV and to his successor Queen Victoria. On 14 December 1900 and on 31 whitethorn 1901, Carl Hagenbeck wrote to zoologist James Cossar Ewart with details and photographs of ligers born at the Hagenbeck’s Tierpark in Hamburg in 1897. In wight Life and the dry land of Nature (1902â€1903), A.H. Bryden described Hagenbeck’s â€Å" king of beasts-tiger” loan-blends: It has remained for star of the most enterprising collectors and naturalists of our time, Mr. Carl H agenbeck, non yet to breed, scarce to bring successfully to a hefty maturity, specimens of this noble-minded every last(predicate)iance between those devil grand and formidable felidae, the lion and tiger.\r\nThe illustrations will indi honke sufficiently how fortunate Mr. Hagenbeck has been in his efforts to nonplus these marks. The oldest and biggest of the zoologys shown is a inter breed born on the 11th whitethorn, 1897. This fine beast, forthwith more than five historic period old, equals and even excels in his proportions a well- amazen lion, measuring as he does from prise tip to tail 10 ft 2 inches in aloofness, and standing further three inches elfin than 4 ft at the shoulder. A straightforward big lion will weigh nighwhat 400 lb […] the crown of thorns in question, measure as it does no less than 467 lb, is certainly the higher-up of the most well- developn lions, whether wild-bred or born in a menagerie.\r\nThis animal shows faint striping and mottling, and, in its characteristics, exhibits self-colored traces of both its leavens. It has a somewhat lion-like head, and the tail is more like that of a lion than of a tiger. On the other(a) hand, it has no trace of mane. It is a broad and really powerful beast.[4] In 1935, four ligers from two litters were re ared in the zoological Gardens of Bloemfontein, South Africa. Three of them, a manful and two womanishs, were still donjon in 1953. The antheral weighed 340 kg (750 lb) and stood a foot and a half(prenominal) (45 cm) taller than a full parentn virile lion at the shoulder. Although ligers are more normally be than tigons today, in At Home In The Zoo (1961), Gerald Iles wrote â€Å"For the record I must formulate that I contrive n forever seen a liger, a hybrid obtained by soft touching a lion with a tigress. They seem to be even rarer than tigons.”\r\n size and harvesting The liger is often believed to represent the deepst known cat in the wo rld.[1] viriles r severally a total length of 3 to 3.5 m,[6][7] meaning they are the size of bad Siberian tiger young-begetting(prenominal)s.[8] Imprinted genes whitethorn be a factor contributing to huge liger size.[9]\r\nThese are genes that may or may non be uttered on the parent they are familial from, and that at times play a role in issues of hybrid growth. For example, in some dog breed crosses, genes that are expressed solitary(prenominal) when gibernally-inherited baffle the young to grow slap-up(p)r than is typical for any parent breed. This growth is not seen in the paternal breeds, as much(prenominal) genes are normally â€Å"counteracted” by genes inherited from the feminine of the appropriate breed.[10] Other big cat hybrids potentiometer reach similar sizes; the litigon, a rare hybrid of a phallic lion and a womanly tiglon, is roughly the same size as the liger, with a male named Cubana drop (at the Alipore Zoo in India) reaching 363 kg (800 lb ).[11]\r\nThe extreme rarity of these second-generation hybrids may make it uncorrectable to ascertain whether they are larger or little, on add up, than the liger. It is wrongly believed that ligers continue to grow throughout their lives repayable to hormonal issues.[citation needed] It may be that they simply grow far more during their growing years and take farseeinger to reach their full adult size.\r\n yet growth in shoulder height and personify length is not seen in ligers over 6 years old, same as both lions and tigers. Male ligers also have the same levels of testosterone on average as an adult male lion, yet areazoospermic in abidance with Haldane’s rule. In appendix, female ligers may also attain great size, weighing approximately 320 kg (705 lb) and reaching 3.05 m (10 ft) long on average, and are often fertile. In contrast,pumapards (hybrids between pumas and leopards) be given to exhibit dwarfism. Hercules and Sinbad[\r\nJungle Island, an interactive ani mal tooth root park in Miami, is home to a liger named Hercules, the largest non-obese liger, who is recognized by the Guinness Book of World Records as the largest living cat on Earth, weighing over 410 kg (904 lb).[12] Hercules was featured on the Today Show, Good first light America, Anderson Cooper 360, Inside Edition and in a Maxim article in 2005, when he was hardly three years old and already weighed 408.25 kg (900 lb). Hercules is healthy and is expected to live a long life. The cat’s breeding is said to have been a complete accident. Sinbad, another liger, was shown on the issue Geographic Channel. Sinbad was reportedly similar in free weight to Hercules.\r\nLongevity[Shasta, a ligress (female liger) was born at the Hogle Zoo in Salt Lake City on 14 May 1948 and died in 1972 at age 24.[citation needed] Valley of the Kings animal sanctuary in Wisconsin had a male liger named corner who weighed around 550 kg (1,213 lb), and died in 2007, at 21 years old. Hobbs, a male liger at the sierra Safari Zoo in Reno, Nevada, lived to almost 15 years of age before succumbing to liver ruin and weighed in at 410 kilograms (900 lb). Fertility\r\nThe fertility of hybrid big cat females is well documented crossways a number of several(predicate) hybrids. This is in accordance with Haldane’s rule: in hybrids of animals whose sex is located by sex chromosomes, if one sex is absent, rare or stereotypical, it is the heterogametic sex (the one with two different sex chromosomes e.g. X and Y). According to Wild Cats of the World (1975) by C. A. W. Guggisberg, ligers and tigons were long thought to be sterile: in 1943, a fifteen-year-old hybrid between a lion and an ‘Island’ tiger was successfully mated with a lion at the Munich Hellabrunn Zoo. The female cub, though of sharp health, was raised to adulthood.[13] In September 2012, the Russian Novosibirsk Zoo announced the birth of a â€Å"liliger”, which is the outcome of a liger mother and a lion father. The cub was named Kiara.\r\n appearance\r\nColour plate of the offspring of a lion and tiger, Étienne Geoffroy Saint-Hilaire Ligers have a tiger-like striped ruler that is very(prenominal) faint upon a lionesque tawny background. In addition they may inherit rosettes from the lion parent (lion cubs are rosetted and some adults retain faint markings). These markings may be blue, dark brown or sandy. The background colour may be correspondingly tawny, sandy or golden. In common with tigers, their underparts are blench. The actual pattern and colour depends on which wash the parents were and on how the genes interact in the offspring.\r\nWhite tigers have been crossed with lions to produce â€Å"white” (actually pale golden) ligers. In theory, white tigers could be crossed with white lions to produce white, very pale or even stripeless ligers. there are no black ligers. Very few melanistic tigers have ever been recorded, most being due to exc essive markings (pseudo-melanism or abundism) rather than true melanism; no reports of black lions have ever been substantiated. As blue or Maltese Tigers probably no longer exist, colorize or blue ligers are exceedingly improbable. It is not insufferable for a liger to be white, but it is very rare\r\nLigers in the wild:\r\nIt is unlikely a mating of this type would ever occur in the wild, for a number of reasons. Firstly, lion and tiger habitats do not act, though you’ll often hear claims that they lick in one area of the world, this being the Gir guinea pig Park and king of beasts Sanctuary in Bangladesh. The rectitude is tigers are not found within one hundred miles of Gir Forest. Within the sanctuary itself is the only lion subspecies found outside of Africa. This is the very rare Asian lion (only a few hundred remain and they face extinction). The lion rules in Gir Forest and no tigers are found there.\r\nTigers are not found in Africa, and are restricted to As ia. Though it is reasonable that a tiger may cross into lion territory, both species are so rare that it is extremely unlikely the two would ever meet. On chair of this, the Gir Forest is surrounded by farming and agriculture. The lions within the sanctuary are effectively captive in the wild and tigers do not like to cross large stretches of open ground. What would happen if the two species did meet? The very solitary tiger would be little inclined to join in with the more amicable pride of lions. Apart from periods of mating, tigers even go out of their way to avoid their own species.\r\nThe Tigon is a hybrid cross between a male Tiger and a female Lion wherefore ARE LIGERS SO MUCH BIGGER THAN TIGONS?\r\nThe large size of the liger and small size of the tigon is due to â€Å"genomic imprinting” †the unequal expression of genes depending on parent of origin i.e. whether certain growth genes are inherited from the male or the female. This is linked to the speciesâ⠂¬â„¢ lifestyle and breeding strategy †whether the female mates with only one male while in rouse (non- free-enterprise(a)) or whether she mates with some males ( paralleled). This results in â€Å"growth dysplasia”. The adjacent explanation is greatly simplified as a number of other genes are contributed unequally by the male and female parents and also affect the normal health and longevity of the offspring. Lions live in prides lead by several adult males. The lionesses mate with each of those males. Each male wants his offspring to be the ones to survive, but the female’s genes want multiple offspring to survive.\r\nThe father’s genes promote size of the offspring to ensure that his offspring out-compete any other offspring in the uterus at the same time. Genes from the female inhibit growth to ensure that as umteen offspring as possible survive and that they all have an equal chance. By contrast, tigers are by and large solitary and a female on heat normally only mates with one male. in that respect is no competition for space in the womb so the male tiger’s genes do not need to promote larger offspring. There is therefore no need for the female to compensate, so the offspring’s growth goes uninhibited.\r\nWhen a male lion mates with a tigress, his genes promote large offspring because lions are change to a competitive breeding strategy. The tigress does not inhibit the growth because she is bowdlerizeed to a non-competitive strategy. Therefore the offspring (liger) grows larger and stronger than either parent because the effects do not part each other out. Ligers take several years to reach full adult size, but it is a myth that ligers never stop growing. When a male tiger mates with a lioness, his genes are not promoting large growth of the offspring because he is adapted to a non-competitive breeding strategy. However, the lioness is adapted to a competitive strategy and her genes inhibit the growth of the offspring.\r\nThis uneven match means that the offspring (tigons) are often smaller and less robust than either parent. Growth dysplasia has other effects: the size of the placenta may be touched (causing miscarriage), the embryo may be aborted at an early stage due to abnormal growth, the cub may be stillborn or may only survive a few days. In some rodents, mating Species A males with Species B females produces offspring half normal size, but mating Species B males with Species A females cause the offspring to be aborted as they fork out to grow to several times the normal size.\r\nBecause of the impossible action of a gene being inherited from only females, there is a competing supposition. This hypothesis (allthough not tested) is that the Lion’s sperm is damaged somehow during medical dressing and that a growth inhibiting gene is typically destroyed. It is impossible for a gene carried on a chromosomes to be passed along only from the mother.\r\nThe reason for th is is there are no chromosomes that only a female can have. Female Tigons and Female Ligers both possess a tiger X chromosme and a lion X chromosome, yet only the female Ligers will grow large, this means something must happen to either alter the genes or that the cause of the growth dysplasia lies at least partially outside of the genes. Another possible hypothesis is that the growth dysplasia results from the interaction between lion genes and tiger womb enviroment. The tiger produces a hormone that sets the foetal Liger on a pattern of growth that does not end throughout his life.\r\nThe hormonal hypothesis is that the cause of the male Liger’s growth is his sterility †essentially, the male liger remains in the pre-pubertal growth phase. This is not upheld by behavioural evidence †despite being sterile, many male ligers become sexually mature and mate with females. In addition, female ligers also attain great size but are fertile.\r\n'