The normal tail has 21 - 23 vertebrae on average with the normal range being 18 - 28 vertebrae. It is on average 25 cm (10 inches) long, but can range from 20 cm (8 inches) to 30 cm (12 inches) with a few exceptional specimens having 35 cm (14 inch) tails
There are various mutations affecting the tail and in 1940 American zoologist Ida Mellen wrote of oddities in cats' tails including kinked, bobbed, curled and even double tails. Curly tailed cats were known in China in the 12th Century (probably bobtails) and ringtail cats were known in the USA sometime prior to 1940. In 1868, Darwin wrote in The Variation of Animals and Plants Under Domestication "Thropughout an immense area, namely the Malayan archipelago, Siam, Pegu, and Burmah, all the cats have truncated tails about half the proper length, often with a sort of knot at the end."
Tailless and cats have occurred periodically through random mutation. They have been reported in Bosnia, Burma, China, Crimea, Java, Malaya, Denmark, Nova Scotia and Thailand though some of these will have been bobtails. Bobtail cats occur throughout Asia and into Russia, with more recent mutations occurring in the USA. In a 1949 study, Searle found no kinked tails in London cats. He studied Singapore's cats in 1959 and eventually concluded that stubby-tailed cats were common in Singapore, but in general was rare in Europe except for the Manx breed where the tail was often completely absent. The Manx and the Asian bobtails are due to different mutations. Research indicates that the “tailless gene” has 4 alleles i.e. there are four different versions of the same gene. The Manx breed is based on one of those mutations, and that mutation can have side effects such as spina bifida. The PixieBob is based on a different mutation of the same gene; that mutation has a different appearance from the Manx mutation. The American Bobtail, which occurred spontaneously in a different geographic area, may be based on the same, or a different mutation of the same gene. The Kurilian Bobtail is due to an incomplete dominant gene. However, the similarly named Karelian’s bobbed tail is due to a recessive gene, as is the Japanese Bobtail.
Tailless cats occur spontaneously though random mutation. In 1809, a female cat in Edinburgh produced several litters of tailless kittens. The Edinburgh tailless cat line appears to have been lost. In the 1990s a tailless dwarf female cat occurred in Essex, England. It had poor bowel control as a result of lacking either the nerves which prompt defecation or possibly the muscles at the base of the tail which help empty the rectum.
The most famous tailless variety is the Manx. In 1837 a race of tailless cats was reported in Pendarvis, Cornwall and also in a village in Dorset. The Dorset cats were said to be from the same stock as the Cornwall cats. In 1909, this tailless variety was known variously as the Cornwall cat or Manx cat. This trait was apparently lost in Cornwall and Dorset but persisted on the Isle of Man due to genetic isolation from other cat populations. This allowed the gene for taillessness to become widespread on the island despite detrimental side-effects. In the mid-1800s, the superficial similarity between the Manx cat and the rabbit inspired writer Joseph Train of Castle Douglas, Galloway to include a description of it in his book "An Historical and Statistical Account of the Isle of Man" (1845). He stated that Manx cats were truly the product of matings between female cats and buck rabbits. This is now known to be a genetically impossible.
The Cymric is a semi-longhaired Manx, named after the Welsh name for Wales (Cymru) although it was developed in the US. It is known elsewhere as the Manx Longhair. The recessive gene for longhair has always been present and was regarded as undesirable until Canadian breeders in the 1960s decided to develop it as a breed in its own right. In the 1880s, some Manx had been crossed with Persians (mostly through curiosity) and this would also have contributed the recessive gene for long hair.
There is also a line of tailless cats in Denmark; these are believed to be Manx in origin, probably from ship's cats which jumped ship. The only places tailless cats are actually common is on the Isle of Man, in the Crimea and a self-perpetuating population of Manx-type cats on islands off at Cape Breton, Nova Scotia. Although tailless cats that occur in the random-bred population are often called Manxes or Manx-types, a more appropriate term is "Domestic Tailess" since they may not have any true Manx ancestry.
The Cape Breton Bobtail is a local strain of Manx-type cats found on islands at the south end of Cape Breton, Nova Scotia. As with the Manx, Japanese Bobtail and Kuril Bobtail, the closed gene pool of an island location has given rise to a self-perpetuating variety. The term "bobtail" is a misnomer since the cats do not have pom-pom tails. Fully tailed Cape Breton cats can apparently produce bobtailed kittens, indicating a recessive gene though this is not confirmed (the classic Manx mutation is dominant). The Cape Breton Bobtails are similar to Manx cats, either a recent mutation or having Manx ancestry from cats imported onto the island (in which case the the "fully-tailed" cats are actually Manx-type "longies"). They are not completely tailless nor is the tail kinked into a pom-pom. It is a rabbit-like scut which sticks upwards as seen in rumpy-riser or stumpy Manx cats. The conformation is Manx-like with regard to the longer hind-legs and the coat is soft and plush. The overall body shape and head shape are described as being less cobby and rounded than the Manx and with a more refined elegance like that of the Japanese Bobtail. So far, no-one has selectively bred this strain of bobtails and the island's cat population fluctuates. As long as there are plenty of cats on the island, the recessive gene should remain in the population, but if the strain is to be bred, conserved or studied (or even used to expand existing gene pools) it would be wise to do it sooner rather than later.
In September 2002, I had an email from Sandra Norman of "Amazing Grace" cattery (Desert Lynx and Savannahs). She had read of the "Minx". Minx is not a breed, but is a term often used to describe a miniature Manx-type cat and sometimes confused with Manx. Sandra sent a photo of her miniature tailless cat "Cupcake". Cupcake is a perfectly formed miniature, not a dwarf. She produced two litters of kittens before being spayed. Unfortunately she has poor bathroom habits - a defect sometimes associated with the lack of tail: the muscles at the base of the tail are also involved in controlling the rectum.
In 2008, the Kernow was suggested as a truly Cornish cat combining two mutations indigenous to Cornwall. Tailless cats occurred in Pendarvis, Cornwall in 1837 and the variety was known as the Cornwall Cat until 1909 when tailless cats all became known as the Manx. The Cornish Rex occurred in Bodmin, Cornwall in 1950. The Kernow would combine both of these "Cornish" traits and would essentially be a tailless British-style Cornish Rex in both shorthair and longhair versions. The Oriental conformation of the American Cornish Rex and the Siamese/Burmese colours or patterns are not allowed. Blue-eyed or odd-eyed whites/bicolours are not allowed because of deafness. Kernow is the Cornish word for Cornwall.
EARLY HISTORY OF THE MANX
There are numerous legends surrounding the Manx. The most widespread is that it is a cross between a cat and a rabbit. According to another, the Manx was tardy in boarding the Ark and Noah slammed the Ark doors, severing the dawdling cat's tail. In yet another, ancient warriors cut off the tail to use it decoratively and mother cats, to save their kittens from this treatment, bit off the tails of their kittens at birth. According to Rose Tenent in her book "Pedigree Cats" (1955): "Another view put forward is that the Phoenicians may have brought tailless cats westward from Japan in the grain-boats to keep down the rats and mice. As we have evidence of tailless cats in Japan, this is certainly a more probable theory, except that there are absolutely no traces of the. migrations over those ancient trade-routes of the world which they would have passed." The Manx was first noted in print in 1810 in a reference to tailless cats from the Isle of Man owned by the great English painter, Turner. In 1834, the Magazine of Natural History noted that the author had seen several tailless cats belonging to peasants living among the mountains between Ramsey and Peel; he was told they had come from a wreck of a vessel from Prussia or some Baltic port many years previously. The cats were also known as "Stubbin", an English word; according to some historians this suggests the tailless cats arrived on the Island some time after 1750, since up to 1750 the main language was Manx. Cregeen's Manx Dictionary of 1835 defines "Stubbin" as "a cat without a tail".
In Mrs Jane Hellman's paper researching the history of Manx cats, the author noted that there had been stories of tailless cats in the Crimea, but Dr Kerruish (who established a famous Manx cattery on the Isle of Man) believed that the mutation in the domestic shorthair that produced the tailless cat occurred circa 1730, basing this belief on the fact that the Manx language fell into disuse at that time and that there was no Manx word for the tailless cats (if there was no need to have a word for tailless cats, they must not have existed).
In his 1845, "An Historical and Statistical Account of the Isle of Man," Joseph Train wrote "According, to my friend, Mr. Forbes, the only quadruped peculiar to the Island, of which it can boast, is the tail-less cat, called in Manks, "Stubbin," and in English, "a Rumpy." This is, he thinks, an accidental variety of the common species felis catus, frequently showing, no traces of caudal vertebrae, and others merely a rudimental substitute for it. There is a tradition still current in the Is land, that the first rumpy cat seen there was cast on shore from a foreign vessel that was wrecked on the rocks at Spanish Head, but at what period no one pretends to say. A modern author speaks with more certainty by affirming that the rumpy is the genuine aboriginal cat of the Island. As a mouser, the rumpy is preferred to all others of its kind. Formerly when cats were scarce in Europe, the rumpy would have brought a high price. In Wales the value of a cat was fixed by law, and the same regulation extended to the Isle of Man, when-under the rule of the Cambrian Princes. The Manks rumpy resembles some what in appearance the cats said by Sir Stamford Raffles to be peculiar to the Malayan Archipelago. Of late years, many rumpies have been carried out of the Island as curiosities by visitors. I have had one in my possession for upwards of four years-a circumstance which has afforded me an opportunity of observing the habits of the animal.'
My observations on the structure and habits of the specimen in my possession, leave little doubt on my mind of its being a mule, or crosses between the female cat and the buck rabbit. In August, 1837, I procured a female rumpy kitten, direct from the Island. Both in its appearance and habits it differs much from the common house cat: the head is smaller in proportion, and the body is short ; a fud or brush like that of a rabbit, about an inch in length, extending from the lower vertebra, is the only indication it has of a tail. The hind legs are considerably longer than those of the common cat, and, in comparison with the fore legs, bear a marked similarity in proportion to those of the rabbit. Like this animal too, when about to fight, it springs from the ground and strikes with its fore and hind feet at the same time. The common cat strikes only with its fore paws, standing on its hind legs. The rumpy discharges its urine in a standing posture, like'a rabbit, and can be carried by the ears apparently without pain. Like every species of the felince, it is carniverous and fond of fish, and is an implacable enemy to rats and mice. My little oddity was six months old before it saw a mouse, but when a dead one was exhibited, it instantly displayed all the characteristics of a practised mouser. It has never had any offspring, although the common cat propagates its species when about twelve months' old. Indeed, on this subject, although I have made many inquiries, I have not been able to establish a single instance in which a female rumpy was known to produce young. My opinion, as to the origin of the rumpy, has been strengthened by a coincident circumstance connected with this district. A few years ago, John Cunningham, Esq., of Hensol, in the stewartry of Kirkcudbright, stocked a piece of waste land on his estate with rabbits, which multiplied rapidly. In the immediate neighourhood of this warren rumpy cats are now plentiful, although previously altogether unknown in the locality. Not a doubt seems to exist as to the nature of their origin. I am afraid the known facilities which exist in the Isle of Man, for giving effect to this opinion as to the origin of the rumpy, may go far to dissipate the cherished belief of the Islanders, in its being a distinct genus. At the same time I am far from wishing my statements to be understood as settling the question. My opportunities of observation have induced this general opinion of their origin, but, as it is possible many local objections may be taken to its reception, I would willingly avail myself of any authenticated communication on this head, before the final publication of my work. I have no wish, apart from the discovery of truth, to deprive the Island of this, or any of its peculiarities.'
According to the “Illustrated Natural History” by the Rev JG Wood (1853, 1874): The Manx Cat is a curious variety, on account of the entire absence of tail, the place of which member is only indicated by a rather wide protuberance. This want of the usual caudal appendage is most conspicuous when the animal, after the manner of domestic Cats, clambers on the tops of houses, and walks along the parapets. How this singular variation of form came to be perpetuated is extremely doubtful, and at present is an enigma to which a correct answer has yet to be given. It is by no means a pretty animal, for it has an unpleasant weird-like aspect about it, and by reason of its tailless condition is wanting in that undulating grace of movement which is so fascinating in the feline race. A black Manx Cat, with its glaring eyes and its stump of a tail, is a most unearthly looking beast, which would find a more appropriate resting place at Kirk Alloway or the Blocksberg, than at the fireside of a respectable household. Or it might fitly be the quadrupedal form in which the ancient sorcerers were wont to clothe themselves on their nocturnal excursions.
Far from losing their tails to the Ark's doors or to warriors or being a mule (hybrid) of cat and rabbit, the trait is due to a gene mutation. In his book "Variation of Animals and Plants Under Domestication" Charles Darwin referred to the Manx "The Manx cat is tailless and has long hind legs; Dr. Wilson crossed a male Manx with common cats, and, out of twenty-three kittens, seventeen were destitute of tails; but when the female Manx was crossed by common male cats all the kittens had tails, though they were generally short and imperfect.".
Harrison Weir, founding father of the cat fancy and organiser of the first formal cat show (also writer of the first standards for pedigree cats), wrote about the Manx in "Our Cats" in 1889. He also acknowledged the existence of a breed of tailless cats in Cornwall. Weir wrote that the Manx was well known and by no means uncommon. Wholly tailless cats were preferred and he noted that the hind legs should be thicker and rather longer, particularly in the thighs. He even hinted that it was ungainly in motion: "It runs more like a hare than a cat, the action of the legs being awkward, nor does it seem to turn itself so readily, or with such rapidity and ease."
Weir examined a number of specimens sent for exhibition at the Crystal Palace and other cat shows, and noted that some had very short, thin, twisted tails while others had "a mere excrescence" and yet others had "an appendage more like a knob" These he took to have been fakes (fakery being common at early cat shows) where the cat had been operated upon when young to remove the tail. With little understanding of the genetics of taillessness, he went on to say "But this may not be the case, as Mr. St. George Mivart in his very valuable book on the cat, mentions a case where a female cat had her tail so injured by the passage of a cart-wheel over it, that her master judged it best to have it cut off near the base. Since then she has had two litters of kittens, and in each litter one or more of the kittens had a stump of tail, while their brothers and sisters had tails of the usual length. But were there no Manx cats in the neighbourhood, is a query. This case is analogous to the statement that the short-tailed sheep-dog was produced from parents that had had their tails amputated ; and yet this is now an established breed. Also a small black breed of dogs from the Netherlands, which is now very fashionable. They are called "Chipperkes," and have no tails, at least when exhibited."
The belief that amputation could cause hereditary taillessness was not uncommon. To his credit, Weir was sceptical. A certain Mr. Bartlett had reported to him that, in the Isle of Man, the cats had tails of different lengths, from tailless through to ten inches. Though he had been told that Fox Terrier dogs with docked tails sometimes had short-tailed puppies, he had already noted that sheep - which were also routinely docked - did not have short-tailed or tailless lambs!
Weir wrote that cross-breeding Manx with other cats often resulted in tailless offspring. As proof, he cited the case of Mr. Herbert Young of Harrogate, who owned "a very fine red female long-haired tailless cat, that was bred between the Manx and a Persian". Another case which showed the strong prepotency of the Manx was Mr. Hodgkin of Eridge whose Manx female produced tailless cats when crossed with an ordinary domestic cat, and whose offspring themselves produced some tailless kittens.
In Weir's time, the Japanese Bobtail was not known although the mutation had been described by travellers. With no concrete information to go on, Weir wondered if the Manx was somehow related to those cats since Weir had seen cats with precisely the kinds of tail described in books by Darwin and Mivart. In 'The Variation of Animals and Plants under Domestication", Darwin had written "throughout an immense area, namely, the Malayan Archipelago, Siam, Pequan, and Burmah, all the cats have truncated tails about half the proper length, often with a sort of knob at the end. […] The Madagascar cat is said to have a twisted tail." Mivart had corroborated the statement regarding the Malay cat, of which he said the tail "is only half the ordinary length, and often contorted into a sort of knot, so that it cannot be straightened […] Its contortion is due to deformity of the bones of the tail," and added that there was a tailless breed of cats in the Crimea. There was certainly confusion between the Manx and the Japanese and Malayan bobtails, for in "Our Cats" in 1900, H C Brooke wrote of a "recent farce" when a cat won in succession as a Manx and then as a Japanese cat. Originally, stated to be of Manx parentage, it was later shown as a Japanese because some 'connoisseurs of foreign cats' declared it must be a Jap because it had a kink in its tail!
Not all writers of that era liked the Manx. According to R S Huidekoper in his book, The Cat (1895), "The Manx Cat really can be classed as a monstrosity, having been developed probably by the interbreeding of some freak of nature in the form of a cat which inhabited the Isle of Man at an early period. An ordinary cat can easily be rendered tailless if operated on at a young age [...] especial attention should be paid to see that the absent tail is natural and that there is no scar as evidence of operative interference, or, as such things are called in dog shows, “faking”."
Jean Bungartz described the Manx or Stub-tail cat (Felis maniculata domestica ecaudatus) in his 1896 book "Die Hauskatze, ihre Rassen und Varietäten" (Housecats, Their Races and Varieties) in " Illustriertes Katzenbuch" (An Illustrated Book of Cats). He noted that Cellar described it in a feline supplement of the animal stock exchange. Cellar had described it as coming from Cornwall and the Isle of Man and forming a distinct race. As well as tailless cats, Cellar noted part-tailed cats that presumable took after the father. Bungartz wrote that the missing tail, strong hindquarters and long hindlegs allowed the Manx to make great jumps from branch to branch so it was an excellent tree-cat and a danger to birds.
Frances Simpson, in "The Book of the Cat" (1903) mentioned some of the theories about the breed's origins, including contributions from residents of the Isle of Man, breeders and others.
"A lady friend of mine, who was brought up in the Isle of Man, has told me that she always understood that Manx cats came from a cross with a rabbit, but if this supposition is correct it seems too strange to be true that cats and rabbits should only form matrimonial alliance in the little island off our coast! It would appear more probably, therefore, that a foreign breed of cat was brought to the island, and the following article from the pen of Mr Gambier Bolton gives his ideas on the subject:-
'In the Isle of Man today we find a rock named the Spanish Rock, which stands close into the shore, and tradition states that here one of the vessels of the Spanish Armada went down in the memorable year of 1558, and that among the rescued were some tailless cats which had been procured during one of the vessel's voyages to the Far East. The cats first swam to the rock, and then made their way to the shore at low tide; and from these have sprung all the so-called Manx cats which are now to be found in many parts of Great Britain, Europe, and America. The tale seems a bit 'tall' and yet the writer feels so satisfied of its truth that he would welcome any change in the name of this peculiar variety of the domestic cat to sweep away the idea that they sprang from the Isle of Man originally.
Any traveller in the Far East - Japan, China, Siam, and the Malay region - who is a lover of animals must have noticed how rarely one meets with a really long-tailed cat in these regions, for instead one meets with the kink-tailed (i.e. those with a bend or screw at the tip of the tail), the short kink-tailed (i.e. those with a screw like tail like the bull-dogs), the forked-tailed (i.e. those having tails which start quite straight, but near the tip branch out into two forks) and finally the tailless (or miscalled Manx) cats; and the naturalist Kæmpfer states definitely that the specimens of this breed now so common in parts of Russia all come originally from Japan. Again, anyone who breeds these tailless cats, and keeps the breed quite pure, must have noticed how they differ in appearance and habits from the short-haired cats. They are, and should be, much smaller in size; the coat should be longer and more 'rabbity'; the 'call' is much nearer that of the jungle cat of the East than that of the ordinary cat; and their habits, like those of Siamese cats, are much more dog-like. In all these points they keep closely to what the writer firmly believes to be their original type, the domesticated cats of the Far East. […] Kink-tailed, screw-tailed, fork-tailed and absolutely tailless cats have all be exhibited at British shows of recent years.' "
A letter from an anonymous Isle of Man resident to "Our Cats" (June 30th, 1900) said "When I was a boy there was a kind of tradition that the tailless cat was brought here by the Spanish Armada. We have a headland called 'Spanish Rock' where it has been believed that some tailless cats escaped and took refuge here, and that from such cats all the so-called Manx have been derived. During my life I have frequently met persons who have travelled in Spain, and I think I have always asked from such persons if they had ever met with tailless cats there, but I never met anyone who had seen them. I never heard any other (traditional) origin of the Manx cat alleged. They are very common here, but not so common as cats with tails. Both cats with and cats without tails associate together."
A letter from another Isle of Man resident in the same issue was equally dubious of the shipwrecked cats theory and wrote: "Certainly we have cats with tails - the rumpy being the rare form. Perhaps one in a litter, and one or two of them with half tails. As to what they are supposed to be, I have of course heard the Spanish Armada story. My own belief is that they have originated in a sport [a mutation], e.g. as we find in dogs and fowls, and have been perpetuated as curiosities, and in modern times on account of their commercial value. […] The height of the hind legs is perhaps more apparent than real, caused by the abrupt ending, without the falling tail as in ordinary cats. Professor Owen made a preparation, which may be seen at the British Museum, showing the bones (if any) of the tail. I think in a perfect specimen there should be no bones. Of course, there are all degrees of stumps."
In his contribution to "The Book of the Cat", renowned breeder (of several breeds, including the Manx) and cat fancier, Mr H C Brooke gave credence to a theory of inheritance which stated that amputation of an animal's tail would cause it to have tailless offspring: "What is the origin of the Manx? That is a question which in all probability will never be answered. The theory that it originated from a cat (or cats) having lost its tail by accident I do not consider worth a moment's considerations. Such a cat might well have tailless progeny, but that would have nothing to do with the abnormal length of the hind legs, which in good specimens is patent to the most superficial observer, and which makes the gambols of a couple of Manx a comical sight calculated to excite laughter in the most mournfully disposed person. Quaint is the old versified explanation, which I remember hearing some years ago. It ran, if I remember rightly, somewhat like this:-
Noah, sailing o'er the seas,
Ran high and dry on Ararat.
His dog then made a spring, and took
The tail from off a pussy cat.
Puss through the window quick did fly,
And bravely through the waters swam,
Nor ever stopped, till, high and dry,
She landed on the Isle of Man.
Thus tailless puss earned Mona's thanks,
And ever after was called Manx.
The most feasible explanation, in my opinion, though of course it can be but a theory, is that these cats were originally imported from the East. Asiatic cats of domestic varieties show remarkable variety in the shape of their tails, as witness the kinks often found in the tail of the Siamese cat, and the knot tails of other varieties."
According to Katharine L Simms in "They Walked Beside Me" (1954): "An old Manx newspaper of 1808 described Manx cats as 'Rumpy cats'. In build he is higher in the rump than the ordinary cat, for his hind legs are longer than his forelegs. For this reason the Manx is sometimes called the Kangaroo cat, for he has the hopping gait of a kangaroo and a rabbit. This started the absurd story that he is the result of mating between a domestic cat and a rabbit. Such a cross between two entirely different species is, of course, impossible. He has, however, yet another likeness to the rabbit in the quality of his fur; a double coat, fine and loose above, and a very thick soft undercoat ....Bob-tailed cats have long been known in the Far East. Crosbie Garstin in his 'Dragon and Lotus' about the East says, 'at the ferry on piles - each dwelling had its chocolate babies - and its bob-tailed cat ...' Or the Manx of today may be a descendent of the Kimono cats of Japan who have very short triangular tails. It seems no-one knows whence the Manx came, or for how long he has been resident on the island in the Irish Sea" It was common to confuse the two types at the time. Ms Simms believed Manx cats arrived on the island from Annam, Burma, Siam, Malaya, or the East Indies, brought by traders in the 18th century."
In his book “Just Cats” (1957), French cat-fancier Fernand Mery wrote “Then there is that other scientific fantasy according to which the Manx cat is descended from an astounding match between a female cat and a rabbit.”
Brian Vesey-Fitzgerald "Cats" (1958) noted that Darwin's observation of stump-tailed and tailless cats in Malaya caused some writers to state that the common cat of Malaya was tailless. He adds that this was not the case in the 1950s and he doubted it ever was the case. He could find tailless cats particularly mentioned in the works of any of the early explorers or in the writings of the Victorian missionaries (missionaries gave very exact descriptions of their surroundings). While acknowledging that tailless cats occurred in Malaya he considered it ridiculous to suggest that the Manx derives from Malayan cats. Tailless cats also occurred in China, "for which we have the authority of both Père Huc (who knew a great deal about cats) and Pére David for this. But neither of these reverend gentlemen ever suggested that these tailless cats were the common cats of any particular region of China: they were noted not because they were common, but because theywere uncommon." He added, flippantly, that nobody had suggested that Manx derived from those tailless Chinese cats! He also noted tailless cats existing in Russia and being particularly common in the Crimea as they were mentioned in the writings of both English and French soldiers of the Crimean war. Vesy-Fitzgerald's thoughts were that tailless cats might possibly have spread along the Mediterranean in merchant ships trading out of the Black Sea, and also that they might have been carried in Viking longships from northern Russia.
At a Feline Fantasy staged by the Silvergate Cat Club of San Diego, USA. in 1952, a "Sianx" cat was exhibited. This was a Siamese-Manx cross with Seal Point colour and type, sans tail. However, the Western province Cat Club of Cape Town claimed precedence in Sia-Manx breeding. The late Father Fowler's Sia-Manx was exhibited at their show during 1952, some months before the cat at the San Diego show, and resembled a Siamese Seal Point with definitely high hind quarters and complete absence of tail. He was described as a very charming person by Miss P. Ashby-Spilhaus, the Registrar of the South African Cat Union.
Manx taillessness is varied in expression, ranging from the highly desirable rumpy (no tailed) which may have a dimple at the base of the spine, the rumpy-riser (one or two vertebrae), the stumpy (a bit longer and often knobbly) and the longy (full-tailed though this is often shorter than that of a non-Manx). The longy is the rarest of these. In 1902, six types of Manx were described, these varied as to the length of the back, the slant of the back and the tail type (rumpy or stumpy only).
Weir had already reported that Manx cats, when bred to Persians and other, produced Manx kittens. One of the earliest studies into Manx inheritance appeared in "Our Cats" in March 1900; the article being a translation of an article in the German paper "Mutter Erde". Although it knew nothing of the actual genetics, it was clear that Manx cats produced both Manx and tailed offspring.
"The Progeny of a Tailless Cat of the Isle of Man. A cat brought from the Idle of Man (felis catus anura) to S. Germaine en Laye, of which the pedigree is unknown, was mated with ordinary long-tailed cats, and among twenty-four kittens, the four following kinds appeared:
I - Kittens with ordinary long tails.
II - Kittens with short and stump tails.
III - Kittens without tails, like the mother.
IV - Kittens without the least sign of a tail.
The comparison between the influence of the sire and that of the dam on the young is interesting:-
1 litter - 1 kitten like the mother.
2 litter - 6 kittens, 5 like the mother, 1 like the father.
3 litter - 5 kittens, 3 like the mother, 2 like the father.
4 litter - 3 kittens, 1 like the mother, 2 like the father.
5 litter - 4 kittens, 1 like the mother, 3 like the father.
6 litter - 5 kittens, 3 like the mother, 2 like the father.
It will be seen that the influence of the mother predominates."
According to Albert C Jude (geneticist) writing in 1955 ("Cat Genetics"), the tailless or almost tailless Manx were the homozygotes while the tailed Manx were heterozygous. The true "lethal" nature of the gene in homozygotes was not then known. "Mendelism" (genetics) was then a new discipline and traits tended to be viewed in terms of simple dominant/recessive terms. The lethal nature of homozygous Manx was not then understood.
The genetics of the Manx is interesting. The trait is genetically an incomplete dominant and is classed as semi-lethal or sub-lethal i.e. it is not lethal in heterozygotes (cats which inherit one copy of the gene for taillessness) but it is fully lethal in homozygotes (those which inherit two copies of the gene). The various types of tail and the degree to which other defects are present indicate that it is an incomplete dominant and that other genes interact, hence the trait is variable. All surviving Manx cats carry the gene for a full tail. Kittens homozygous for the Manx trait are either reabsorbed during pregnancy or are stillborn. This means that Manx litters average 25% fewer kittens than non-Manx litters. It also means that there are no pure-breeding Manx. Manx litters contain an abnormally high proportion of female kittens, suggesting that male kittens are less likely to survive. Stillborn Manx kittens and cats which die young reveal a greater number of skeletal and organ abnormalities than those which survive beyond 12 months. Autopsy has found spina bifida in a number of these and Manx cats have been used as laboratory models for studies into neural tube defects.
The influence of the Manx gene(s) affects the entire vertebral column, not just the tail (though some breeders dispute this). The vertebrae at the top end of the spine (the front end of the cat) tend to be shorter than usual. Those at the lower end (back end of the cat) are fewer in number and may be fused together leading to reduced mobility. The pelvic and sacral bones maybe malformed and/or fused. The pelvic opening may be so narrow that the cat cannot defecate easily. To prevent chronic constipation, surgical correction is needed e.g. to insert wedges into the pelvis to enlarge the opening. The vertebral column contains the spinal cord (the main highway of the nervous system). One side effected linked to the gene for taillessness is that the spinal cord may terminate somewhere along the spine and not reach the end of it. This affects certain organs, can lead to lack of bladder/bowel control and affect the control of the hind legs. Homozygous Manx kitten foetuses have been detected as being abnormal at 5 weeks gestation, are undersized and have grossly malformed central nervous systems.
The problems of breeding Manx had been noted in the 1950s. In her book "Pedigree Cats" (1955), Rose Tenent included the observations of Mr NS Twining, Hon. Secretary of the Isle of Man Manx Cat Association in the early 1950s. Twining had observed may matings - both deliberate and accidental - and had found that when two good rumpies were mated, the progeny was often poor. A rumpy queen of complete Manx ancestry was always mated to good rumpy toms, yet only on one occasion did she produce a good Manx kitten, and it only lived for three days (Twining referred to tailled Manx as "tailled cats of Manx ancestry rather than true Manx cats).
Breeders are careful to breed only from cats without obvious spinal defects although vets have to surgically correct some problems. Reputable breeders have worked hard to eradicate these faults or to reduce the incidence of abnormalities. The number of defects has dropped considerably due to selective breeding, but it is dangerous to deny (as some Manx breeders do) the existence of such abnormalities since there is a wealth of scientific documentation. The existence of abnormalities was recognised by the GCCF in Britain and in 1968, the GCCF dropped mention of the "hoppity gait" from the Manx standard; the gait once considered proper to the breed being caused by a defect that makes it difficult for the cat to move its hind legs independently. It is also considered inadvisable to breed tailless cats together as there is a greater risk of abnormal foetuses or small litter sizes due to resorption of foetuses.
In the 1970s and 1980s there was much debate over whether the Manx gene caused other abnormalities as claimed by some researchers (Roy Robinson's "Genetics for Cat Breeders", still the most important text on the subject, was first published in 1971 and would have documented the Manx effect). In "The British, European and American Shorthair Cat" in 1981, Phyllis Lauder wrote that FIFE (Federation Internationale Feline d’Europe), in Sweden, had banned Manx, saying it was wrong to perpetuate a defective breed, "the taillessness being a distressing congenital defect bred purely for showing which means misery and death for many of the cats"’. (This parallels a recent European directive that bans defective breeds). Manx expert Jane Hellman had written that the "hoppity", rabbit-like gait once valued in Manx, was due to an undesirable defect; however their long hind legs meant that Manx cats could run like hares. Lauder noted that rumpy-to-rumpy matings for more than one generation supposedly resulted in infertility and fading kittens, but Hellman claimed this to be untrue if the parents were healthy. Lauder summarised, unfortunately with a red herring, that Manx taillessness could not be a defect since humans were also tailless!
Hellman's paper claimed it was absurd to suggest that one gene was responsible for lack of tail, shortness of back, length of hind legs and softness of the double coat in Manx cats. Lauder wrote: "This of course cannot be seriously entertained. Pairs of genes govern all the characters in an organism, and every gene is affected by the action of every other gene; characters may be modified by such action, but it can never be maintained that the same allelomorph is responsible for - as an example - length of hind legs AND softness of coat." Though the long hind legs/ soft coat example is a poor one, it turns out that one gene can have multiple effects as a gene encodes for a protein which can be used in different parts of the organism and can influence multiple traits. Lauder added that the Si-Manx bred in Australia would demonstrate that there was no lethal factor and claimed " it must be frustrating for their breeders that ‘To investigate the mechanics of Manx inheritance the scientists have generally used abnormal cats in their experiments. Through this they produced more deformed cats’. Common sense suggests that this is like arranging a marriage between two deaf-mutes and then claiming that mankind suffers from a congenital defect."
Had the mutation occurred in recent times, many cat fancies would have refused to recognise it because of these defects and problems in the same way that those are currently refusing to recognise Scottish Folds, Munchkins or polydactyl cats (polydactyly being non-detrimental and having existed for as long as, or longer than, the Manx). Because the mutation is associated with detrimental side-effects, the cross-breeding of Manx to other breeds to create tailless varieties is discouraged. There are several informal Manx hybrids such as the Manxkin (a Munchkin/Manx cross with short legs) and Mynx (Manx/Sphynx hybrid i.e. hairless Manx) which are not encouraged. The Manxamese or Si-Manx is a colourpoint version of the Manx. There are (or were) plans to introduce Manxes into the Poodle Cat breeding program to create tailless, fold-eared, curly-furred cats. In Australia, a wandering Siamese stud and a Manx female were responsible for the arrival of a ‘Si-Manx’. Phyllis Lauder (1981) considered this as not particularly desirable since standards did not permit the look. Lauder also wrote of news from Australia of regarding the crossing of Manx with Scottish Folds (the latter not yet recognised and its skeletal problems not fully understood). Lauder wrote that the idea was born of a desire to meddle since a Manx/Fold cross would not only produce a freakish-looking cat, it would be a tragedy for the cats - the two breeds had enough to contend with in refuting charges of deformity.
"The Manx gene’s effect often fuses vertebrae and the pelvis, and sometimes varying degrees of spina bifida are seen. Only the fact that the Manx is a historic breed stops us being as critical of this dangerous gene as of other more recent selected abnormalities." (CATS - The Rise of the Cat, Roger Tabor, 1991)