Siamese Cat Kinked Tail

It was entirely normal for original Siamese cats to have kinked tails. The Siamese cat was referred to as "The Royal Cat of Siam". Mrs Vyvyan who lived in Dover, Kent, UK says that the only purebred Siamese cats in Siam (now Thailand) were at the King's Palace. In other words all the others were not purebred. That makes sense because it was the time of the beginning of the cat fancy and the breeding of purebred cats. Certainly in Siam if a cat was deemed to be purebred is was not assessed as such through cat association records but by observation and/or the cat being confined to a certain area - perhaps the King's Palace.

It is believed, she says, that the original pair that were imported into England came from the Palace and that importation happened with great difficulty because they were rare even in Siam and the king wanted to keep them. Mrs Vyvyan was the person who imported them. She was living in China at the time and the cats reached her in 1886. She brought "the father, mother and a pair of kittens to England". The history of the importation of the Siamese cat is a little muddled so you will see variations on the theme.

She says that, "most of the kittens have a kink in the tail". She goes on to say that the kink varies in its position on the tail; the middle of the tail, close to the body (towards the base of the tail) or towards the tip of the tail forming a "hook".

Mr Harrison Weir, the founder of the cat fancy and the first cat show, says that Mrs Vyvyan's description of the kink tallies with the descriptions of Charles Darwin, the famous naturalist who created the theory of evolution of the species. In his studies and writings he referred to cats with shortened tails.

At page 47 of Mr. Darwin's book, "The Variation of Animals and Plants under Domestication," vol.i, page 47, he writes that throughout the area of the Malayan Archipelago, Siam (Thailand), Pequan (no idea where that is - it's an outdated name) and 'Burmah' (Myanmar) "all the cats have truncated tails about half the proper length, often with a sort of knob at the end".

Darwin also refers to the "Madagascar cat", which he says has a "twisted tail".  This observation is confirmed by another scientist who says that the "Malay cat" has a tail that is half the normal length and contorted into a sort of knot, which cannot be straightened.

Harrison Weir makes the point that the kinked Siamese cat tail is reminiscent of the truncated tails referred to by Darwin. They are both "defects" for want of a better description in a cat's tail. Incidentally Mr Weir also speculates that the Manx cat might have originated in the Malayan short tailed cat.

Clearly in that part of the world, the Far East, a genetic mutation has taken place that was, and probably still is, widespread which affects cats' tails. The genetic mutation that shortens the tail may be linked to the mutation that causes the Siamese cat's tail to kink. I don't know of any science to support that, however.

Breeders in the West, selectively bred out the kinked tail. They did not like it. It did not conform with western notions of beauty. They also modified the appearance of the original Siamese cat to extreme proportions in an attempt to "refine it". I am afraid that they failed in that task as judged by public opinion.

It is interesting to speculate what would have happened if the breeders had decided to keep the kinked tail and made a feature out of it.

Source: there are many sources for this. The main source is Harrison Weir's Our Cats and all about them first published in 1889, now published by Read Country Books.

Siamese Cat Binocular Vision

The Siamese cat is well known for a squint and a kinked tail. Both have been bred out by breeders over the years as they are considered "defects" but they are nonetheless part of this cat breed's heritage. The kinked tail in cat show competition is reason to disqualify the cat as I recall.

There are colorful legends regarding the squint that are usually about Siamese cats who defended temples and valuables. The task was arduous and it caused the cats to develop a squint!

The question on some people's minds is, "does the Siamese cat squint affect normal vision and particularly binocular vision?" Let's first say that it isn't just Siamese cats that have squints but they have a genetic predisposition to acquiring the squint. The cat below is not a Siamese but has a clear squint. Perhaps she is a Siamese mix (lynx point)

Not Siamese but clear squint - Photo by fazen (Flickr)

Cats have two eyes to allow them to judge distance and depth. Two eyes give animals a form of three dimensional vision. This is important to cats in making judgements on tracking objects, jumping and hunting etc.

It transpires that the squint is apparently a compensation for defective wiring of the nerves that go from the eyes to the brain. In normal cats half the optical nerves cross over to the side of the brain opposite to the position of the eye. This provides binocular vision.

In Siamese cats the nerve fibres that were not meant to cross over, do in fact cross over. This causes "the faulty positioning of the retinal map on the tectum". The tectum is a region of the brain, specifically the dorsal part of the mesencephalon (midbrain). The squint cancels out the effects of the faulty positioning on the tectum by "altering the positioning of the retina".

So there you have it. The squint develops over the first six to eight weeks of the kitten's life to make this compensation.

Siamese cat binocular vision is maintained by the famous Siamese cat squint. That's how nature has compensated for a genetically inherited neurological defect. Incidentally, the Siamese and Persian cats have the most genetically inherited diseases and are two of the most long standing purebred cats.

The references are from the New Scientist Aug 17, 1972. Thanks to Google Books.

Siamese Cat Kinked Tail

The Siamese cat was known for three things in the 1800s in England, (1) the pointing - the dark extremities (b) its rarity (it was considered exotic) and (c) its kinked tail.

"..........showing in greater or less degree a decided kink or bend near the tip" (The 1911 Encyclopedia Britannica).

The Siamese cat is also known to have had (and probably still does in Asia), a shortened tail due to a recessive gene (br) mutation. The Mekong Bobtail is a bobtailed Siamese cat!

In other Siamese you might see a kinked tail or swollen tail (due to fused vertebrae).  The shortened tail and the kinked Siamese tail may be different expressions of the same gene.

Selective cat breeding has religiously bred out what is considered a deformity in the kinked tail. It is now outlawed by the cat fancy whereas once it was considered interesting.

Apparently the kinked tail in Siamese cats still pops up in breeder litters. It would seem that getting rid of the Siamese kinked tail from breeding lines is proving difficult.

Not a Siamese cat but Siamese cats are black with the Siamese gene which creates
the pointing. This picture shows the kinked tail very clearly.

See much more on this subject from a book published in 1889 and written by the founder of the cat fancy, Harrison Weir.