The two reasons why domestic cats are selectively bred, primarily by cat breeders, is to create cats with a certain appearance and secondarily cats with a certain character. Selective breeding is the opposite to natural selection. Natural selection refers to the evolution of the species as espoused by Charles Darwin in his book On the Origin of the Species.
Selective breeding is artificial selection as opposed to natural selection for the fittest (Darwin’s theory of evolution). Selective breeding does not necessarily produce the fittest. It’s objective is to produce the prettiest.
It is only over the past one hundred and fifty years or so that selective breeding has been taking place formally. Before that cats were random bred or they mated through natural selection. There was no human intervention, or very little.
Perhaps the first examples of selective breeding occurred when it is believed that people chose a mutated tabby cat with a blotched pattern rather than the striped pattern to breed cats informally. That would have been well before the cat fancy and cat associations existed. This example might have been extended to other coat types which emerged during the ten thousand years of domestication of the cat.
The original coat type is the striped tabby because that is the coat of the domestic cat’s wild cat ancestor, although it is a more dilute version.
For many several thousands of years the only domestic cat coat type would have been tabby. Then through natural selection other coat types emerged. The size of the cat would vary slightly from region to region because in hot climates cats tend to be smaller whereas in colder climates they are bigger because it aids in survival.
As the domestic cat and semi-domestic cat (community cat) population increased they lived nearer together around food sources which resulted through natural selection in the cats being better able to tolerate small home ranges.
So against this backdrop, the first serious examples of selective breeding would have taken place in the late 1800s sometime before the first cat shows in America and England. In England the first cat show took place on July 13, 1871 at Crystal Palace and in America the first cat show took place at Madison Square Garden in New York City in 1895.
The show cats there would have been early versions of selectively bred purebred cats. A lot of water has passed under the bridge since then and in typical human fashion breeders have pushed the envelope with certain breeds beyond what might be accepted as the proper limit to create extreme bred cats such as the flat-faced Persian, the modern version of the Siamese with an elongated face and body, and the heavy and large Maine Coon with strong muzzles being the latest version of extreme breeding.
To return to the first sentence: the two reasons why cats, and we are only concerned with domestic cats, are selectively bred is because breeders want to make sure that their cats comply with the breed standard as set down by the cat associations and to make sure that their breed is distinguishable in terms of appearance and sometimes in character from other breeds and random bread cats. In doing this they win shows and also ensure that their cats are more marketable.
The cat breeds are in a crowded marketplace and it is quite difficult to ensure that a cat breed is clearly distinguishable from another (e.g. old style Siamese versus contemporary Siamese). On occasions this objective has been aided by genetic mutations which have taken place spontaneously and randomly outside of the cat breeding fraternity but a breeder has picked up on it and created a new cat breed from this mutation. A good example is the hairless cat breeds such as the Sphynx and the Russian version the Don Sphynx.
Selective breeding incorporates inbreeding. The two go together like apple pie and custard. With hopefully reasonable inbreeding cat breeders are able to fix the appearance and sometimes character traits that they want. They select and work with a limited number of cats and then breed them together such as a mother mating with her offspring. This creates a breeding line, the outcome of which is high quality cats of a certain breed in line with the breed standard.
The breed standard sets out briefly whether breeders can outcrossed their cats to either random bred cats or cat another breed, The purpose? To maintain health because inbreeding can result in inbreeding depression which essentially means that the cat has a weakened immune system and suffers from general ill health with a shortened lifespan.Click here for inbreeding depression.
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