You don’t need to know genetics to breed animals. Trial-and-error works quite well, as early hunter-gatherers learned when they switched over to agriculture shortly after the last ice age ended.
In addition to bringing into being what some experts call “the walking larder”–cows, chickens, and other livestock–the very first farmers also domesticated dogs and horses. And down through the millennia, people changed domesticated animals to suit themselves.
- We trained horses not to flee the chaos and noise of a battlefield. Indeed, we somehow developed chargers who would run at full speed into a gunfight or cannon fire.
- We turned the gray wolf into a dachshund, among other breeds. But the wolf nature is still present. The “weiner dog” is a dwarf canine developed to hunt badgers and wounded wild boars: let’s give it some respect, people!
The cat fancy, with its accompanying establishment of various breeds, has only been around for 150 years or so. There hasn’t been enough time yet to make such drastic changes as those shown in other domesticated animals,
Too, the animal welfare movement has grown up alongside the cat fancy. This, together with the powerful tools that modern genetics provides, forces cat breeders to face ethical questions that never troubled the first dog breeders.
Let’s use the Manx fancy-cat as an illustration.
Tailless cats and cats with deformed tails lived on the Isle of Man for centuries before loving owners exhibited them in the first cat shows and Harrison Weir (the “father of the cat fancy”) devoted a whole chapter to them in his 1889 book Our Cats and All About Them.
Weir noted that the Manx:
. . . 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 . . .
This “hoppity” Manx gait used to be part of the breed standard until cat fanciers realized it wasn’t a cute effect of the cat’s extra-long hind legs. Rather, it was a symptom of a serious medical condition that is now called Manx syndrome.
The gene mutation that affects this breed’s tail can sometimes also cause horrible vertebral defects, spinal cord abnormalities, and neurological problems. It will even kill fetuses in certain circumstances.
Manx breeders can and do counter these problems in a variety of ways–chiefly by including some cats with normal tails in the line and, for genetic reasons, never mating together two tailless cats.
It’s not just the Manx, either. A few other fancy breeds, like the Scottish Fold, also have medical syndromes named after them. The same cartilage mutation that makes Maru and other droopy-eared Folds so adorable can also cause skeletal problems.
Is it right to build a breed on genetic disorders? It’s easy to say no, but that’s exactly what we did with the dachshund. It’s a dwarf, but people encouraged this, despite the suffering of a lot of individual animals as the breed developed, because nobles needed a badger dog (and there was no concept of animal welfare back then).
Today’s dachshunds are well established and popular, and most people involved in their care recognize and work around the inevitable health problems.
But mention a minature cat breed, and you might find yourself hip deep in a controversy producing more heat than light.
In the fancy, cat registries vary in their positions. The UK’s Governing Council of the Cat Fancy (GCCF), for instance, recognizes the Manx because the breed goes back centuries. Also, random-bred cats on the Isle of Man that have tail deformities still do quite well, even when feral. However, GCCF does not recognize the Scottish Fold because of animal welfare concerns.
Some of the other major registries find this breed acceptable, as long as a few British or American Shorthairs and some UK moggies are brought into a Fold line to widen the gene pool. This reduces the likelihood of severe bone and joint problems from the cartilage mutation that is needed to meet the breed standard for ear droopiness.
There is no solid moral guidance here. It’s a matter of what a cat breeder is comfortable with. And again, this is a modern problem that the pioneers who first domesticated animals didn’t have to deal with.
Features that distinguish a breed often happen through mutations, which are rare events. Since there aren’t many animals with the desired feature to begin with, breeders must mate offspring back to their parents to establish a breed.
It’s an issue today in the cat fancy, and not just a moral one. To produce healthy cats, good breeders limit inbreeding by using as many different kitties as possible and those that are as distantly related as possible. This, as well as outcrossing (like the British or American Shorthairs used in Scottish Fold breeding), increases genetic diversity.
Still, intensive selective breeding and inbreeding over the years have concentrated some harmful or potentially harmful genes in some breeds. DNA testing helps a lot in avoiding problems, but in some cases, like the very flat face some fanciers prefer in a Persian cat, it is, once more, a matter of what people are comfortable with.
Like it or not, we do have the tools to mold cats and other living beings in almost any way imaginable. Humanity has always had some capability in this direction. Until very recently, practicality was the only measure of whether the end result justified the means.
Now we must take the animal’s welfare into account, too. That is excellent, but it is also a terrible challenge. We may have some of the tools of a god, but we lack a god’s omniscience and therefore cannot wield those tools very well just yet.
Featured image: Ilyesutti, at Pixabay. Public domain.
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