"Nice head, pity the brain doesn't fit in" was the captive caption of a two-page article by Lucas Brouwers, science journalist for the Dutch top-notch newspaper NRC (7 January 2012, Weekend Science Annex). It describes the excessive failures of professional dog breeders to come up with healthy strains, "races", of dogs.
Brouwers extensively shows that dog breeders are unable to breed fit dogs because they aim at peculiar traits as coveted by the public at large. They choose very small or extremely large characteristics, like length of limbs, muzzle, ears, eyes and body. Hairy coat, aggressive behaviour, general cuteness are all bred to extremes. For some reason dogs are much better to maltreat than cats are.
All these traits are related to something called a 'race', a non-biological distinction of animals and that is less than a subspecies. Animals (and men) that belong to a different race are supposed to be able to interbreed fully. Remember that for the remainder of this blog.
The (in)famous Charles Darwin published "The variation of animals and plants under domestication" in 1868. In it he described how breeding within a species could lead to animals groups, races, with very different traits. In other words, man could steer physical development in a certain, desired direction and these traits would be inherited by the offspring. But these traits seemed to be reversible: animals interbred with other races would revert to a more 'primitive' state, a previous set of characteristics without the extremes. Creating a dog that was no longer a dog but another animal is impossible. There is no evolution here is the idea of some groups of people.
In his article Brouwers describes many examples of dog races or breeds that are hampered by mental and physical illnesses to the point where they are better off being put to sleep. It is not a dog, it is many or all dogs of a breed. Breeders use very small samples of their race stock to breed, only animals that fit their desired traits are allowed to breed. In biology this is known as a genetic bottle-neck. The bottle-neck increases the frequency of desired traits, but also of unwanted ones. Quite often they are coupled because of DNA closeness.
It is nonsensical to re-iterate all problems that Brouwers describes for the poor dog. There's plenty of evidence out there and even the cynology societies do agree that there is a major problem here. They then concentrate on how to circumvent the breeding problems without addressing on why breeding is hazardous in the first place. They talk about widening the breeding group, extending the family tree, the bloodline. Not too much, that damages their business. Some governments are indeed trying to interfere.
What can we learn from this phenomenon? Evolution is nonsense: you cannot create new species out of existing species? Breeding cannot better what the Lord has designed? Breeding has gone on for ages and no new species has 'evolved' out of breeding. You cannot interbreed different species, so where do the new species come from? Not from evolution, hey, some people argue.
Also, creating different races from a general design platform is counter-productive if you're not careful. Cows have been bred by careful selection, being less aggressive, giving more milk, more flesh, more calves, each generation. This process has also been going on for ages and still a cow is no different from its wild predecessor. They can interbreed and have healthy offspring. There is no new 'cow' species. There's no evolution here, so some people think.
The list goes on, but let us take a closer look at dog-breeding as an example. Brouwers shows clearly that dog-breeding leads to symptomatic misery, malformed snouts, weak limbs, bad backs and eyes, all sorts of illnesses. Breeding is nothing short of selection or should I write Selection? It aims to enhance some favoured trait but leads to degradation of the bloodline. Does this indeed prove that Selection cannot lead to evolution, or should I say Evolution? Is Evolution through Selection impossible?
Most of us are aware that Charles Darwin wrote On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life (1859). He writes about Favoured Races, which are, what? Darwin writes about Natural Selection which is, what? What if Selection is manual selection, selection by man, by breeding?
Is man-made breeding and selection the same as Natural Selection as described by Darwin? Are the effects of human selection identical to those of natural selection? Well, let us go to same extremes as dog breeders do. Let us set up an experiment with a higher mammal, say a monkey, ape or so. We pick a few characteristics that we favour: animals with large skull and brain, less hair, bigger noses, willing to walk upright, small teeth, tendency to pick up and use tools. We collect a large enough population size and select on these traits. Animals we do not want to reproduce we kill or at least we sterilise these. We will repeat this experiment for many generations, tens or preferably hundreds. Will the resulting animals be a different race or a different species? Will the animals be smarter, larger, more upright and in general more human-like?
Now we go to the Ethics Committee to obtain a permit. Will we get it, you think? Ah no? Now, how are we going to solve this? Turn to the Fédération Cynologique Internationale and other Kennel Clubs! The breeders have performed this experiment for thousands of years already. Of course we see that there are intermediary dogs between all races. Therefore they will be able to interbreed. That's because it is human breeding and not natural selection. Natural selection will weed out the intermediate animals through competition, for food, for mates, for space. In nature only the extremes survive.
Now we can do the same. Make sure that only the extremes breed and prevent the others from breeding. That will leave only the extremes, Chihuahua and Great Dane for example. They cannot interbreed without help.
If you continue long enough you will create by hand two species, maybe. Or both may die out due to a collection of assorted medical and inherited mishaps. Isn't this failure to survive not a sign of evolution: the Preservation of Favoured Races in the Struggle for Life? Could it not be that we human breeders select for traits that have nothing to do with survival? Breeders concern themselves with what buyers want.
Breeding proves that evolution as understood by biologists is a valid model, because we can show that non-evolutionary selection (by breeding) is non-successful in survival. So, please do not stop breeders from breeding to the extreme. They are running an experiment that supports evolutionary theory and could help to gain additional insights. Sorry for the dogs though but you don't need a permit.
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