Does Size Matter? Galileo, The Outer Limits, and B-Grade Science Fiction.



AKC GAZETTE MARCH 2014
Cardigan Welsh Corgi Breed Column


In many breeds, the topic of size (too large or too small) comes up frequently and Cardigans are no exception. Such conversations can turn acrimonious when it comes to discussions of the breed. The current AKC standard states that ideally, dogs should be from 30 to 38 pounds; bitches from 25 to 34 pounds and that “Overall balance is more important than absolute size”. However, the first AKC Cardigan standard published in 1938 lists the preferred weights as dogs from 18-25 pounds and bitches from 15-22 pounds.

So what happens when a breed becomes larger over time? Galileo understood this in 1638 and discussed it in his work “Two New Sciences”. Interestingly, he was under house arrest for heresy at the time. Although Galileo wasn’t writing dog standards, he did note that there was a limit to how large something could become. Commonly know as the square-cube law, it simply means that as an object becomes larger, it becomes exponentially heavier and the weight increase is disproportionate to that of size. In his 1926 essay “On Being the Right Size”, geneticist Jack Haldane also noted that there was an upper limit to the size an animal could become, without physically breaking down. So when you were terrified as a child by such science fiction classics as “Attack of the 50 Foot Woman”, “Them” (Giant Ants), and “Night of the Lepus” (Giant Rabbits), there was no reason to be scared. These monsters would not even be able to step out of bed in the morning without breaking their legs! On the other end of the spectrum, “The Incredible Shrinking Man” would have been unable to breathe as his lungs would have collapsed.

So what does this have to do with dogs? The difference in weight among pure bred dogs is almost 50 fold, ranging from the diminutive Chihuahua to the massive English Mastiff; A Mastiff is not simply a Chihuahua enlarged via photoshop. Due to the increased weight predicted by the square-cube law, a thicker bone and musculature is needed to support the greater mass.

A physics professor once used the example of injured athletes as an example of the effects of the square-cube law. Why is it that these athletes, more physically fit than most people, seem to sustain injuries frequently? Certainly they are involved in a physical sport, but being larger and heavier than the average human, they hit the ground harder and their bones/muscles/joints are not significantly different than the average person As size increases, so does the chance of a mechanical failure. It is not something that happens all at once, but increased size results in increased stress. This is not to say large dogs are more prone to injury, but rather that a dog’s structure must change to support the larger size and so you will never see a Chihuahua the size of a Mastiff, nor a Great Dane the stature of an Affenpinscher. Breed standards were developed over many years and in the case of the Cardigan, sizes and weights are suggested ranges and I would suggest that breeders take the AKC standards seriously. Just some food for thought!!!

Corregium: In the last column the first Cardigan Specialty was listed as being held in 1938. It was actually held in 1936.

Currently Cynthia and Jeff; CymbrogiCardigans@msn.com; live on a small tree farm and wildlife refuge in rural North Carolina and are members of the Cardigan Welsh Corgi Club of America.


First published in the AKC Gazette Digital Edition, June 2014

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