Test time here!
"True" or "false":
Dogs are not wolves.
If you said "True"....oops, you flunked. While there are minor differences, dogs and wolves actually belong to the same genus and species.
But you certainly would not be alone in this belief. Plenty of conventional authors and canine "nutritionists" are calling attention to an article published in "Nature" magazine Jan 23, 2013. This article claims that dogs have only recently developed the ability to digest carbohydrates. We now see many canine nutrition websites blaring the headline: "DOGS ARE NOT WOLVES"! The purpose of such sensational and misleading headlines seems to be to justify the pet food industry's continued abuse of dogs' digestive systems by intentionally feeding them a carbohydrate-based diet like kibbled dog food.
What this study does not highlight, however, is the fact that, genetically, dogs ARE wolves. Based on genetic research done by evolutionary and molecular biologist Dr. Robert Wayne at UCLA, in 1993, dogs were re-classified from Canis familiaris" to "Canis lupus" ssp "familiaris"
In other words, dogs are the same genus and species as the gray wolf. They are merely a subspecies of the grey wolf and do not differ significantly from the grey wolf. All breeds of dogs are still just variations on the grey wolf.
Let's repeat that again, for emphasis. In all significant ways, there is no meaningful difference between the grey wolf and the dog. The gray wolf and the dog share 99.8% of the same mitochondrial DNA. For comparison, the gray wolf and the coyote only share 96% of the same mitochondrial DNA. Dogs are directly descended from the gray wolf, sharing their anatomy and physiology.
The basic definition of a species is the ability to breed and produce fertile offspring, and dogs bred to wolves produce fertile offspring.
Simply because selective breeding in dogs has produced various types and colors, sizes and shapes does not mean that dogs are a separate species from wolves. It's been long established that dogs and the gray wolf have the same genes, and the same basic anatomy and physiology. Based on appearance alone, dog breeds are more dissimilar from each other than these breeds are from their prototype ancestor, the grey wolf. Are Chihuahuas a different type of animal than a Scottish Deerhound? Nope. Any difference wrought by human selective breeding could be wiped out in just a generation or two of breeding back to the grey wolf.
However, let's examine the digestive tract, which seems to be the "proof" that is spurring this recent claim that because dogs can digest carbohydrates, they are therefore separate and distinct from wolves. Dogs and wolves both have jaws that move only up and down, not side to side, with teeth that mesh in a scissors-type fashion. Their sharp pointed teeth are meant for shearing, not grinding. They are carnivores. Omnivores and herbivores have flat molars and jaws that can move in a side-to-side fashion designed for grinding grains, fruits and vegetables. Neither dogs nor wolves have saliva that produce amylase (the enzyme that begins digestion of starch in the mouth). Dogs and wolves both have short intestinal tracts, designed for quick digestion of proteins and fats. Vegetable matter takes many hours to digest and process in an animal's gut. Unless carbohydrates in the diet are highly processed and refined, they are not able to be digested and absorbed by dogs.
And we all know how much valuable nutrition is left in processed, refined foods, right? Think white flour or white rice. Nothing left there but "empty calories"....or so dieticians have informed us for years. Virtually no vitamins or minerals remain after processing. But now, we are supposed to believe that empty calories are beneficial for our canine pals.
The dog's liver produces all the vitamin C he ever needs. No need to derive that from fruits. There is, however, a significant need for specific amino acids in large quantities in the diet, particularly during growth and development. Proteins that are complete, in significant amounts, are necessary to keep a dog healthy. Rather than try to keep complete proteins at the essential bare minimum, dogs should be fed more in line with their natural diet which is protein-rich. No need to feed your dog on the "minimum wages of nutrition" that are so stingily provided in commercial foods.
It is well-documented in multiple studies that unless a dog has kidney or liver disease, protein in the diet does not pose any sort of health risk whatsoever. Even elderly dogs with compromised kidney function related to old age do better with higher protein than was currently believed to be "safe".
The fact that dogs (and wolves) can ingest some carbohydrate-based foods is not a secret, nor is it any new development. Check any scientific wolf website and you will find that wolves do eat fruits, vegetables and berries in small amounts. However, at issue is the huge percentage of carbohydrates that we feed the domestic dog in the way of commercial dog food. (Usually well over 50% carbs). No wolf or indeed any canid can remain healthy on a diet that is primarily grain-based carbohydrates.
In fact, recent studies on HUMAN diet demonstrates that high amounts of carbohydrates are unhealthy for us, too. Since mankind began to farm, and agriculture "improved" our lives to provide us a diet based on grains, the human brain has become significantly smaller. Vegetarian humans also have smaller brains than their omnivorous counterparts. Hmmm. Why even herbivores like cows are said to thrive more healthily on diets where they graze on natural grasses and vegetation instead of being fed strictly grains in a feed lot.
Evolution over 10,000 years of domestication has failed to produce any significant mutations that separate dogs from wolves to the extent that they have evolved into a different species.
For some reason, folks out there....veterinarians, dog food companies, canine "advisors"...are just itching to turn back the clock of genetic science and molecular biology and convince us that dogs and wolves are DIFFERENT. After all, you can tell just by looking at them...it's obvious, right?
Wrong again. Looks only show us the characteristics that man has intentionally bred for. All those characteristics had their potential in the genetic makeup of the wolf. THAT is what should be obvious to anyone with a background in science.
It's convenient for some to attempt to justify the recommendation for feeding a cheap diet based on grains, and to try to support the status quo of using inferior foodstuffs from the dregs of the human food chain, but it also is disingenuous to our claim of caring enough about our dogs to want to provide them with optimal nutrition.
Vrydag 08 Februarie 2013
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