Differences in Dog Morphology
The selective breeding has created many differences in dog breeds than in any other animal species. As for the size, dogs can be as tiny as the Chihuahua and/or as gigantic as the Irish Wolfhound going through all the intermediate sizes between these two.
The complexion can enormously vary as well, from the flattened and elongated profile of the Dachshund to the haughty slenderness of the Saluki. The incredible difference among sizes, complexions and temperaments of different canine breeds is caused, in some way, by the genetic malleability of this species, but it is also the result of human participation, responsible for an intense selective breeding aimed to promote certain physical or personality traits that improved the development of the dogs when putting determined tasks into practice.Dog Toys & Collars
"SNEAKING" INTO ANY HOLE
In general, the shape of the body reveals the function carried out by each of the breeds. For example, the dogs bred to penetrate into the underground hideouts, looking for fast and sometimes fantastic preys are usually small and slim but also strong and very agile, as the majority of the Terriers. Even when there are also big size Terriers, such as the Airedale, the aspect of the Jack Russell, the Cairn and the Border clearly reveals their old trade of being minor hunt predators.
RAPID AND WITH A GREAT SIGHT
On one hand, race dogs are usually tall, so they can detect their preys in a better way in open lands, thanks to their great sight and their bodies designed to let them reach very high speeds, even when running relatively short distances. The English Greyhound and the Spanish Greyhound are typical examples of racing dogs. It's fine and covered with very short hair, reveals the animal's slim and athletic figure, specifically designed to sprint but not to run very long distances. These dogs, with their wide and deep chests and their long paws are able to run short distances to an incredible speed with almost no effort and with no fatigue at the end of the race.
The complexion of the Lebrels is very similar to the fastest animal on earth, the chita, capable of reaching speeds of 129 km/h. In spite of that fact, their speed is a lot lower than that, since they can't get over 70 km/h. In any case, they widely surpass their ancestor the wolf, that can't run faster than 56 km/h.
On the other hand, there are other canine breeds that were bred to run very long distances with no rest, but at more discrete speeds. The Siberian Husky, the Alaskan Malamute and the common dog are more resistant than the sprint runners and they possess fat reserves that aloud them to resist during long trips. These dogs are no longer used as pulling dogs for long distance transportation in sleds in some of most inhospitable and coldest regions of the planet. They normally trot instead of running, which lets them save their energy and slowly use their reserves.
STRONG, BUT NOT FAST
The dogs exclusively bred to keep and protect have solid, almost squared, bodies that make them very strong and take the speed away from them. The idea is to create a formidable, impotent and powerful guardian, even by sacrificing the animal's agility. Its bones are usually robust and thick, but its head and neck can turn to be disproportionately wide, compared with the rest of the body. The Rottweiler and Mastins are typical examples.
The biggest differences among the current canine breeds are caused by the man, who, having more free time in recent historical ages began to choose his dog exclusively for its physical aspect and not for its working capacity. However, the selective breeding aimed to promote specific physical features has had a negative influence on dog's health and caused numerous hereditary diseases and physical problems, such as:
- The shape of the eyes and the facial folds of the Shar Pei and the Bloodhound for example. They have been exaggerated up the a harmful point for the sight.
- The disproportional elongation of the Teckel's spinal column for example. It can provoke serious dorsal problems as the time goes by, specially on the most aged individuals.
- The excessive increment on the height and weight can also cause health problems. The gigantic breeds, as the Saint Bernard for example, are susceptible to suffer from cardiac problems, which considerably shortens its life span.
- Some breeds have been morphologically altered, up to the point in which the females are often incapable to give birth without help. The head of the Bulldog puppies for example, is so big that it can't get through the birth channel, reason why it is mandatory to practice a caesarean. Dog Training Collars