When you compare a Chihuahua to a Great Dane, it’s difficult to comprehend that the two are the same species. Especially when there are much more similar looking creatures who are completely different species, such as rats and mice. The domestic dog is part of the genus canis familiaris. Within that genus there are very few genetic differences, despite the huge variance in size, appearance and behavior.
Domestic dogs are all a member of the same genetic subgroup, or genus, called canis familiaris. This is because they all descend from the same ancestor, the wolf. No other species displays such variety across a single genetic order. All dogs share common genetic traits, although some are more distinct than others, such as greyhounds and basenjis. Some dogs are more closely genetically related to the wolf than others, such as huskies.
Although one species, there are some genetic differences between dog breeds. This is because the wolves from which dogs descended through domestication, were beginning to become diverse at the time of man’s intervention. Distinct groups of wolves had become geographically isolated and had begun to adapt to different environments. So although dogs have the same ancestral species, that species had begun to display genetic diversity and the results still show today. For example, the Norwegian elkhound is more closely related to the Russian wolf, while the German shepherd is more closely related to the North American wolf.
Other canidae species display a much more distinct genetic profile. For example, although he resembles his domesticated cousins, the African hunting dog is genetically distinct and is in fact, the only member of the canis lycaon order. Wolves too, are genetically distinct from domestic dogs, despite their close ancestral relationship to the common pooch.
The huge variance in appearance, size and behavior among dogs is due to human intervention. Domestic dogs are a result of man’s actions. We selectively breed dogs to look and behave a certain way. This practice has taken much of the control away from Mother Nature, who when left to her own devices, creates much more consistent results.
Evolution takes a long time. A wolf today will look almost identical to his ancient ancestors. However, where dogs are concerned, man has taken on nature’s role in choosing which dogs mate with which, effectively speeding up the evolutionary process. In doing so, we have drawn out the potential differences in size, color, shape, coat type, behavior and personality, something that would have taken nature thousands of generations to achieve. This is why the single canine species has such diversity.
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