In order to trace and examine the biological history of the bloodhound breed, we must look back in time to the domestication of the dog as a species. It might be tempting to ask, why stop there, why not trace canine history all the way back to the dog’s progenitors, the wolves, or other Canis species such as the jackal or fox? While the species Canis Lupus Familiaris shares 99.96% of their genes with the Grey Wolf, and inherit traits of sociability and adaptability from their greater canine ancestors, there is a fundamental difference between the domesticated dog and other members of its family (Bradshaw). While scientists often focus on biological differences such as physical traits or adaptations, they often neglect the unique behavioral differences that allow dogs to live besides human beings. Dogs inherit from their canid ancestors’ basic body features and capabilities as well as a keen social instinct, but it is the process of domestication has fundamentally altered the way the dog’s brain works. It is however, important to note the genetic predispositions that isolated the dog’s ancestors as better candidates for domestication. Genetic evidence has largely pointed the Grey Wolf as the sole ancestor of the domesticated dog, and thus the question arises, why the wolf and not the fox or the jackal? This may largely have to do with the social structure of the wolf and its adaptability, putting it in contact and often competition with early humans.
" In particular, two developmental milestones were different in the tamer foxes: their eyes opened several days earlier, and their fear response kicked in about three weeks later than the norm for wild foxes. These two events might have worked together to increase the openness of young foxes to interacting with humans and doing so without fear. At the same time, Belyaev found reduced levels of the stress hormone corticosterone in the domesticated foxes. Even the changes in coat color were linked to changes in the timing of development" (Adams)
Archeological evidence dates the domestication of dogs to a single point between 14,000 and 10,000 years ago in Eurasia, placing them prior to the time scale of the agricultural revolution. Although wolves were able to cross the Bering land bridge (along with Humans) into the Americas, providing even more shared environment. Thus, a narrative develops: wolves who were behaviorally more docile would become associated with human hunter-gatherer groups, scavenging instead of competing with them for food, thus becoming selected for dog like traits, eventually leading to domestication. A modern theory and famous experiment correlates with this story. Russian geneticist Dmitry Belyaev theorized that the selection of one trait, such as tameness, could affect other physical traits. He then conducted a multi-generational experiment using silver foxes, choosing the tamest of each generation to breed, eventually creating a population of friendly silver foxes who exhibited dog like traits such as drooping ears and curved tails. Through this experiment, Belyaev proved that the selection of one trait could affect other phenotypic traits painted a picture of how early man may have created the dogs we know of today. The domestication process is analogous to that of the agricultural revolution as explained by professor Speth and similar questions arise: Why was only one species out of the eight possible Canid species domesticated? Like the domestication of agriculture, which was more time consuming than hunting and gathering, the domestication of the carnivorous wolf seemed to use up more resources rather than provide them, so why did domestication occur?
Theories such attempt to answer these questions are mostly inconsistent and do not paint a clear picture for domestication. For example, genetic evidence suggests that there was a genetic divergence thousands of years earlier, prior to agriculture or domestication, hinting that behaviors advantageous to an agricultural society were only later developed and not the main cause for domestication. Stories of failed domestication with other Canids such as the South American fox known as Aguara dogs where full domestication did not occur further complicates this story. Genetic evidence also suggests that the divergence from wolf populations was not linear, instead of evolving directly from the Grey wolf, it was likely that there was a now extinct intermediary, that they shared a common ancestor rather than being a direct descendant, thus marking the difference in behavior between the dog and the wolf (Bradshaw). This paints a very different path for dog domestication, instead of an agriculturally based rearing of animals; it was more likely that large packs of wolves began to tag along hunter-gatherer groups. Instead of a direct domestication of wolves to dogs, there were likely other paths, failed domestications and different population bottlenecks that diverged the paths of the two species. Another possibility is that multiple sites of domestication occurred near simultaneously and eventually converged. What is important here is to recognize the fact that the story of dog domestication is not linear, it can have many dead ends and possibilities, and in the narrative of the dog is one where many different kinds of evidence come together to paint one possible image of how humans and dogs have developed their bond.
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