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Michael J. Pieropan
ENVS 02: Human Nature, Technology and the Environment
Professor Everbach
Essay 1: Relationship between Early Humans and their Environment
February 6, 2006
Of all the members of the animal kingdom, canines truly are “man’s best friend.” I can personally attest to the companionship that man feels towards dog, as an image of my Labrador Retriever is currently displayed on the background of the laptop on which I write this very essay. This relationship is far from a modern occurrence – man and canine have shared a friendly bond for thousands of years. Archaeologists in Israel have discovered evidence of humans being buried alongside dogs as long as 12,000 years ago (Pennisi 1540). The relationship is mutually beneficial, as each species profits from the other. In modern times, canines are provided with nourishment and shelter in exchange for their services of protecting and offering companionship to humans. In considering the relationship between human and dog, special attention must be given to the initial establishment of the bond. Specifically, it is vital to debate whether the domestication of canines was initiated by Homo erectus man, or whether dogs domesticated themselves to reap the benefits of friendship with man.
The evolutionary history of dogs is a subject plagued by controversy. Most experts agree that dogs evolved from wolves. However, only subtle genetic differences distinguish the two species, making it extremely difficult to accurately identify the date and geographic location of the transition. Estimates of the date of domestication range from as early as 135,000 years ago, and numerous countries have claimed their land as the dog’s first homeland, including Italy, Israel, and various central European and German nations. A well-designed study by Dr. Peter Savolainen, which analyzed DNA samples from various wolf and dog populations around the world, concluded that the domestication of dogs occurred approximately 15,000 years ago, in East Asia (Wade).
Along with the controversy surrounding the date and location, debate also centers on the issue of what species initiated the domestication process. Given that mutually beneficial nature of the relationship, one can recognize incentives for either party to desire domestication.
Humans were able to reap various advantages from their companionship with domesticated dogs. Arguably the most important of these benefits was protection. Humans became vitally dependent on dogs to provide an early warning signal, in the form of barking, to alert them of nearby predators. Given the nocturnal nature of the human species, the existence of guard dogs could have single-handedly been responsible for the human survival in certain places and times. In addition to protection, domesticated dogs were a reliable source of warmth, especially at night, and may have served as assistant hunters. In times of scarce resources, canines functioned as an emergency source of food. In addition to the ‘practical’ benefits afforded to humans vis-à-vis their relationship with dogs, one cannot overlook the simple advantage of companionship; early humans must have obtained some degree of fulfillment simply from their personal relationship with the animal species.
Inversely, dogs were also able to acquire direct benefits from their relationship with Homo erectus. The most obvious advantage was that dogs were provided with food and shelter. While dogs may have assisted humans on hunting excursions, there were presumably times when dogs were simply allowed to scavenge off of the scraps left over by humans. As compared to having to hunt in packs, being fed by humans provided a much easier means to obtain nourishment. While dogs provided humans with protection, one could also assert that humans granted a certain degree of protection for the domesticated canines. Given that Homo erectus was higher up on the food chain than wolves, one can assume that there were instances in which predators were diverted from their stalking of the dogs by the presence of humans.
Considering the benefits offered to both parties via their mutual relationship, it is of considerable difficulty to accurately assess the circumstances leading up to the ultimate domestication process, specifically which species initiated the process. The comprehensive answer is most likely that both parties were partially responsible for initiating and accelerating the domestication process. Nonetheless, one party must have been more aggressive in desiring and implementing the companionship. Taking into account the length of the domestication process, my hypothesis centers on the notion that wolves were more responsible for domestication – in short, wolves domesticated themselves.
“Domestication is an arduous process, in which animals must be selected for a particular trait through many generations, by several generations of people (Wade).” A study started by Dr. Dmitry Belyaev and completed by Dr. Lyudmila Trut focused on domesticating the silver fox, using tameability as the characteristic of interest. After selecting from 45,000 silver foxes for over 40 years, the experiment produced only 100 domesticated foxes (Wade). The study revealed the painstaking time and dedication necessary for domestication of a wild species. The domestication of wolves into dogs was not an instantaneous transformation. Rather, it was a very gradual process that may have taken upwards of 100,000 years to result in full domestication.
Throughout the majority of its existence, the collective life of Homo erectus can be classified as a “15-minute culture (McCrone 34).” Individuals constructed simple tools for immediate use, and then discarded them when they were no longer necessary. H. erectus lacked the cognitive abilities to consider the ‘big picture.’ As pertains to domestication, humans wouldn’t have been able to comprehend the far-reaching implications of domesticating wolves. H. erectus would have only been able to understand the short-run benefits of domestication, much like they could only realize the immediate advantages of tools. Given the length of time necessary to achieve domestication, the benefits for humans in the short-run were minimal. Wolves were not tame enough to provide many of the benefits eventually afforded through domestication. At the outset, it was much more beneficial for wolves to be associated with humans than it was for humans to be linked with wolves.
Evidence to support the hypothesis that wolves domesticated themselves can also be drawn from the fact that all breeds of dogs descended from the same population in east Asia. If dogs had descended from different groups of wolves, then the process of domestication would have arisen independently in various areas and times of the world. If such were the case, one could assert that various groups of humans realized the potential benefit of close association with dogs, and it would have thus been plausible to reason that H. erectus initiated the domestication process. However, genetic evidence gathered by Dr. Savolainen concludes that dogs evolved from wolves exclusively in east Asia. Since the greatest genetic diversity was found amongst Asian dogs, one can conclude that “this population is ancient enough to have accumulated unique genetic signatures (Pennisi 1541).”
Given that the domestication process occurred only once, one can speculate that there was something particular about the wolf species that equipped it with the inclination to associate with humans. The hierarchal structure of wolf packs translates into the observational fact that the wolves that were less proficient hunters would be forced to rely on scavenging for food. Since human settlements were an optimal location to scavenge, these wolves would have the incentive to be less aggressive towards H. erectus. Eventually, the wolves that learned to be the most comfortable around humans came to flourish – it soon became evolutionarily advantageous for wolves to befriend humans. As wolves became increasingly docile, human desire for companionship (and the so-called ‘cuteness’ factor) would have supplied individuals with the longing to keep baby wolves for pets.
As the domestication process intensified, dogs began to evolve genetically to optimize the benefits of their relationship with humans. Similar to the evolution of wheat, canines ‘made the most’ out of the association by gradually developing the characteristics ideal for such a close relationship with humans. Dr. Brian Hare conducted an experiment that proved dogs have the unique ability to interpret human cues. Dogs were able to correctly identify the container that a human was looking at or pointing to much more frequently than any other animal species, including highly-intelligent primates. A subsequent study proved that these abilities were innate, as puppies with minimal exposure to humans also possessed this trait (Pennisi 1542).
While admittedly hypothetical and controversial, one can put forth the plausible suggestion that wolves were primarily responsible for domesticating themselves. Given the considerable duration of time necessary for domestication, coupled with the limited cognitive abilities and foresight of H. erectus, wolves were the primary benefactors of their relationship with humans at the outset of the process. In all likelihood, both wolves and humans contributed to the domestication process, but one can speculate that wolves were primarily responsible for initiating the development.
Bibliography
McCrone, John. “Fired Up.” New Scientist. May 20, 2000. Pgs 30-34.
Pennisi, Elizabeth. “A Shaggy Dog History.” Science Magazine. Vol. 298. November 22, 2002. Pgs 1540-1542.
Wade, Nicholas. “From Wolf to Dog, Yes, but When?” The New York Times. November 22, 2002.
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