In a comprehensive examination of ancient canid remains from central California, a group of archaeologists has concluded that dogs were far more numerous in, and important to, the hunting and gathering societies of the time than previously thought. Excavated from interments and middens found from San Francisco Bay to the Channel Islands and dating from the Late Holocene period, which ended with the arrival of Spanish Missionaries nearly 200 years ago, the canid remains were believed to represent a mix of wolves, coyotes, and dogs—an assessment based on their physical characteristics alone. But an analysis of their mitochondrial DNA revealed that virtually all, regardless of their appearance, were dogs.
The finding underscores the difficulty involved in distinguishing dogs from wolves and coyotes, even thousands of years after the species took separate evolutionary paths, and it brings dogs to a more central place in the lives of the prehistoric hunters and gatherers who formed complex societies in central California, where for many thousands of years dogs were the only domesticates, said Brian F. Byrd of the Far West Anthropology Research Group in "The role of canids in ritual and domestic contetxts: new ancient DNA insights from compex hunter-gatherer sites in prehistoric Central California." He coordinated the study and was first author for their article in the April 2013 issue of the Journal of Archaeological Science. (Subscription required.)
They based their conclusions on an analysis of ancient mitochondrial DNA extracted from the roots of teeth when possible. That method leaves most of the teeth intact for future analysis should more sophisticated techniques be developed to extract and decode the fragile material. They also analyzed the diets of dogs and humans at the time and found that in he main the two species ate much the same diet of plants and deer and other herbivores.
The researchers hypothesize that many of the dogs were interred following ceremonial or ritual killings and, sometimes, dismemberment. Some of those ceremonies would probably have involved sacrificing a dog or dogs and serving them to honored visitors. Dogs might also have been consumed in time of famine.
Added to their other roles as beasts of burdens, camp guards, hunting and traveling companions, the use of dogs for celebration and emergency rations underscores their importance to these prehistoric Californians.
Indeed, they were the only domesticated animal among early Americans and for that reason filled many roles later assigned to other domesticates. That fact alone would have made them invaluable. Indeed, it is easy to imagine that the more complex the society in terms of its organization and rituals, the more varied would the dog’s roles have been.
That many of these dogs looked like wolves so many thousands of years after they are thought to have split raises again the question of continued crossbreeding between dogs and wolves, which cannot be resolved by analysis of mitochondrial DNA alone. It could also be the case that in dogs, as in many other species, phenotype follows genotype imprecisely, so that many genetic dogs continued to look like their wild cousins until an injection of other genetic material caused their appearance to change.
Implicit in this study is the notion that once people had dogs, they preferred them to wild canids, probably because they found them more sociable, more predictable, more willing to stick close to home. The persistence of the wild phenotype also calls into question the theories of Raymond Coppinger, Brian Hare, and others who, based on an experiment in directed breeding using fur farm foxes, would make of early dogs sniveling self-domesticating dump divers. They confuse subservience with sociability and foxes with dogs and their wolfish cousins.