The use of dogs and other animals solely for companionship is not confine to the modern affluent societies. The keeping of dogs as pets is widespread among relatively simple hunting and foraging societies. The Comanche Indians of North America possessed only two domestic animals, the dog and the horse. Horses were an indispensable part of the Comanche economy, yet the Indians regarded them entirely as useful objects. In contrast, dogs served little if any economic function, yet they were treasured as pets; warriors pampered them, carried them on horseback to prevent them from getting sore feet, and regarded the loss of one dog as far worse than the loss of several horses.
Even in societies where dogs were economically important, their role as a champions was frequently acknowledged. In Polynesia, where dogs were often eaten, it was common for particular puppies to be adopted and raised as pets by the inhabitants; usually such companion dogs were exempt from slaughter. In spite of so much evidence it is only since the 1970s that scientists have begun to research and evaluate the reasons why the companionship of dogs so important to the mental and physical health of highly industrialized societies.