In both the United States and Australia, 63% of households include pets, compared to 43% of British and 20% of Japanese households. In the United States, the proportion of households with pets is larger than those with children (522).
This relationship, dubbed the animal connection by Shipman, may have played an important role in human evolution, linking the traits that distinguish Homo sapiens from other mammals. How is it that some animals transitioned from food to friends, and what is the significance of this relationship?
The animal connection is the process by which pets or livestock become companions and/or partners, and are treated as members of the family. It refers to the close relationship between animals and humans starting 2.6 million years ago (mya), beginning with the use and study of animals by humans, and leading to regular social interactions. Today this is manifested in the adoption of animals and the care provided to them in the course of that relationship. The roots of this relationship may be found in the development of three often recognized traits of humans: making and using tools, symbolic behavior (including language, adornment, and rituals), and domestication of other species. Shipman views the animal connection as a fourth trait, tying the other three together and having an immense effect on human evolution, genetics, and behavior (2010: 522).