The connection between humans and dogs is one that hearkens back to ancient and even prehistoric times. Archaeological evidence of canine domestication dates back some 15,000 years, and some experts believe our interspecies love affair may stretch as far back as 30,000 years ago.
While there is still some debate about just how long we humans have been vulnerable to the charms of big, sad puppy eyes and fluffy tummies, there is no question that our relationship with these animals has evolved greatly over the ages. In the earliest days, dogs helped with hunting and guarding in exchange for a share of the food and the comforts of life in a mixed-species pack.
Today, dogs are primarily cherished companions—four-legged family members. But there are still many who pull their weight by providing all kinds of valuable services to the humans they love.