COURTESY OF LowCountryBookstore : Dogs have been part of our families for so long that we often think of them as little (and entirely well-behaved) humans. Sometimes, we forget that they're and entirely different species. They do things for reasons that have nothing to do with us - reasons that, in some cases, are millions of year old. "Ancient Instinct and Urges". Although dogs have been living with people for a long time, some of their behavior has its origins in their ancestors' days in the wild, a time when dogs had to be totally self-sufficient an order in survive.