The legendary partnership between humans and dogs goes way back to prehistoric times. It’s an ancient and complex history that’s still steeped in a lot of uncertainty. What is known, though, is that humans and wolves both modified their behaviors to not only cooperate, but coevolve.
Wolves and humans inherently share a lot of behavioral similarities. They live in groups, usually with a familial core and hierarchy. They hunt and raise young cooperatively. They work together to defend their territories. They engage in play. Both species have complex communication systems to facilitate these highly gregarious lifestyles. While humans and wolves have signals unique to each other, both use a variety of verbal calls, and variable eye contact and postural cues. So when wolves and humans first came together, they did so with relatively high similarity and familiarity. All they had to do was learn and adjust to new types of cues.
Why would the two species come together in the first place? The answer to that question is complex and lacks a single answer.
Scavenging wolves likely came into contact with prehistoric humans in search of food. Wolves may have fed on scraps, or humans may have intentionally fed them in attempt to discourage attacks. The wolves would have protected this newfound food source from mutual hunters/competitors. Perhaps then, seeing this new protection benefit, the humans would regularly feed the wolves to encourage their proximity. Wolves who were more willing to interact peacefully with humans reaped the benefit of food.
Humans could have adopted orphaned wolf pups. They could have felt compassion for an animal that shares so many “human” attributes. Or they may have guessed a wolf would make a good guardian and hunting companion. The hard-wiring of the wolf brain to pick up on shared human-wolf signal types would give the wolf a high taming potential. Humans who took care of wolves would gain protection and companionship, while the wolves, in return, would be fed and cared for.
Ancient humans and wolves both engaged in pastoral behaviors, in the sense that they both followed migrating reindeer herds as a food source. It has even been suggested that humans actually learned this behavior from observing wolves (see The Co-evolution of Humans and Canids). If these humans and wolves cooperated, they may have been more successful hunters than if they had worked alone. The herding behavior used by wolves to single out a weak prey individual and the herding behavior of a sheepdog are similar, suggesting that this behavior could have been conserved and positively selected upon.
Since the domestication of the dog, both species have adapted their behaviors to suit this cooperation. They became better at digesting starches as their diets shifted to include agricultural grains. Dogs use tail wagging as a way to communicate with humans, and have milder temperaments and a decreased prey drive when compared to wild wolves. Humans have used dogs to transport people and supplies, watch over children, help keep warm in long winter months, and as an emergency food source in time of famine. They have been integrated into countless cultures worldwide. People employ selective breeding to further shape dogs to better suit their needs or fancies. Dogs became faithful companions, police and military tools, and therapy animals. The connection is so strong that even the brain chemistry associated with intraspecific interaction has changed. When interacting, especially during extended eye contact, hormones are released in both humans and dogs (but not wolves) that are associated with happiness and bonding, says this article. This affirms that the brain rewards spending time with the respective other.
Neither species would have been the same today without the influence of the other. Dogs may be man’s best friend, but we’re also theirs. 🐾
Co-evolution of Humans and Canids- An Alternative View of Dog Domestication: Homo Homini Lupus? by Wolfgang M. Schleidt/Michael D. Shalter. Evolution and Cognition. p57-72 Vol. 9, No. 1. 2003
Is the Gaze from those Big Puppy Eyes the Look of Your Doggie’s Love? by Judy Hecht. Scientific American. Scientific American, a division of Nature America, Inc. Apr 16, 2015.