Dogs are thought to be the very first animal ever domesticated by humans, and the only large carnivore to ever be domesticated. The first undisputable evidence of domesticated dogs dates back over 14, 000 years – this evidence being a dog buried with humans. There is some other evidence that may suggest domestication as far back as 36, 000 years ago.

Interestingly, a key event of human evolution dates back to a time just prior to evidence of early dog domestication – the disappearance of the Neanderthal species. Neanderthals were thriving in Europe before homo sapiens ever arrived there, but somehow, homo sapiens managed to outcompete their evolutionary cousins, resulting in their extinction, around 40,000 years ago. It is the theory of Pat Shipman, PhD, that cooperation with canines allowed homo sapiens to be much more successful than Neanderthals during climate change, a time of extreme vulnerability. Early humans shared similar social structures and cooperative hunting strategies with canines, allowing the two species to coexists in a mutually respectful relationship, eventually leading to emotional bonds.

Dogs and humans have been evolving side by side for thousands of years. We not only see this through archaeological evidence, but through gene analysis as well. A study in 2014 identified that both species underwent similar changes in genes associated with digestion and metabolism as well as in brain processes, like transport of serotonin. It has also been seen through scientific study that levels of oxytocin, sometimes referred to as the “love hormone,” increase in both dogs and humans when they engage in physical contact, just as it does when interacting with individuals of their own species.

Dogs and humans have influenced the evolutionary path of one another and shaped the social world both species live in today. The similarities in gene patterns and hormone activity is not seen with wild wolves, only domesticated dogs that have been our evolutionary partners.

We may not know exactly when, or exactly how, dogs came to be human’s best friend, but we sure are grateful they did.