Loyal, lovable, and protective of us and our property, dogs have been our best friends since the last Ice Age, as a 27,000-year-old painting of a child and a dog on the walls of the Chauvet-Pont-d’Arc cave in France bears out. Studies showing that the companionship, unconditional love and sense of well-being that dogs provide make us happier and healthier just confirm what dog owners already know. Most people also know that domesticated canines descend from wild wolves but may not be aware that the affinity we have for them, whether they’re Maltese, Mastiffs, or mutts, is a result of brain chemistry.
“There is a very powerful brain chemistry that bonds humans to animals,” says Meg Olmert, author of “Made For Each Other: The Biology of the Human-Animal Bond” and writer of “And Man Created Dog,” a two-hour National Geographic Channel special. “When I pet a dog and look into her eyes, it’s releasing a brain chemistry in me that was designed to bond mother to infant and to allow all of us to see one another as kin.”
Specifically, she’s talking about the hormone oxytocin, which is synthesized in the nerves of the hypothalamus and secreted from the pituitary gland during labor, nursing, and sex, and is believed to play a role in social bonding in humans and animals. “When you say, ‘This dog is my baby, a member of my family,’ you’re not crazy. It’s the same chemistry that bonds mother to infant,” Olmert explains. “When you lose that animal, the neurochemistry crashes, just like when you lose a loved human. You are literally heartbroken. The chemistry that protected your heart is gone.”
The same chemical bond played a role in the domestication of early canines, Olmert says. “It’s how you would take a wild wolf and calm it down, and allow it to see us as its pack and transfer loyalty and love to us,” she says. Over the millennia, that process facilitated the development of dogs into hunters, herders, rescuers, and protectors, bred for traits and abilities that differentiated the species into the most diverse mammals on the planet. The evolution that produced tiny chihuahuas and massive Great Danes, smart border collies and poodles (numbers 1 and 2 on the canine intelligence scale) and, more recently, designer hybrids cultivated for looks, temperament, or hypo-allergenic qualities, has helped humans evolve, as well.
“By having this relationship, man was able to progress much faster,” says Pierre de Lespinois, director of “And Man Created Dog.” “Dogs were a very important part of our development. It’s a relationship that started more than 20,000 years ago and is flourishing today. We’re just rediscovering how much they really meant and what they did for us.”