A Brief History of Dogs | National Geographic

Long before we raised livestock and grew crops, humans lived side by side with dogs. It's widely accepted among scientists that dogs are descendants of wolves. In fact, their DNA is virtually identical. But how exactly did a fierce wild animal become our loyal companion?

According to DNA analysis, the transformation from wolf to dog began some twenty to forty thousand years ago when people and wolves were living and hunting in close proximity. By about fifteen thousand years ago, dogs were found virtually everywhere people were. But humans may not be able to take all the credit for domestication. Some wolves were already less fearful of approaching people. Those individuals became favored by people for their tame ability. Over many generations, they became tamer and lost some of their predatory qualities, such as big sharp teeth. What resulted was the dog—the very first domesticated animal.

Thousands of years later, humans began to play a more active role in the breeding of dogs. The ancient Egyptians may have been the first to breed dogs for specific uses such as hunting, guarding, and war. In ancient China, dogs were bred to look like lions, an important symbol of the Buddhist faith. Selective breeding eventually gave rise to many different looking dogs or purebreds. By the 18th century, purebred dogs were becoming more of a status symbol among wealthy households.

By the 19th century, the crossbreeding craze was underway, culminating in the first dog shows. By mid-century, humans were mixing and matching dogs, no longer just for their utility but also for their appearance. Today, we have over 300 different breeds, making dogs the most diverse species on earth.

But by breeding offspring that exhibit only the most pronounced traits, some say we've gone too far. In some cases, dogs are the ones that suffer, with genetic disorders in certain breeds that can lead to problems such as difficulty breathing, hip dysplasia, and increased risk of cancer. Yet for all the problems we've introduced into our canine companions, we've also found ways to bring dogs into our lives more than ever before.

Dogs today live among us, not just as our pets, but also as therapy dogs, search-and-rescue dogs, and even war dogs. Humans have also found ways to give back to our furry friends, with advancements in veterinary medicine and establishing rescue organizations to help dogs find good homes. In many ways, the canines that once lived only among their own packs tens of thousands of years ago have come to depend on us as much as we depend on them.