The Viral Storm by Nathan Wolfe Page A

large fees for medical expenses and mourning for them when they die. Sitting on the beach near my home in San Francisco, it would be hard for me to spend an hour without seeing someone kiss his or her pet dog on the mouth. Watching that woman in Paris sharing a meal with her dog solidified just how linked we are to these animals.
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    The close relationships we have with dogs, whether as companions, work animals, dinner guests, or a source of food, should not surprise us. Dogs play a special role in human history. If we were to compile the “greatest hits ” of human evolution, hunting and cooking would certainly make the cut. Language and the capacity to walk on two feet would also be on the list. But central among our species’ critical historical events is domestication—and dogs were the first in a long line of plants and animals that our ancestors tamed.
    The capacity to domesticate plants and animals underlies much of what we now think of as being human. To imagine a world without domestication, we’d have to spend time with one of the few dozen human populations on the planet that still practice hunting and gathering lifestyles, groups like the Baka and Bakoli, the so-called pygmies, living in central Africa that I have worked with for years, or the Aché that live in South America. For these groups of people, there is no bread, no rice, no cheese. There is no agriculture, and therefore the many rituals of our planet’s major traditions, including the harvest and planting pilgrimages and their associated festivals, are entirely absent—no holidays such as Ramadan, Easter, or Thanksgiving. There is no wool, no cotton, only textiles made from wild tree bark or grasses and the skins from hunted animals.
    These hunter-gatherer populations have complex histories, and many of them lived at some point with some form of agriculture before returning to a foraging lifestyle. Yet they provide us with interesting clues on what the lives of our ancestors looked like before the advent of widespread domestication. 1 Among the traits hunter-gatherer populations share are small population sizes and a nomadic lifestyle. As we’ll see, these traits have an important impact on keeping the microbial repertoires of these populations at low levels.
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    The first human foray into domestication came with modification of wolves into the canines we know today. Archaeological and DNA evidence suggests that populations in the Middle East and east Asia began domesticating gray wolves as early as thirty thousand years ago, turning them into guard dogs and work animals as well as using them for food and fur. The early history of dog domestication is still unclear. One hypothesis is that wolves followed humans, scavenging off of their kills, and over time became dependent on humans, a dependency that set the stage for their later domestication. But no matter how it began, by fourteen thousand years ago dogs played an integral role in human life and culture. In some archaeological sites in Israel, humans and dogs were even buried together. These early dogs would have resembled modern-day basenjis, the silent hunting dogs preferred by the central African hunters with whom I work.
    Occurring around twelve thousand years before we would domesticate anything else, the domestication of the dog was an early precursor to what would follow. Around ten to twelve thousand years ago, a domestication revolution occurred in earnest, starting with sheep and rye and then followed by a diverse group of other plants and animals.

    Female Basenji dog. ( Dave King / Getty Images )
    The consequences and opportunities of the domestication revolution were profound. Prior to domestication, human populations were limited by the food available in wild environments. Wild animals migrate, which forced our ancestors, who were dependent on the hunting of these wild animals, to do the same. The wild fruits and other plant foods present in the local