In the United States alone an estimated 50 million dogs, from Akitas to weimaraners, now live in our homes, racking up an annual $6 billion in food bills and $4.5 billion in vet bills, and dumping a daily 20 million pounds of feces at our feet. Some 12,000 years ago, judging from archeological remains, these gray wolves loped into the lives of our hunter-gatherer forebears and then, over the millennia, gave rise to all the fantastic dog shapes and sizes that populate the planet today. Our dogs are derived from gray wolves, which not only also have 78 chromosomes but, more to the point, can still breed with dogs, making them members of the same species. But how did we first come by ours? We need only compare the number of chromosomes- DNA bundles-in members of the canine family to see that our dogs aren't descended from foxes: silver foxes have just 36 chromosomes, whereas dogs have 78. That's how Belyaev got his version of a domesticated dog. In a bid to create more manageable foxes for the fur industry, Belyaev began selectively breeding for tamer animals in 1958, transforming hostile, pointy-eared silver foxes into friendly, floppy-eared fox-dogs in a mere 20 generations. Prized for their fur, these wild and normally skittish animals reached their tame, doggielike state at the hands of Dmitry Belyaev, erstwhile director of the city's Institute of Cytology and Genetics. The reason they're remarkable is that they're not domestic dogs at all-they're silver foxes (known as red foxes in the United States), separated from Rin-Tin-Tin and Lassie by 12 million years of evolution. They wander up to the geneticists working there, yapping, sniffing, and licking their hands much as any domestic dog might do. They don't look odd, mind you, with their piebald coats, floppy ears, and wagging, upturned tails. In the sprawling Siberian city of Novosibirsk, there's a research compound that's home to some of the world's newest and oddest dogs.
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