Sunday, October 25, 2015

2063. Are Cats Domesticated?

By Ferris Jabr, The New Yorker, October 23, 2015 


“The cat does not offer services,” William Burroughs wrote. “The cat offers itself.” But it does so with unapologetic ambivalence. Greet a cat enthusiastically and it might respond with nothing more than a few unhurried blinks. Later, as you’re trying to work, it will commandeer your lap, keyboard, and attention, purring all the while. A cat will mew at the food bowl in the morning and set off on a multiple-day trek in the afternoon. Dogs are dependent on us to the point of being obsequious, but cats seem to be constantly reëvaluating the merits of our relationship, as well as their role in domestic life. “Are cats domesticated?” is one of the most frequently Googled questions about the animals, based on the search engine’s autocomplete suggestions.

It’s a question that scientists have been asking, too. The latest answer, based on insights from recent archeological discoveries and genome-sequencing studies, is that cats are semi-domesticated. Conventional wisdom holds that the ancient Egyptians were the first people to bond with the cat, only four thousand years ago. In 2004, however, a team of French researchers working in Cyprus unearthed the ninety-five-hundred-year-old remains of a human and a cat buried side by side. Last year, an analysis of cat bones and teeth from a fifty-three-hundred-year-old settlement in China indicated that the animals were eating rodents, grains, and the leftovers of human meals. It appears that, following the advent of agriculture, wildcats in the Near East and Asia likely began to congregate near farms and grain stores, where mice and rats were abundant. People tolerated the volunteer exterminators, and wildcats became increasingly comfortable with people. Whether this affiliation began five or ten millennia ago, the evidence suggests that cats have not been part of our domestic domain for nearly as long as dogs, who have been our companions for perhaps forty thousand years.
At first, the cat was yet another opportunistic creature that evolved to take advantage of civilization. It was essentially a larger version of the rodents it caught. Somewhere along the line, people shifted from tolerating cats to welcoming them, providing extra food and a warm place to sleep. Why? Perhaps because of the cat’s innate predisposition to tameness and its inherent faunal charm—what the Japanese would call kawaii. Look up photos of the thirty-eight or so wildcat species and you might be surprised at how easy it is to picture one curled up on the couch. Dogs likely initiated their own domestication, too, by prowling around campfires in search of food scraps. Whereas our ancestors quickly harnessed dogs to useful tasks, breeding them to guard, hunt, and herd, they never asked much of cats. We have also been slow to diversify cat breeds. Many dog, horse, and cattle breeds are more than five hundred years old, but the first documented cat fanciers’ show didn’t take place until 1871, at the Crystal Palace, in London, and the most modern cat breeds emerged only within the past fifty years.

This relatively short and lenient period of selective breeding is manifest in the cat genome, Wesley Warren, a geneticist at Washington University in St. Louis*, said. In a study published last year, Warren and his colleagues analyzed DNA from several wildcats and domestic cat breeds, including an Abyssinian named Cinnamon. They confirmed that, genetically, cats have diverged much less from their wildcat ancestors than dogs have from wolves, and that the cat genome has much more modest signatures of artificial selection. Because cats also retain sharper hunting skills than dogs, abandoned felines are more likely to survive without any human help. And in some countries, feral cats routinely breed with their wildcat cousins. “There’s still a lot of genetic mixing,” Warren said. “You don’t have the true differentiation you see between wolf and dog. Using the dog as the best comparison, the modern cat is not what I would call fully domesticated.”

Not all researchers agree. “I don’t think it makes sense to talk about animals as semi- or fully domesticated,” Greger Larson, a paleogeneticist and archeologist at Oxford University and an expert on domestication, said. “Any threshold you try to define will necessarily be arbitrary.” Larson tends to agree with the views of Melinda Zeder, an archeologist at the Smithsonian Institute, who has written extensively on the domestication of both plants and animals. Zeder characterized domestication as an ongoing symbiosis between humans and another species—“a sort of pact that ends up being mutually beneficial,” she said. This relationship, she argued, can follow many paths and result in somewhat different outcomes, which she has catalogued. Sometimes people gradually domesticate a prey species—sheep, goats, cattle—or deliberately remove non-prey animals from the wild and breed them for a specific purpose, as we’ve done with horses. In other cases, hunger draws a wild animal—dogs, chickens, guinea pigs, cats—to human society, where it becomes increasingly tolerant of people. Even a single domestic lineage can contain varying degrees of dependency and a range of temperaments.

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