Archaeologists in China have unearthed the first clear evidence of cats living among humans as semi-domesticated mousers about 5,300 years ago, a heretofore missing link in the history of the world's most popular pet, experts say.
The evidence, published Monday in the Proceedings of the National Academy of Sciences, supports the long-held view cats began their symbiotic relationship with people following the advent of agriculture, many thousands of years after dogs were tamed by nomadic hunter-gatherers.
The discovery fills in an enormous gap in experts' understanding of cat domestication, but it has also thrown them for a curve. In some ways, an ancient Chinese village is the last place researchers expected to find such evidence.
"This was a very unexpected find," said study co-author Fiona Marshall, a zooarchaeologist at Washington University in St. Louis.
Today, every domestic cat in the world -- whether it's howling in a back alley, starring in a YouTube video or climbing into an empty box in your living room -- is descended from a single subspecies of Middle Eastern wildcat known as Felis silvestris lybica.
Marshall and her colleagues note the ancient village of Quanhucun, in central China's Shaanxi province, is far beyond F. s. lybica's natural range and raises the question of just how the cats got there. Were they imported from the Middle East as novelties, or even food? Were the Quanhucun kitties descended from an Asian subspecies of wildcat, Felis silvestris ornata, and later displaced or wiped out?
Marshall and her colleagues hope upcoming DNA analysis will clarify matters. In the meantime, experts have been left to wonder. "The question everyone has is, what cat is this and where did it come from?" said biologist and cat-lineage expert Carlos Driscoll, who is based at the National Institutes of Health and was not involved in the study. "The key ingredient that's missing here is DNA evidence."
The discovery reported in PNAS consisted of eight fossilized bones from at least two felines that were found in ancient trash pits along with other animal remains, pottery shards and tools. The bones in the pits accumulated over about 200 years, they wrote.
Researchers emphasized several factors that suggest the remains belonged to cats that had developed a unique relationship with long-ago farmers.
The bones are comparable in size to those of European house cats but smaller than those of European wildcats, they reported. A partial jawbone from one of the Quanhucun cats has very worn teeth, suggesting it was quite old and would have needed help to survive to such a ripe age, they added.
Other indications come in the form of isotope analysis. By examining the ratio of carbon and nitrogen isotopes in bone collagen, scientists can determine where an animal fell in the food chain and whether its diet consisted mostly of plants or of meat.
Tests showed one of the Chinese cats appeared to eat more millet than would be expected of a carnivore living in the wild, raising "the possibility that this cat was unable to hunt and scavenged for discarded human food or that it was looked after and fed by people," the study authors wrote.
-- Los Angeles Times