(AP) -- Mexican researchers said Wednesday they have identified jaw bones found in the pre-Hispanic ruins of Teotihuacan as those of wolf-dogs that were apparently crossbred as a symbol of the city's warriors.

The National Institute of Anthropology and History said the jaw bones were found during excavations in 2004 and are the first physical evidence of what appears to be intentional crossbreeding in ancient Mexican cultures.

The jaw bones were found in a warrior's burial at a Teotihuacan pyramid. Anthropological studies performed at Mexico's National Autonomous University indicate the animal was a wolf-dog.

"In oral traditions and old chronicles, dog-like animals appear with symbols of power or divinity," said institute spokesman Francisco De Anda. "But we did not have skeletal evidence ... this is the first time we have proof."

Wolf- or dog-like creatures appear in paintings at Teotihuacan, but had long been thought to be depictions of coyotes, which also inhabit the region. But archaeologists are now re-evaluating that interpretation.

Several jaw bones were made into a sort of decorative garment found on the warrior's skeleton at the 2,000-year-old site north of Mexico City.

The wolf-dog apparently served as a symbol of strength and power.

Dogs and wolves are very similar genetically, and there has been evidence of ancient remains that may show natural crossbreeding.

But archaeologist Raul Valadez said the animal was the result of intentional selection. While the inhabitants of Teotihuacan had dogs, wolves and coyotes, they almost exclusively used wolf-dog bones in the ceremonial arrangement.

Of the bones found, eight were wolf-dog, three were dogs and two were crosses of coyotes and wolf-dogs.

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