Carolina dogs typically go into heat once a year, like wolves, instead of twice, like domesticated dogs. They cover up their scat by pushing dirt over it with their noses, not by using their hindquarters to scratch the ground.

Still, determining just what is and is not a Carolina dog requires a kind of gut instinct. To Mr. Anderson, it’s a matter of “I know it when I see it”; Dr. Brisbin is more blunt.

“The Carolina dog is a breed created by Brisbin,” he said, referring to himself in the third person, “by picking dogs he likes, the type that he thinks typify the ancient dog.”

This is not to say the Carolina dog is more mythic than real. But the problem is that some of the wilder dogs have mated with other breeds — local dogs and even coyotes. Determining just what is a Carolina dog means becoming more finely tuned to the sense that anyone feels stepping into Don Anderson’s enclosed acre. Experiential knowledge is crucial, being able to sense the entirety of the animal and in that way recognize which dog is almost purely Carolina and which is more of a mix.

Most Carolina dogs are ginger-colored, like Australian dingoes, but they can also be black and piebald. Most, but not all, are short-haired.

Some have tiny patches, right above their distinctive almond eyes, that look like a spare set of eyes, what Mr. Anderson calls “spirit eyes.” Some have an unusual white stripe at the shoulder. There are the noticeable ears and the tail, but also the athletic tucked-in stomach (like a Doberman). DNA studies may soon make it easier to assert the Carolina’s distinctions from other dogs.

Early Sightings

Awareness of this unusual dog has its own history. According to Mark Eden, another enthusiast working with Mr. Anderson, the journals of the 16th-century Spanish explorer Hernando de Soto include possible references to Carolina dogs.