In northwestern Saudi Arabia, a hunter surrounded by a pack of dogs threads an arrow, props it up against the string of his bow, and pulls it back to kill a wild animal roaming nearby. He's flanked by other hunters readying their weapons.

This scene, and others like it, are engraved onto the cliffsides protruding from the dry, arid desert covering the northern region of present-day Saudi Arabia. A team of researchers think it may be the earliest depiction of dogs ever documented—although other experts aren't yet convinced of that fact. (This story was first reported by David Grimm for Science.)

"The distinction of herders and hunters was immediately clear," said Maria Guagnin, an archaeologist from the Max Planck Institute for the Science of Human History in Germany. Working with the Saudi Commission for Tourism and National Heritage, Guagnin documented 1,405 rock art panels that contain 6,618 individual animal depictions.

Rock art carved into the cliffsides of archaeological sites at Shuwaymis and Jubbah shows images of dogs aiding human hunters. Compared to the adjacent carvings of people, the canines are medium-sized, with short snouts, pointed ears, and a perky, curled tail. They resemble the modern-day Canaan dog breed.

The rock art has an intriguing detail that shows an early effort to use dogs as hunting partners. What appear to be leashes tether the dogs to their human companions. Extending from the dogs' necks, rope-like lines run to human waists. In one scene, the image of a human is shown poised to use a bow to shoot an arrow, with tethered dogs flanking his sides. (Learn why dogs are so friendly.)

Oldest Images of Dogs

"The problem with engravings is there is no reliable method to date them directly," explained Guagnin. To reach a rough estimate, researchers analyzed the weathered rock surrounding the site, and the contents of what's depicted in the engravings.

The rock art scenes include sheep and cattle, indicating a pastoral society was present when the dogs were carved. Pastoralism is thought to have emerged on the Arabian Peninsula during the early half of the sixth millennium, and Guagnin says her most conservative estimates of the carvings date from this time period.

Dogs: (Prehistoric) Man's Best Friend

She highly suspects, however, that the carvings were made during the mid-ninth or eighth millennium BC. More evidence would be needed to more conclusively date the rock art, but if Guagnin and her team can prove their hunch that the art dates back to 9,000 or 8,000 B.C., it could possibly show the world's first images of dogs. Her findings were recently published in the Journal of Anthropological Archaeology.

"It's like a graphic novel," said Melinda Zeder, an archaeozoologist from the Smithsonian Institute's National Museum of Natural History who was not involved in the research. "These images put flesh on the bones."

She speculated that the Arabian Desert cave art could be as old as 5,000 B.C., when physical evidence of pastoralism was first documented. Saying the scenes are older than that is too speculative, she said.

Zeder described other evidence of dogs in Syrian rock art in a 2013 study. Those images showed dogs being used to aid large-scale hunts, and nearby bones led her to date those images to the 4th millennium.

Ancient Pets

Archaeologists have long known that dogs were domesticated during the Neolithic period. Dog bones dating back roughly ten thousand years have been found near human settlements, said Zeder. Evidence that dogs aided hunting missions has been less immediately obvious.

Robert Losey, a professor at the University of Alberta, is an expert on ancient relationships between humans and animals, particularly with dogs. He's found evidence of 10,000-year-old dog remains in Siberia, but he is unsure of the exact role these dogs played. The remains, he said, were deliberately buried, with the skeletons fully intact—meaning they likely wouldn't have been a food source.

"There's been ethnographic work showing being aided by dogs greatly improved the productivity of hunting," he said. His hunch is that dog domestication coincided with, or was aided by, humans who benefitted from hunting with the amiable canines. He thinks it's plausible that the art does show the dogs being led on leashes.

"The emotional attachments people have to dogs are very, very old," he said. (Learn more about how dogs may have domesticated us.)

Guagnin noted in her study that the level of detail used to depict the dogs indicates the artist or artists may have had a close bond with the animals.

While Zeder is skeptical of Guagnin's claims of how old the carvings are, she agrees that the artistry shows those strong bonds.

"What strikes me about the rock art is the degree of detail. The different markings of the dogs, the common shoulder stripe, the white spots. The level of artistic reality and detail is really remarkable," said Zeder.