Dogs may not have been man's best friend for as long as we thought they were.

A new 3D fossil analysis suggests dogs were first domesticated about 15,000 years ago, instead of during the late Paleolithic 30,000 years ago as was previously believed, Skidmore College reported. The findings suggest humans did not start domesticating dogs when they were hunter-gatherers, but rather had already taken up farming by the time the practice came about.

To make their findings the researchers created a method for measuring canid skulls found in Russia and Belgium that had been thought to prove dogs were domesticated during the late Paleolithic. The study revealed these fossils that were thought to be dogs were actually wild wolves by comparing their structures to modern and ancient wolves and dogs from North America and Europe.

"Scientists have been eager to put a collar on the earliest domesticated dog. Unfortunately their analyses weren't sensitive enough to accurately determine the identity of these fossils. The difference between a German shepherd skull and a wolf skull is subtle - you need to measure it in 3D to reliably tell which is which - and the same is true for these fossils," said Abby Grace Drake, visiting assistant professor of biology at Skidmore.

The study included 3D interactive figures and skull scans that helped distinguish domestic dogs from wild wolves.

"The difference between a wolf and a dog is largely about the angle of the orbits: in dogs the eyes are oriented forward, and a pronounced angle, called the stop, exists between the forehead and the muzzle. We could tell that the Paleolithic fossils do not have this feature and are clearly wolves," said Michael Coquerelle of the University Rey Juan Carlos .

The study's results are believed to be the most accurate on the subject to date. The researchers believe dog domestication occurred during the Neolithic when wild canines started to scavenge near human settlements.

"People are inherently interested in dogs and we have influenced their evolution," Drake said. "They are such a part of our lives. Knowing when domestication of dogs took place in the course of human history is important to our story and to theirs."

The findings were published in a recent edition of the journal Nature.