Ever wondered where man's best friend originated? Researchers have recently solved a long-time mystery of where wolves were domesticated first, saying that dogs originated independently from two different places.

According to Smithsonian, a University of Oxford study published in the Science journal and funded by the European Research Council and the Natural Environment Research Council, dogs originated from wolf populations that are living in West and East Eurasia.

The researchers were able to identify the dog's origin by comparing genetic data with a key archeological piece -- a 4,800-year-old bone from a medium dog discovered at the Neolithic Passage Tomb of Newgrange, Ireland. The team then sequenced the genome of the said fossil and collected data of mitochondrial DNA from 59 ancient dogs living between 14,000 to 3,000 years ago. These were then cross-checked and compared with the 2,500 modern dogs.

“The Newgrange dog bone had the best preserved ancient DNA we have ever encountered, giving us prehistoric genome of rare high quality. It is not just a postcard from the past, [but] rather a full package special delivery," said Senior author Dan Bradley from Trinity College Dublin.

Dublin further discussed that gene reconstruction using modern DNA is painstaking as he has no idea if crucial parts in the sequence have gone, Gizmodo notes. The researchers found out that there was a difference between the dogs living in the East and West. They also explained that Eastern dogs spread to Europe and bred with other dogs.

“Reconstructing the past from modern DNA is a bit like looking into the history books: you never know whether crucial parts have been erased,” said lead author Laurent Frantz.

Present day dogs are a hybrid of eastern and western dogs, which explains why scientists had a hard time identifying their origin through DNA.

Scientists say that the recent discovery, though astonishing, needs more evidence. The researchers are hoping to establish a clear timeline by combining ancient and modern genetic data through physical analysis and research.