A new study, which includes genetic analysis of hundreds of American dog breeds, has revealed Chihuahua's ancient roots trace back to Asia and not Europe, as previously believed.
"It was especially exciting to find that the Mexican breed, Chihuahua, shared a DNA type uniquely with Mexican pre-Columbian samples," said Peter Savolainen, a researcher in evolutionary genetics. "This gives conclusive evidence for the Mexican ancestry of the Chihuahua. Most people thought they were just runaway European dogs."
Swedish researchers with the KTH Royal Institute of Technology in Stockholm now believe that these little canines hitched a ride from Asia to the Americas with ancient humans.
It has always been assumed that the arrival of Europeans in the Americans led to the extinction of indigenous dog breeds, but this comprehensive genetic study found that the original population of native American dogs has been almost completely preserved.
Savolainen said the study found 30 percent or less of native American dog breeds’ DNA comes from Europe, which suggests that canines on the North American continent originally traveled to the Americas long before with the ancient humans who established pre-Columbian civilizations.
Most researchers believe the first American settlers from Asia brought dogs with them across the Bering Strait about 10,000 years ago. This includes the hairless Peruvian dogs, which appear to be the predecessors of the currently popular little Chihuahua, which we associate with Mexico, the Daily Mail reports.
As recently as the 16th century, European colonizers brought their own dog breeds to the Americas, as well as a myriad of deadly human and canine diseases,
"Many populations were wiped out and their culture disappeared with them, so there was nobody to take care of the dogs," Savolainen said.
Thus, many scientists thought that most American dog breeds shared most of their DNA with the surviving European breeds. However, during this study early native American dogs from Asia that were thought to be extinct have been found to be thriving, according to the Swedish researchers.
Genetic analysis of hundreds of American dog breeds including Chihuahuas, sled dogs and hairless Peruvian dogs has revealed that their ancient roots trace back to Asia.
HOW THE STUDY WAS DONE
To trace the roots of American dog breeds, Savolainen's research group worked in cooperation with colleagues in Portugal. They compared DNA from Asian and European dogs, ancient American archaeological samples and American dog breeds, including Chihuahuas, Peruvian hairless dogs and Arctic sled dogs.
They collected cheek swabs from 347 kennel club pure breeds from the Americas, including Chihuahuas, Peruvian hairless dog and Alaskan malamutes and then compared their DNA with 1,872 sampled from dogs in Asia and Europe. The research, which was published in the journal Proceedings of the Royal Society B, found that most of the American dogs had ancestry that can be traced to Asia.
The team also tested 19 stray dogs from the Carolinas and South America. Savolainen believes that the data also suggests that the stray dogs carry genetic markers from Asia, not Europe.
Source: Daily Mail