Carlos Solis
If you see a cute little puppy wandering down the street, keep in mind: there’s real wolf DNA inside it.
This revelation comes from researchers at the Smithsonian National Museum of Natural History. They were surprised to discover that about two-thirds of dogs from all breeds carry a certain amount of wolf DNA.
And this isn’t just a genetic remnant from that pivotal moment around 20,000 years ago when dogs diverged from wolves. Instead, the team says it suggests that domesticated dogs and wild wolves have been interbreeding over the last few thousand years.
“This doesn’t mean that wolves are coming into your home and ‘mixing’ with your pet dog,” says Logan Kistler, a museum curator and co-author of the new study.
Dogs and wolves can produce offspring, but interbreeding between them is believed to be rare.
“Until now, leading scientists assumed that for a dog to be considered a dog, it shouldn’t have a significant amount of wolf DNA,” noted lead author Audrey Lin.
What Did the Team Discover?
To delve deeper into this issue, scientists analyzed thousands of dog and wolf genomes from publicly available databases. They found that over 64 percent of modern breeds have wolf ancestry, with even tiny Chihuahuas carrying about 0.2 percent.
“This is completely understandable for those who own Chihuahuas,” Lin joked.
The breeds with the highest percentage of wolf DNA—around 40 percent—were the Czechoslovakian and Saarloos wolfdogs.
Among domestic breeds, the most “wolf-like” were the large Anglo-French tricolor hounds, which carry about five percent wolf DNA. A significant percentage was also found in greyhounds, according to Science Alert.
Anglo-French tricolor hounds
The study also found that every rural dog living in human settlements—but not kept as a pet—has wolf ancestry.
Kistler suggested that rural dogs, which have more opportunities to interact with wolves, could be the channel through which wolf DNA entered the dog gene pool. He believes that wolves driven away from their packs by human activities such as habitat destruction may begin to interbreed with stray dogs.
Genes and Personalities
Researchers compared the genomic data with kennel-club descriptions of each breed’s temperament.
Breeds with little or no wolf DNA were often described as friendly, affectionate, and easy to train.
By contrast, dogs with a high percentage of wolf DNA were typically wary of strangers and more independent.
The study’s authors say wolves evolved for specific habitats and conditions, while dogs have been spread by humans around the world. Dogs had to adapt to the places humans brought them, and in some environments wolf genes provided useful advantages, the authors wrote.
For example, many breeds from Tibet, such as the fluffy little Lhasa Apso, carry the EPAS1 gene, which arose from adaptation to high altitudes. Tibetan wolves have the same gene.
The findings of the study were published in the journal Proceedings of the National Academy of Sciences.
Photo: Unsplash
