A study in the United States of America reveals the amount of wolves present in dog breeds

Does that little dog crossing the sidewalk also have a wild streak? A new study conducted by American scientists indicates this. Approximately 64% of modern breeds have a detectable amount of wolf DNA, not inherited from distant ancestors, but the result of hybridization that occurred over the past few thousand years.

Understands: Study reveals that most dogs still carry wolf DNA (even gentle ones)

The findings, released on Monday (25) by researchers from the Smithsonian Institution’s National Museum of Natural History and the American Museum of Natural History, reignite the debate about how dogs and wolves continue to interact beyond domestication that began about 20,000 years ago.

The team analyzed thousands of dog and wolf genomes available in public databases. The survey showed that even Chihuahuas carry about 0.2% lupine DNA.

“Before this study, more advanced science seemed to indicate that for a dog to be considered a dog, there couldn’t be much, if any, wolf DNA,” said lead author Audrey Lin. Co-author Logan Kistler stressed that this does not indicate repeated encounters, but rather rare episodes with lasting consequences.

Czechoslovakian wolfhounds and Saarlos led the way with up to 40% wolf DNA. Among pet breeds, the Grand Anglo-Français Tricolore came out on top, at approximately 5%.

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Sight-hunting breeds, such as the Saluki and Afghan, also recorded high rates. Size is not decisive: for example, Saint Bernards did not appear large in origin.

The study also showed that 100% of “village dogs” – living close to human communities, but without an owner – carry wolf heritage. The authors suggest that it may serve as a contemporary gateway to this genetic admixture.

Effects on behavior

The researchers compared genetic data with temperament descriptions used by breed clubs. Breeds with small wolf origins tend to be considered friendly and easy to train.

Those with a higher percentage of wolf DNA are often described as independent, territorial, or suspicious of strangers. However, Kistler cautioned that these categories do not determine individual behavior.

He explained that “wolves evolved into specific environments, while dogs were transported to all parts of the world inhabited by humans.”

Certain genetic traits appear to offer advantages. Tibetan breeds, such as the Lhasa Apso, carry the EPAS1 gene, which is linked to adaptation to high altitudes, the same gene found in wolves in the region.

The study published in the Proceedings of the National Academy of Sciences suggests that environmental changes, such as habitat fragmentation, may have made isolated female wolves closer to feral dogs.

This interaction, according to the authors, would help explain how part of current canine diversity has received recent contributions from the wolf genome.