Researchers who analysed nearly 2,700 dog and wolf genomes say most modern dog breeds carry traces of wolf DNA, the result of interbreeding over the past few thousand years. Coverage from Cbsnews has highlighted this story.

The findings, published as a broad genomic analysis, show wolf ancestry sprinkled through the nuclear genomes of many breeds and tie that inheritance to traits such as body size and working ability. The researchers’ dataset included 264 modern dog samples within the genomes examined.

Logan Kistler of the Smithsonian National Museum of Natural History, a coauthor on the work, described the relationship between the species plainly: “Dogs are our buddies, but apparently wolves have been a big part of shaping them into the companions we know and love today,” he said. Reporting by Sciencedaily offers additional detail on this case.

Audrey Lin, an evolutionary biologist at the American Museum of Natural History, summed up the study’s central finding in a few terse words: “Wolf is there,” she said, noting that the signal appears across many modern lineages.

The genetic legacy is not uniform. Intentionally bred wolf–dog hybrids occupy the extreme end of the spectrum: the Czechoslovakian Wolfdog is a deliberate hybrid that retains high percentages of wolf ancestry, and the Saarloos Wolfdog is another deliberate hybrid. By contrast, some large, long-established breeds show little to no detectable wolf input. The Bullmastiff was described as genetically far from wolves.

Working and regional traditions also matter. Breeds developed near wolf populations or maintained as working lineages show elevated percentages of wolf ancestry in the genomes examined. The study highlighted examples of West and Central Asian guardian types that retain meaningful wolf admixture. As covered by Livescience, readers can explore more context around the event.

The research also drew attention to surprising examples at the opposite end of the scale. Chihuahuas registered an average of just 0.2 percent wolf DNA, a small but detectable trace that researchers said aligns with the broader pattern that most modern dogs are “a little bit wolfy.” “This completely makes sense to anyone who owns a Chihuahua,” Audrey Lin added.

Authors compiled genomes from published sources to build a broad, time-spanning picture of canid ancestry. The analysis points to interbreeding events within the last few thousand years as the primary source of the wolf signal in modern dogs, rather than solely ancient shared ancestry.

The work reframes how scientists understand the boundaries between domesticated dogs and their wild relatives: rather than genomes being strictly separated, many modern dogs carry measurable fragments of wolf DNA that appear to have persisted through selective breeding and regional practice.

Readers can find institutional summaries and coverage of the study at the Smithsonian Magazine and the American Museum of Natural History’s write-up, and a scientific summary is available through ScienceDaily.

Source

Original reporting: view the original article.