Researchers have discovered the first living evidence of the so-called 'New World Dog' after creating the largest evolutionary tree of canines to date.
The ancient canine sub-species migrated across the Bering Strait with the ancestors of Native Americans and has previously only been identified using archaeological evidence. While most popular breeds in America are of European descent, the study found evidence that some modern canines from Central and South America – including the Peruvian Hairless Dog and the Xoloitzcuintle – are likely descended from the New World Dog.
The researchers constructed the evolutionary map using the gene sequences from 161 modern breeds of dog with the dataset totalling 1,346 individual dogs.
"What we noticed is that there are groups of American dogs that separated somewhat from the European breeds," explained study co-author Heidi Parker from the National Institutes of Health (NIH) biomedical research facility. "We've been looking for some kind of signature of the New World Dog, and these dogs have New World Dogs hidden in their genome."
The researchers haven't, yet, pinpointed which genes in modern hairless dogs are from Europe and which are from their New World ancestors but they intend to look at this in future research. The study could additionally help identify disease-causing genes in both dogs and humans.
Elsewhere, the research (published in the journal Cell Reports, highlights how the oldest dog breeds evolved, or were bred to fill certain roles.
For example, gun dogs, such as Golden Retrievers, can trace their origins to Victorian England where new technologies, including guns with longer ranges, made them useful on hunting expeditions. These dogs clustered closely together on the evolutionary tree, as did spaniel breeds.
Middle Eastern breeds, such as the Saluki, and Asia breeds, such as Chow Chows and Akitas, appear to have diverged well before the 'Victorian Explosion' of breeds in Europe and the US. The researchers also found that herding breeds, though largely European in origin, proved to be surprisingly diverse.
"When we were looking at herding breeds, we saw much more diversity, where there was a particular group of herding breeds that seemed to come out of the United Kingdom, a particular group that came out of northern Europe, and a different group that came out of southern Europe," said Parker, "which shows herding is not a recent thing. People were using dogs as workers thousands of years ago, not just hundreds of years ago."
The researchers have spent years sequencing dog genomes, often attending dog shows where they recruit owners to participate. All of the canine sequences included in the study are from dogs whose owners volunteered. More than half of dog breeds in the world today – of which there are nearly 400 – still have not been sequenced and the researchers aim to keep collecting dog genomes to fill in the blanks.
This article was originally published by WIRED UK
