South America’s Patagonia region – essentially, the southern parts of Chile and Argentina – is home to a breed of dog called the Patagonian sheepdog. But as the Patagonian sheepdog is not a recognised breed by the world’s kennel clubs, little research into its origins has ever been carried out.
Now, though, a team of geneticists have used genotyping to determine how the Patagonian sheepdog breed came into being. Genotyping can be thought of as a kind of broad-stroke or low-resolution genetic sequencing: it’s a technique that will give you a useful overview of an individual’s DNA make-up as a whole, without having to go to the time, trouble or expense of sequencing each individual gene.
As reported in the journal PLOS Genetics, the researchers genotyped 159 individual Patagonian sheepdogs from Chile and Argentina, and compared their findings to published genetic data on 175 recognised domestic dog breeds and two species of wild dog. As a result of their labours, the researchers found out two things about the little-understood South American breed.
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Firstly, it’s not really one dog breed at all, but two. In the middle of the Patagonia region, high up in the Andes mountains, lie the Patagonian Ice Fields, and the team found that sheepdog populations to the north and south of this natural divide are genetically distinct from one another, with those to the north more closely related to Border collies, and those to the south more closely related to Australian kelpies.
They also discovered that the Patagonian sheepdog, which looks rather like an Old English sheepdog with its thick, shaggy coat, is actually more closely related to Border collies and Australian kelpies.
At first, this is surprising, but as the researchers pointed out, the Patagonia region was colonised by European settlers in the mid-late 1800s – before dog breeds had been ‘formalised’ by the Kennel Club, which led to ever more selective breeding, and to the huge variation seen between different dog breeds today. And as many of those settlers were sheep farmers who came originally from Scotland and Wales, it makes sense that they would have taken their collie dogs with them.
In fact, the researchers now believe that all modern sheepdogs share a common ancestor, as recently as 150-200 years ago. The Patagonian sheepdog, having undergone very little in the way of selective breeding, is probably the closest thing to that common ancestor or ‘foundational sheepdog’ still extant.
“Using a variety of genomic approaches, we ascertained the relationship between this dog population and modern herding breeds,” said one of the study’s authors Natasha Barrios, within the Faculty of Veterinary Sciences at the Universidad Austral de Chile.
“We propose that the Patagonian sheepdog is the closest living relative of the common ancestor of modern UK herding breeds. These findings, in turn, increase our understanding of human migratory events at the time.”
#Nature | https://sciencespies.com/nature/south-americas-patagonian-sheepdog-related-to-ancestor-of-all-modern-uk-herding-breeds/
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