A study published last month details one of the most diverse canine genome maps produced to date tracing the relationship between breeds. In examining the genomes of over 1,000 dogs, the map provided insight into two interesting findings.
The first showed that canines bred to perform similar functions, such as dogs from the herding or working groups, don’t necessarily share the same origins.
Herding breeds are my favorite, holding beloved traits like intelligence and agility. So it’s surprising that these dogs may be more different than they seem.
The reason behind this convergence may also be why geneticists had difficulty mapping out herding dog lineages in the past. Study author Elaine Ostranger believes this happened because herding dogs emerged through selective breeding at multiple times in many different places.
“In retrospect, that makes sense,” says Elaine. “What qualities you’d want in a dog that herds bison are different from mountain goats, which are different from sheep, and so on.”
The second finding shed light on an ancient type of dog that may have come to the Americas thousands of years before Christopher Columbus. Researchers have looked for the genetic legacy of these dogs in the DNA of modern American breeds, but have found little evidence until now.
Most of the breeds studied originated in Europe and Asia. But domestic dogs first came to the Americas thousands of years ago, when people crossed the Bering land bridge linking Alaska and Siberia. These “New World dogs” later disappeared when European and Asian dogs arrived in the Americas.
But the way two South American breeds, the Peruvian hairless dog and the xoloitzcuintli, are clustered together on the map suggest they could share genes not found in any of the others. This means those genes could have come from dogs that were present in the Americas pre-Columbus.
“I think our view of the formation of modern dog breeds has historically been one-dimensional,” says Bob Wayne, an evolutionary biologist at the University of California. “We didn’t consider that the process has a deep historical legacy.”
Researchers now think that dog breeds underwent two major periods of diversification. Thousands of years ago, dogs were selected for their skills. This changed a few hundred years ago, when animals were bred for physical traits instead.
Bob says that, when it comes to genetics, studying dogs is a unique opportunity since no other animal has had the same level of intense deliberate breeding.
While it’s interesting to learn more about our dogs and where they came from, the scientists had practical reasons for creating this genetic database. They hope that this information can help future studies of canine and human diseases.