An international group of scientists, led by the Francis Crick Institute, have found that the ancestry of dogs can be traced to at least two populations of ancient wolves. Dogs are known to have originated from the gray wolf, with this domestication occurring during the Ice Age, at least 15,000 years ago.
In a study (Nature), the researchers turned to ancient wolf genomes to further understanding of where the first dogs evolved from wolves. They analysed 72 ancient wolf genomes, spanning the last 100,000 years, from Europe, Siberia and North America.
The remains came from previously excavated ancient wolves, with archaeologists from 38 institutions in 16 different countries contributing to the study. The remains included a full, perfectly preserved head from a Siberian wolf that lived 32,000 years ago. Nine different ancient DNA labs then collaborated on generating DNA sequence data from the wolves.
By analysing the genomes, the researchers found that both early and modern dogs are more genetically similar to ancient wolves in Asia than those in Europe, suggesting a domestication somewhere in the east.
However, they also found evidence that two separate populations of wolves contributed DNA to dogs. Early dogs from north-eastern Europe, Siberia and the Americas appear to have a single, shared origin from the eastern source. But early dogs from the Middle East, Africa and southern Europe appear to have some ancestry from another source related to wolves in the Middle East, in addition to the eastern source, says a release.
One possible explanation for this dual ancestry is that wolves underwent domestication more than once. Another possibility is that domestication happened only once, and that the dual ancestry is due to these early dogs then mixing with wild wolves. It is not currently possible to determine which of these two scenarios occurred.
