Among the other findings, Dr. Larson that he found it particularly intriguing that once dogs had been domesticated, and even while sometimes breeding with wolves, no new wolf DNA entered their genomes.
In contrast, pigs, for example, were brought to Europe by farmers from Anatolia. But the genes from the first domestic pigs have been completely lost, replaced by the genes from wild European boars, although the pigs remained domestic animals.
While dogs cross each other, no new wolf genes survive over the years. One possibility, said Dr. Larson, is that “wolfness” just does not suit an animal as close to humans as a dog. Pigs can be a little wild, but “if you̵
Dr. Skoglund said that another exciting and inexplicable finding from the genome data was how fast dogs spread across the globe and diversified, so that 11,000 years ago there were not only five different genera, but some fossil DNA also showed that these genera had begun to combine again.
“How did it happen?” he said. “In ancient humans, we do not really know of any human expansion that would have made it easier on the order of 15-30,000 years ago.”
For the past 11,000 years, he said, dog genomes have shown evidence similar to that in human genomes from Anatolian farmers moving into Europe. But then there was the sudden loss of diversity in dogs that started about 4,000 years ago.
Also migrations from the steppes changed human genomes in Europe, but had almost no effect on the dog’s genomes. Conversely, migrations from the steppes to the east left an imprint on the dog’s genomic history, but not on humans.