For thousands of years, the line between wolves and dogs has been blurred. Groups of people in different parts of the world, independently of each other, have repeatedly tried to domesticate wild wolves. However, we can see the result of only one such attempt today. A recent study shows that even after dogs spread across Eurasia and the Americas, people in what is now Alaska interacted with a strange mix of dogs, wolves, wolf-dog hybrids, and some coyotes.
Archaeologist François Lano from the University of Arizona and his colleagues studied 111 sets of dog and wolf bones from archaeological sites in the interior of Alaska. The oldest bones belonged to wolves that roamed the area long before humans appeared, and the newest ones belonged to modern wild Alaskan wolves. The researchers worked with the remains of wolves, dogs, and even a few coyotes, covering the period from 1,000 to 14,000 years ago.
«The Late Pleistocene in Alaska was likely a period of experimentation in the relationship between humans and dogs», — Lano and his colleagues write.
People may have domesticated dogs that left no trace in modern dog lines. Or wild dogs may have been kept as pets, while others were used for hunting.
The scientists compared the animals’ DNA with modern dogs and wolves, as well as ancient wolf populations from Siberia. They also measured the ratio of nitrogen isotopes in the animals’ bones and teeth to determine their diet. Wolves don’t usually fish, so the presence of fish in their diet indicates that they received food from humans or ate leftovers.
Until 13,600 years ago, wolves living in what is now Alaska ate their traditional diet of hares, moose, and other land animals. But after this period, fish began to dominate the diet of some wolves, which probably reflects their interaction with humans.
At a site called Hollembeck Hill, archaeologists have found the remains of four canids, which are about 8,100 years old. Their diet consisted mostly of salmon, indicating possible domestication. But the DNA of these animals showed that they were closer to modern wolves than dogs. Some of them had the features of early dogs, while others looked like wolves or even hybrids.
All modern dogs are descended from the same group of wolves that lived in Siberia 23,000 years ago. But findings from Hollembeck Hill and another site, Swan Point, show that between 11,300 and 12,800 years ago, dogs had DNA that is not related to modern dogs. This may indicate that the process of domestication occurred multiple times in different places, but only one lineage survived to this day.
Even after «the invention of» dogs, people continued to repeat this process: they allowed the least aggressive wild canids to live nearby and possibly fed them, which contributed to new attempts at domestication.
Source: arstechnica