- Study: Dogs were domesticated between 18,800 and 32,100 years ago
- European hunter-gatherer cultures domesticated dogs, researchers say
- This contradicts other previously held theories
Every dog has its day, and scientists are trying to figure out when that first day happened.
At some point in ancient history humans developed close relationships with four-legged creatures that would have otherwise been wild, fierce wolves.
A new study in the journal Science argues that the domestication of dogs happened between 18,800 and 32,100 years ago in Europe. They say European hunter-gatherer cultures were responsible for turning lupine foes into best friends, long before humans developed agriculture.
It's a conclusion that barks up a controversial tree. The study goes against the idea wolves were domesticated when they wandered over to human agricultural settlements, lured by food. The study also contradicts previous research suggesting that dog domestication may have first happened in the Middle East or East Asia.
"There were many aspects in this study that we didn't expect," said Olaf Thalmann, researcher at Finland's University of Turku, who led the study. Chief among the surprises: the European origin of dog domestication.
Digging up bones
Seeking to sniff out when and where domesticated dogs emerged, scientists turned to genetics.
Researchers extracted and sequenced mitochondrial DNA. Mitochondria are structures in cells that convert food energy into usable forms. When working with these ancient samples, scientists focused on mitochondrial DNA because it is more prevalent in cells than DNA within a cell's nucleus.
Scientists recovered DNA fragments from the genomes of 18 prehistoric dog and wolf-like carnivores and 20 modern wolves with origins in Eurasia and America. Researchers compared these mitochondrial genome sequences with those of 49 wolves, 77 modern dogs, 3 Chinese indigenous dogs and 4 coyotes.
By highlighting similarities in DNA sequences among all of these specimens, researchers put together trees of close relationships called "clades." The more similar two creatures' sequences are, the closer together they will be in the clade.
Researchers organized the sp