Dogs (Photo : Reuters/Nacho Doce)
According to the largest DNA study to date on the origin of dogs, the first dogs were domesticated about 15,000 years ago in Central Asia, near present-day Nepal, India, and Mongolia.
The study, headed by Adam Boyko of Cornell University in Ithaca, New York, claimed that Central-Asian hunter-gatherers domesticated grey wolves when human population density, climate change, and advanced hunting methods, reduced the availability of prey. Pushed to scavenging, the animals became tamer and smaller, reducing their hunting prowess and leading them to domestication.
Boyko's team analyzed genetic markers in blood samples extracted from canines in 38 countries across six continents.
"This is the first global study of genomic patterns of dog diversity," says Boyko.
Fronted by postdoc Laura Shannon, the group of scientist traveled the world for seven years to collect DNA samples from thousands of village dogs, including strays and unleashed hounds, which are better sources of an authentic genetic signature of original dog populations than modern-day purebred dogs, whose genetic line only goes back 200 years or so.
"They are very different from pure-bred dogs genetically because they are free-breeding, so in a genetic sense, they are a natural population," Boyko says.
Unfortunately, a few researchers were bitten during the course of the project, The Atlantic reported.
The study, published in the website of Proceedings of the National Academy of Sciences of the United States of America (PNAS) contradicts earlier findings that Dogs have evolved from Eurasian gray wolves in Europe between 32,000 and 18,000 years ago.
There are also proposals that canines originated in Siberia, the Middle East and southern China. Lastly, there's a claim that its begun in East Asia about 32,000 years ago.
While Boyko acknowledges his study by itself is not likely to end the debate, Oxford University's Greger Larson said Boyko's study was a major step forward.
Nonetheless, Larson questioned whether using DNA from modern-day dogs can reveal the true origins of dogs. He also noted that almost every geographical region on Earth has at least one study presenting it as a candidate for the domestication of dogs.
