How dogs became man's best friend
Ancienthumans made dogs their best friend not once but twice, by domesticating twoseparate populations of wolves thousands of miles apart in Europe and Asia.
That is the conclusion of scientists who said on Thursday they had used modern geneticsto unravel canine evolutionary history, revealing a deep internal split betweendogs from opposite ends of the Eurasian continent.
that is the conclusion为主干部分，
fromopposite ends of 截然相反的
"Ourdata suggests that dogs were domesticated twice, on both sides of the OldWorld,"
"This suggests that at least two groups of humans independently came to the sameconclusion: dogs can be domesticated. It also suggests that the process of domestication, while mostly rare, may be replicated more often than we think."
come toconclusion: 得出结论
At somepoint in prehistory, they believe the eastern dogs dispersed with humanmigrants and replaced most of the western ones, so Asian ancestry is now dominantin modern dogs.
Although it is possible there was only one domestication event in Asia, followed byearly transportation to Europe, the research team argues the lack of archaeological evidence for dogs in the middle of the continent makes this very unlikely.
句子主干为the research team argues +从句
从句主干结构：the lack makes this very unlikely .
而of archaeological evidence 修饰lack， for dogs 修饰evidence，in 引导的介词短语修饰dogs。
What remains unclear is how grey wolves started down the long road that has ended up with today's kaleidoscope of dog breeds from Afghan hounds to Yorkshireterriers.
The idea that it began with a hunter-gatherer picking up a wolf pup and breedingtamer and tamer offspring is probably too simple, according to Greger Larson, agenetics expert in Oxford's archaeology department.
tamerand tamer 越来越驯化的
It'slikely to have been co-evolution. At first a pack of wolves got close tohumans, then humans got used to the wolves and, finally, there would have beensomething more intentional on the part of people.