DK新版Complete Dog breed book choose the perfect dog for you new edition完整的狗品种书籍为您选择完美的狗
WHAT IS A DOG? The evolution of the dog from wild predator to domestic companion has been greatly influenced by human intervention.
It has taken just a few hundred years to produce seemingly endless variations on the canine theme –
but planned breeding has not removed the basic characteristics of the dog’s ancestor, the wolf
Evolution of the dog All dogs share a common ancestor: the grey wolf. While this relationship is fairly apparent in breeds such as the German Shepherd or Spitz-type dogs,
with their wolf-like heads and pricked ears, it is hard to see the connection between wolves and Toy Poodles or St. Bernards. Genetically, however,
any dog of any breed is virtually identical to the wolf. The transition from wolf to the huge diversity of domestic dogs known today happened relatively quickly. The process began gradually,
with random changes in size and shape, but accelerated when humans began to selectively breed those dogs that exhibited characteristics they desired
In from the wild Grey wolves and dogs diverged between 15,000 to 40,000 years ago, but when and where they developed a close relationship with humans is unclear.
DNA evidence for domesticated dogs has been found in several locations in Asia and Europe; the timing varies from 20,000 to 40,000 years ago, which suggests that domestication events may have occurred more than once,
and in different areas. The oldest remains known to be domesticated dogs date back to around 14,000 years ago, and comprise human-dog burials from the Middle East and Germany.
Older dog fossils from Europe and Asia also exist, but whether these are fossils of domesticated dogs remains uncertain.
There are alternative theories about how dogs became domesticated. Some scholars believe that wolves scavenging around early human encampments were killed for their meat and skin;
their orphan pups were taken in and reared in captivity, and were found to be valuable as hunters and protectors,
beginning the process of domestication. Others question why humans would want to domesticate a large predator that would compete with them for food. They sugges
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