A、Hunting and protection. B、Chasing prey. C、Herding livestock. D、Keeping accompany. D最初驯养狗的目的那部分内容比较有难度。原文用较快的语速回顾猜测了种种目的。现代人较为熟

It’s not known exactly bow or why humans domesticated the first dogs. But once tamed, people found them useful and they learned how to selectively breed for certain traits to create animals fit for specific task. Most likely, the first dogs were used for hunting and protection. Some were bred to chase down prey, others to herd livestock. Today’s most popular breed, the Labrador, was originally bred by fishermen to haul nets and retrieve fish. But at some point, humans also started to breed dogs for looks and for companionship. Brian has wondered why of all domesticated animals, dogs seem closest to their owners.
    Somehow during the long relationship together, dogs learn how to communicate with humans. And they pass the skill down to each succeeding generation. It turns out puppies can understand human gestures even if they’ve been raised in the wild, while wolves raised in captivity just don’t get it. It’s a unique skill that perhaps only dogs possess.