许多人把狗狗当做宠物的原因之一就是认为狗能通人性，可为什么它们能懂得人类的想法呢?下面的新托福考试阅读练习资料也许能解答这个问题。
Point at a ball and a dog will look at the ball, whereas a cat will probably look at your hand. Dogs seem to have a ready understanding of how human beings direct attention by pointing, and can follow our gestures almost as if they thought the same way we do.
Of course, dogs probably aren’t born knowing anything about people. We just carefully train them to look, fetch, and so on, right? Or do we? A comparative psychologist at the Max Plank Institute in Germany,named Michael Tomasello ran a series of tests on dogs,in which they had to find which sealed container had yummy dog food in it. The only hint they got was from a human being who looked at or pointed at the right container. This wasn’t hard for dogs at all.
But it was hard for wolves. Wolves that have been raised by people should have had the same success at finding the sealed container, but they didn’t. Even chimpanzees, which are very smart animals indeed, weren’t as fast at finding the food as dogs. What does this mean?
One interpretation is that dogs do, in fact, have a natural ability to understand forms of human communication. Even nine-week old puppies found the food, suggesting the skill is there before training. Wolves don’t have the skill, suggesting that it has developed in dogs since the time they branched off from their evolutionary predecessors.
There is debate about this idea. But Tomasello thinks that in the past fifteen thousand years, as human beings and dogs have evolved together, the basis for fido’s ability to understand what you mean may have become encoded in his genes.
当人手指着球的时候，狗会看着球;而猫很可能看着手。似乎，狗能读懂人的指示并执行指示。狗和人类的思维方式好像是一致的。
当然，狗不可能天生就知道人的想法，都是受过精心的训练：看、拿……是不是?德国普朗克学院的比较心理学家Michael Tomasello对狗进行了一系列测试。他要求狗找出藏有美味食物的密封容器。而唯一的提示是人的眼神或指示。这项测试对狗而言是小菜一碟。
但是狼却做不到。本以为一直受人抚养的狼也能准确找出，可是，狼却失败了。甚至十分聪明的黑猩猩，也比不上狗的速度。为什么?
一种解释是狗确实天生理解人沟通的方式。甚至是9周大的小狗都能找到食物，说明这种能力并非后天受训。而狼却不具备这种能力，狗和狼虽有共同的祖先，但是由于进化而形成差异。
虽然这一观点备受争议，但是Tomasello认为，早在15000年前，人和狗都在进化过程中，那时，狗已经具备能力读懂人的想法并代代相传。
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