Don:Time to go again to the A Moment of Sciencemailbag. A listener writers: Dear Yael and Don: Whyis it that whenever I see someone looking atsomething, like someone gazing up at the sky, I lookthere too? Is it just me, or do we all do this?

唐：又到了科学一刻读信时间了。 一位听众写道：亲爱的雅艾尔和唐，每当我看见别人在看某件事物时，比如说望向天空，我也会朝那个方向看，这是为什么呢?只有我是这样，还是大家都这样做?

Yael:Great question! And the answer is that whatscientists call gaze-following is pretty much auniversal human trait. We're all prone to follow another person's gaze even if we're not surewhat they're looking at, or why.

雅艾尔：这个问题问得好!科学家称这种现象为视线追随，几乎全人类所共有的特征。我们都倾向于跟随别人的目光，即使不知道他们在看什么，或者为什么看。

Don:Right. But why do we gaze-follow? British researchers think it dates back to our primitiveprimate ancestors, who may have evolved the behavior as a way to locate food. When theBritish scientists studied gaze-following in lemurs, which are very primitive primates, theyfound that lemurs do in fact use gaze-following as a strategy to locate areas likely to containfood. When a lemur sees one or more of its fellows looking in a particular direction, it will turnits attention that way, too. And at some point the lemur is likely to search that area for hiddenfood.

唐：对。但是我们为什么会追随别人的目光?英国研究人员认为，这种行为可以追朔到我们的灵长类祖先，这是进化的结果，灵长类动物把这当做寻找食物的一种方式。当英国科学家用狐猴做实验时，发现狐猴实际上是利用目光追随来定位有食物的区域。当一个狐猴看见一只或者一群同胞正看向特定的方向时，也会将注意力集中到那个方向。而且在大多情况下，狐猴很有可能在那片区域找到潜在的食物。

Yael:Of course, gaze-following could also be a way of sensing danger and staying away from acertain place. In any case, the point is that our human tendency to gaze-follow could haveancient origins. We no longer follow gazes for foraging purposes. But it's still useful as a way ofbeing alerted to something interesting, or menacing, in the vicinity.

雅艾尔：当然，目光追随也是一种感知危险，远离某个场所的方式。在任何情况下，人类这种追随别人目光的倾向很可能源自古时，这点值得一提。虽然我们不再以觅食的目的，但目光追随仍然可以用来发现身边的趣事或者危险。