时差N小时 蜣螂的秘密(下)（在线收听）

There are many dung beetles competing for a limited amount of food at a dung pile, so whenan individual is finished rolling a ball of dung it is in its best interest to make a quick escape.And the fastest way to travel is in a straight path. Scientists noticed that when the moon wasvisible, these dung beetles did just that; they traveled in straight paths. But when it was acloudy night, the beetles' paths became shaky and erratic.

屎壳郎之间食物的竞争很激烈，往往是很多只屎壳郎齐齐盯上一堆粪。因此，当一只屎壳郎滚好了一个粪球后最好就是尽快离开。当然，最快的就是走直线了。科学家们发现，在月明星稀的夜里，屎壳郎就是这样做的，它们都走直线。但是，如果是在乌云密布的夜里，无法看到月亮，这个时候的屎壳郎所走的路线就会歪歪扭扭。

To be sure the beetles were indeed using the moon's polarization and not the moon itself, theresearchers used a filter that changed the pattern of the polarized moonlight by 90 degrees.The beetles responded by changing their course by 90 degrees.

为了确定屎壳郎是凭借着月光的偏振作用而不是月光来看路，研究者们使用了一个滤光器，这个滤光器将月光的偏振改变了90度，这个时候他们发现，屎壳郎的路线也随之改变了90度。

Scientists suspect that the dung beetle isn't the only animal to navigate by the moon'spolarization and that more such creatures will soon be discovered.

科学家们还推测，屎壳郎并不是唯一一种凭借月光偏振作用为自己“导航”的动物，相信很快也会发现其它的此类生物。