Can animals count?
动物能数数吗？
People count easily, from the time we are little kids and learn our one-two-threes.
数数对人类而言易如反掌，孩提时代就开始数一二三了。
But what about other species?
但是其它物种如何呢？
Careful observations in the wild support the idea that some can.
通过对于自然环境中一些物种的仔细观察发现它们真的具有这项技能。
The American coot is a duck-like North American bird.
美洲骨顶是一种生活在北美而且长得像野鸭的鸟类。
Sometimes a coot will try and sneak one of its eggs into a neighbor's nest.
有时骨顶会试着把自己的蛋偷偷放到邻居的巢中。
Some coots recognize the deception, and roll the stranger's egg out again.
有的骨顶能识破诡计，剔除这个不明来路的蛋。
Others don't catch on, and raise the stranger's egg as their own.
而有的则丈二和尚摸不着头脑，干脆当作自己的后代抚养长大。
Researcher Bruce Lyon at the University of California, Santa Cruz, and his team observed a series of coot nests for four seasons, noting which birds could spot a stranger's eggs and which couldn't.
加利福利亚圣克鲁斯大学研究员的布鲁斯·里昂和他的团队四个季节以来一直致力于观察骨顶巢。他们记录下了哪些鸟能认出陌生的鸟蛋，哪些不能认出。
Then they compared how many eggs each kind laid.
然后他们比较了这些鸟各生了多少蛋。
