Scientists Figure Out How Many Wild Birds Live on The Planet
首次全球鸟类“人口普查”：比人类多多了
Earth is home to around 50 billion wild birds according to a new global estimate, but most species are very rare and only a handful number in the billions.
据一项新的全球估算，地球是约500亿野生鸟类的家园。但大多数（鸟的）种类都极为稀有，数量屈指可数。
