but it contains more than 50 percent of all its plants and animals. 但其中的动植物种类却占到了全球的50%

167. That is why the jungle grows so vigourously
     因此 这里的丛林茂密葱郁
168. and supports so much life.
     生命在此欣欣向荣
169. This forest covers only 3 percent of the planet's surface,
     这些森林仅覆盖了地球表面的3%
170. but it contains more than 50 percent of all its plants and animals.
     但其中的动植物种类却占到了全球的50%
171. The canopy is particularly rich.
     树冠层是生命最繁荣的地方
172. There are monkeys, birds
     这里有猴子、鸟
173. and millions of species of insects,
     还有数百万种昆虫

来自《行星地球 第一季 第一集 Planet Earth S01E01 从北极到南极》第 170 行