Incredibly, the unhatched tadpoles can sense danger, 难以置信的是 未孵化的蝌蚪能感应到危险

230. The youngest eggs are the most vulnerable,
     刚产下的卵是最脆弱的
231. and he can't guard them all.
     他无法同时保护所有的卵
232. But these tadpoles are not as helpless as they might appear.
     但这些小蝌蚪并不像表面看起来那样无助
233. Incredibly, the unhatched tadpoles can sense danger,
     难以置信的是 未孵化的蝌蚪能感应到危险
234. and the oldest and strongest
     那些最成熟和最强壮的
235. wriggle free and drop into the stream below.
     可以扭动着挣脱出来 掉进下方的溪流里
236. The eggs at the top of the leaf, however,
     然而叶子顶部的卵

来自《行星地球 第二季 第三集 Planet Earth S02E03 丛林》第 233 行