The mammal's intelligence is his only defense... 哺乳动物的智慧是它唯一的防御手段

282. His time down here is limited by how long he can hold his breath.
     它在水下的时间 受限于它能屏住呼吸的时间
283. He seems caught between two worlds,
     它似乎夹在两个世界之间
284. especially when facing danger.
     尤其是面临危险的时候
285. The mammal's intelligence is his only defense...
     哺乳动物的智慧是它唯一的防御手段
286. but he can't stay down here forever.
     但它不可能永远躲在下面
287. Otodus.
     耳齿鲨
288. Twice the length of a great white shark.
     身长是大白鲨的两倍

来自《我们星球上的生命 第一季 第七集 Life on Our Planet S01E07 地球继承者》第 285 行