But, when new challenges arrive, they can struggle to cope. 但当新挑战来袭 它们只能尽力去应对

261. Humans brought these ant invaders here,
     是人类把这些蚂蚁入侵者带上了岛
262. and now humans are having to control them.
     而现在人类不得不采取措施控制局面
263. Isolated communities may evolve for millions of years in relative peace,
     与世隔绝的动物群落 可能在数百万年内演化出了相对稳定的生态
264. But, when new challenges arrive, they can struggle to cope.
     但当新挑战来袭 它们只能尽力去应对
265. Of all the species that have become extinct in recent years,
     近年来濒于灭绝的物种之中
266. around 80% have been islanders.
     大约百分之八十是岛屿物种
267. Our impact on the Earth is greater today than ever before.
     人类对地球所造成的影响 比以往任何时候都要深远

来自《行星地球 第二季 第一集 Planet Earth S02E01 岛屿》第 264 行