One third of spider monkeys never make it to adulthood. 三分之一的蜘蛛猴都活不到成年

30. With long limbs and a prehensile tail that can grip like a hand,
    修长的四肢加上灵活如手的卷尾
31. they're built for climbing.
    他们就是为攀爬而生的
32. But imagine having to learn these skills as high up as this.
    但是要在这么高的地方学习这些技巧
33. One third of spider monkeys never make it to adulthood.
    三分之一的蜘蛛猴都活不到成年
34. This youngster is only a few months old.
    这只幼崽只有几个月大
35. Her future depends on her ability to climb.
    她的未来取决于她的攀爬能力
36. Playing on a practice tree with her older brother and sister,
    通过和哥哥姐姐在练习树上玩耍

来自《行星地球 第二季 第三集 Planet Earth S02E03 丛林》第 33 行