translation.en: Video: Kanzi now makes his tools, just as our ancestors may have made them, two-and-a-half million years ago -- by holding the rocks in both hands, to strike one against the other.
translation.zh: 记录片：Kanzi正在给自己做工具， 就像我们的祖先 250万年前一样－ 两手拿着石头互相敲击。