translation.en: Hand axes mark an evolutionary advance in human history -- tools fashioned to function as what Darwinians call "fitness signals" -- that is to say, displays like the peacock's tail, except that, unlike hair and feathers, the hand axes are consciously cleverly crafted.
translation.zh: 手斧标志了 人类历史上进化的进步-- 从实用工具到审美对象 就好像达尔文主义者所说的适应性信号 这就是说，它展示出了 类似孔雀尾巴 的用途， 只是与毛发和羽毛不同， 手斧是有意识的 精巧制品。