Modern life makes us tired, right? But research from societies in Africa and South America suggests people in the ancient world slept only 6.5 hours a night.

引言数月前，笔者曾写过一篇关于“巴黎奖牌”的科普文章，讲述铁矿石被用于修筑宏伟的巴黎铁塔，而铁塔的更换材料又被回收嵌于奖牌，见证人类的发展。文章引发了许多讨论，其中有一条评论引人深思：“埃菲尔铁塔的每一个零件都被更换过，那它还是原来的埃菲尔铁塔吗？” ...