Modern life makes us tired, right? But research from societies in Africa and South America suggests people in the ancient ...

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.

大年初三，有安睡迟起的习俗，这和春节期间前几日的忙碌形成鲜明对比。春节假期步入第三天，大家都在新年的喜庆氛围里尽情放松。前几天，人们忙着筹备年货、贴春联、准备年夜饭，走亲访友也耗费不少精力，到了初三，就可以好好睡个懒觉。