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.
人口结构、城市化、政治和消费科技的变化,使得非洲大陆正在经历深刻的社会变革。但这种变革并未得到经济转型的支撑。相反,非洲经济正逐渐落后于世界其他地区。1960年,非洲基于购买力平价(PPP)的人均GDP约为世界其他地区平均水平的一半。而如今,这一比例 ...