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.

Day 1Marcel是我们这一次清迈之旅最大的收获。在预定酒店的时候，误打误撞地，在booking上找到他的这家Golden Teak Home ...

Scientists researching Alpine glaciers store ice in Antarctica. By analysing air bubbles in the ice they may be able to predict the future ...