If someone disturbs a bat cave so that thousands of them start to fly about, how is it that they do not bump into each other and get confused by each other's sound signals in the chaos?
當人們闖入蝙蝠洞穴，成千上萬的蝙蝠會不斷繞飛，但它們倒底以何種方法，在如一團拚命衝飛的火球當中，不致碰撞，訊號回收也不會互相干擾？