But since infrasound in the air is known to travel much further then a mile and a half (two kilometers), it's hard to be sure if elephants ever notice the seismic side of their calls or use them as a back up lineon noisy days.
But since infrasound in the air is known to travel much further then a mile and a half (two kilometers), it's hard to be sure if elephants ever notice the seismic side of their calls or use them as a back up lineon noisy days.
但因为次声在空气中传播的距离要远大于两公里，所以很难断定大象是否留意到了地震波的信息，还是只是在地表嘈杂的日子把它作为一条备份“专线”。