The parabolas
Some animals have extremely good hearing and can hear a whisper from far away. You can also do this, if you use the right equipment!
Is it possible to whisper to each other 30 meters away outdoors? It is – if you use parabolas. A parabola has a structure that collects or spreads sound from its focus. When two parabolas are directed towards each other, it is possible to hear even weak sounds, if you put your ear at the focus of the parabola.