Deep in the rainforest in a northern corner of the Republic of Congo, some of the most sophisticated monitoring of animal sounds on earth is taking place. Acoustic sensors are collecting large amounts ...

Deep in the rainforest in a northern corner of the Republic of Congo, some of the most sophisticated monitoring of animal sounds on earth is taking place. Acoustic sensors are collecting large amounts ...

In the vast African savanna, an elephant lifts its head, pauses for a moment and begins to walk. No call, no trumpet, not even any visible signal. Miles away, another herd does the same. No sound ...