Huffington Post: A curtain of sound envelops the two researchers as they make their way along the side of a mountain in darkness, occasionally hacking their way with a machete to reach the mouth of a small cave.
Peeps, tweets and staccato whistles fill the air, a pulsing undercurrent in the tropical night. To the untrained ear, it's just a mishmash of noise. To experts tracking a decline in amphibians with growing alarm, it's like a symphony in which some of the players haven't been showing up.
In parts of...