A study reported in the journal acta ethologica has recorded the use of ultrasound by amphibians for the first time in South America. It also describes the first documented case of the use of ultrasound for defense against predators, in a distress call of ear-piercing intensity to many animals, but inaudible to humans. ... read full story
"In light of the fact that amphibian diversity in Brazil is the highest in the world, with more than 2,000 species described, it wouldn't be surprising to find that other frogs also emit sounds at these frequencies,"