Scientists in Argentina have recorded what they say are high-pitched screams by tadpoles in distress. It's the first time any kind of underwater larvae have been identified as capable of making a sound. The discovery may have significant implications for future amphibian research.<br /><br />At the University of La Plata, Argentina, researchers have discovered that tadpoles of the species commonly known as Pacman frogs, emit high-pitch screams while underwater. <br /><br />Video recordings by the scientists show that the tadpoles let off a sharp, metallic sound when they run into other tadpoles, or feel they are under attack. <br /><br />Frogs are well known for croaking in mating rituals, but globally, tadpoles have never been known to make sounds.<br /><br />Researcher at CONICET and investigator at the University’s Environmental Studies Center, is Guillermo Natale. <br /><br />[Guillermo Natale, Lead Scientist]: (Male, Spanish)<br />"Everyone has heard the sounds [frogs make] in the atmosphere, but nobody thought to put a microphone underwater to see what the tadpoles did.”<br /><br />Pacman frogs, which are popular household pets in many countries, are also ferocious carnivores. <br /><br />The frogs eat birds, insects, small mammals and other frogs almost as big as themselves. <br /><br />[...] <br /><br />Research assistant, Raul Herrera says they believe the screams from the tadpoles are defensive sounds used to tell their siblings that they are members of the same species. <br /><br />[Raul Herrera, Research Assistant]: (Male, Spanish)<br />"When the tadpoles are in the same tank as other tadpoles they hunt the tadpoles of other species, but not tadpoles that are of the same species.”<br /><br />The Argentine scientists carried out the study after noticing the tadpoles screamed when taken out of the water. <br /><br />Next, the scientists want to analyze other similar species to see if they too shriek when under threat.
