Researchers have discovered a unique defense mechanism in leaf litter frogs, which they employ when faced with predators. These tiny amphibians emit ear-piercing ‘screams’ when attacked, aiming to repel their assailants. Remarkably, these screams are ultrasonic and cannot be heard by humans.
Leaf litter frogs, also known as Haddadus binotatus, are the most common frog species in South American forests. Despite their small size, with females reaching up to 64 millimeters in length, they utilize their high-frequency screams as a survival strategy.
While humans cannot hear these screams, potential predators such as bats, rodents, and small primates can detect them. The broad frequency range of the screams may serve to deter a variety of predators.
This discovery sheds light on the diverse communication methods employed by frogs in distress. Previous studies have noted frogs using vocalizations to signal distress, warnings, and alarms, but the ability to emit ultrasonic sounds is a new finding.
Using specialized software, researchers were able to detect the ultrasonic screams emitted by the leaf litter frogs, ranging from seven to 44 kilohertz. This capability opens up possibilities for further exploration of amphibian communication and behavior.
Given Brazil’s rich amphibian diversity, with over 2,000 species described, it is likely that other frogs also utilize high-frequency sounds for communication and defense. This study provides valuable insights into the fascinating world of frog communication and survival strategies.