Bare-Throated Bellbird and Red-Legged Seriema Identified as World's Loudest Birds

Gist Researchers have identified the bare-throated bellbird and the red-legged seriema as the loudest known birds, recording their calls at staggering volumes between 121 and 122 decibels . Published in the journal Evolution , this study represents the largest cross-species comparison of sound amplitude in avians, mapping the acoustic profiles of 123 species . For UPSC aspirants, this highlights a significant development in bioacoustics, mapping fundamental physics amplitude to evolutionary biology and spotlighting specific neotropical habitats. Background Amplitude is a physical measure of a sound wave's height, which dictates both how loud a sound is perceived to be and the distance it can travel through a given environment. Historically, precise measurement of birdsong amplitude in the wild was considered a "black box" in ornithology, leaving a data gap even for common species like the Canada goose. The primary challenge was methodological: accurately measuring amplitude requires isolating a specific animal's call from dense background noise while simultaneously calculating the exact distance between the recording microphone and the subject. Key Pointers The study bridges a critical gap in field biology by combining…