The world's loudest animal relative to its size has been revealed to be a tiny bug with a big organ. Specifically, the water boatman, Micronecta scholtzi, rattles its penis along grooves in its abdomen to produce a chattering song—that registers at 99.2 decibels—about the volume of a loud orchestra heard from the front row. Scientists presenting at the Society for Experimental Biology annual conference in Glasgow recorded the bug and analyzed its volume compared to various other loud animals. Even though the water boatman does its "singing" from the bottom of rivers to attract mates, humans walking along the riverbank can clearly hear it. The area along its abdomen that the bug uses to make the noise is only about the width of a human hair, and researchers aren't sure exactly how it produces so loud a song.
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