Loudest penis

The loudest penis is that of a tiny European species of aquatic freshwater insect. Micronecta scholtzi is a very small water boatman, just 2 mm long, but when it rubs its penis against its abdomen (a process known as stridulation, which serves to attract a mate), the chirping noise created can be up to 99.2 decibels. This is equivalent to sitting in the front row listening to a loud orchestra playing. The research was published in the journal PLOS ONE on 15 June 2011.

While there is a body of research into the vocalizations of marine and terrestrial mammals, this study set to shine the spotlight on the lesser-known sounds produced by small arthropods.

While the peak sound produced by Micronecta scholtzi falls considerably below that of much larger animals such as whales, dolphins, elephants and bison, taking scale into consideration the authors suggest it has the highest ratio dB/body size of any animal: 31.5, vs an average of 6.9 for most larger animals. The next highest ratio dB/body size is 19.63 for the snapping shrimp Synalpheus parneomeris.

The research was conducted by the Museum national d’Histoire naturelle (France) and the Centre for Ultrasonic Engineering at the University of Strathclyde (UK), led by bioacoustics specialist Dr Jérôme Sueur.