Danionella cerebrum, a translucent fish species of only 12 mm length, produces high amplitude sounds exceeding 140 dB (re. 1 µPa, at a distance of one body length) — comparable to a jet engine during take-off in 100 m distance. Danionella cerebrum has a pair of extrinsic, indirect sonic muscles that house the drumming cartilage. When a sonic muscle contracts, the fifth rib is pulled anteriorly and builds tension as it pulls the cartilage. The...
