Acoustic communication has played a key role in the evolution of animals especially vertebrates and insects. Recently, an international team led by NIGPAS carried out a detailed and global investigation of fossil katydids from the Mesozoic Era. The study provides novel insights on acoustic evolution of Mesozoic katydids and evolution of the Mesozoic soundscape. It was published in PNAS on December 12, 2022.
The research team reported the earliest tympanal ears and sound-producing system (stridulatory apparatus) in exceptionally preserved Mesozoic katydids. It demonstrated that katydids had evolved complex acoustic communication, including mating signals, inter-male communication, and directional hearing, at least by the Middle Jurassic.
Also, the Early and Middle Jurassic katydid transition from extinct haglid- to extant prophalangopsid-dominated insect faunas coincided with the diversification of derived mammalian groups (clades) and improvement of hearing in early mammals, supporting the hypothesis of acoustic co-evolution of mammals and katydids.
These results also highlight the ecological significance of insects in the Mesozoic soundscape, which has hitherto been largely unknown in the palaeontological record.