When Neoconocephalus affinis males want to get a girl's attention,they don't turn up with flowers and chocolates: they chirrup. But it wasn't clear which aspect of their songs made a girl take note. Sarah Bush, Oliver Beckers and Johannes Schul from the University of Missouri decided to find out which components of the male's calls were essential and how the females tune in to the serenade (p. 648).

Recording males' serenades, the team placed a female N. affinis on a spherical treadmill in a darkened room, and measured the female's movements in response to the males' songs. Then they modified various aspects of the males' calls to see how the females reacted. Analysing the females' responses,the team realised that the females reacted most strongly to a 12.8 Hz component in the song's amplitude modulation by a neuronal membrane resonance mechanism. However, the 12.8 Hz component was not sufficient to get the females' attention. According to Bush, the overall shape of the chirrup was significant too.

Bush, S. L., Beckers, O. M. and Schul, J.(
). A complex mechanism of call recognition in the katydid Neoconocephalus affinis (Orthoptera: Tettigoniidae).
J. Exp. Biol.