“…These elements often include rapid frequency modulations (Adret-Hausberger & Jenkins, 1988;Eens et al, 1989Eens et al, , 1992aHausberger, 1997). Click and high frequency motifs are generally found in all wild-caught adult male birds (Adret- Hausberger & Jenkins, 1988;Eens, Pinxten, & Verheyen, 1991a) whereas they can lack or can be far less produced by females (Hausberger & Black, 1991;Hausberger, Richard-Yris, Henry, Lepage, & Schmidt, 1995;Pavlova, Pinxten, & Eens, 2005). The production of click and high frequency motifs is accompanied by different patterns of wing movements specific to male birds (wing-flicking for click motifs and more frequently wing-waving for high frequency motifs (Böhner & Veit, 1993;Eens et al, 1989)).…”