02020nas a2200229   4500008004100000022001400041245007800055210006900133260001600202300001400218490000700232520133100239653002701570653001401597653001401611653002601625653002601651653002101677100001801698700001901716856005501735       2006                        eng d  a0028-104200aWhen males whistle at females: complex FM acoustic signals in cockroaches0 aWhen males whistle at females complex FM acoustic signals in coc  cJan-10-2006  a500 - 5050 v933 a<p>Male cockroaches of the species Elliptorhina chopardi expel air through a pair of modified abdominal spiracles during courtship. This air expulsion simultaneously produces air and substrate-borne vibrations. We described and compared in details these two types of vibrations. Our analysis of the air-borne signals shows that males can produce three categories of signals with distinct temporal and frequency parameters. &ldquo;Pure whistles&rdquo; consist of two independent harmonic series fast frequency modulated with independent harmonics that can cross each other. &ldquo;Noisy whistles&rdquo; also possess two independent voices but include a noisy broad-band frequency part in the middle. Hiss sounds are more noise-like, being made of a broad-band frequency spectrum. All three call types are unusually high in dominant frequency (&gt;5 kHz) for cockroaches. The substrate-borne signals are categorised similarly. Some harmonics of the substrate-borne signals were filtered out, however, making the acoustic energy centered on fewer frequency bands. Our analysis shows that cockroach signals are complex, with fast frequency modulations and two distinct voices. These results also readdress the question of what system could potentially receive and decode the information contained within such complex sounds.</p>
10aacoustic communication10aCockroach10acourtship10aElliptorhina chopardi10afrequency modulations10atwo-voice system1 aSueur, Jerome1 aAubin, Thierry  uhttp://link.springer.com/10.1007/s00114-006-0135-9