The effects of temperature and age on calling song in a field cricket with a complex calling song, Teleogryllus oceanicus (Orthoptera: Gryllidae) Sean E. Walker and William H. Cade Can. J. Zool./Rev. Can. Zool. 81(8): 1414-1420 (2003)
Abstract: We examined the effects of temperature and age on calling song in the field cricket Teleogryllus oceanicus. Teleogryllus oceanicus has a complex calling song made up of two different kinds of chirp, long and short. The long chirp is made up of three to eight single pulses of sound and the short chirp consists of several paired pulses. The properties of T. oceanicus calling song did not vary with age, but almost every property of the song varied with temperature. Pulse duration, interpulse interval, and pulse rate in both the long and the short chirp varied with temperature. The number of pulses in the long chirp, number of chirps in the short chirp, chirp rate in the short chirp, duration of the long chirp, carrier frequency of both the short and long chirps, and total song duration were also affected by temperature. The duration of the short chirp and the degree of frequency modulation were the only characteristics that did not vary with temperature. Temperature does not affect the properties of the long and short chirps in the same manner. The long chirp decreases in duration with temperature and has fewer pulses, while the short chirp stays the same in duration and contains a higher number of chirps. These data demonstrate that temperature influences calling-song parameters in a field cricket with a complex calling song. Endothermy and chorusing behaviour in the African platypleurine cicada Pycna semiclara (Germar, 1834) (Hemiptera: Cicadidae) Martin H. Villet, Allen F. Sanborn, and Polly K. Phillips Can. J. Zool./Rev. Can. Zool. 81(8): 1437-1444 (2003) Abstract: Cicadas use acoustic signals to find mates and therefore offer a phylogenetically independent opportunity to test the generality of ideas about acoustic communication that were developed from studies of other animals. Pycna semiclara (Germar, 1834) (Hemiptera: Cicadidae) is a forest-dwelling platypleurine cicada that uses its calling song to form choruses and attract mates. Additionally, P. semiclara produces an encounter call that is involved in courtship and also in spacing males within choruses. Males generally call from exposed trunks and branches within the understory but clear of the undergrowth and fight with other males that call within about 50 cm of them. Choruses sing sporadically throughout the day but focus most of their calling activity into half-hour bouts at dawn and dusk. Body size and ambient temperature had no significant effect on spectral or temporal characteristics of the calling song. Body temperature measurements indicate that P. semiclara thermoregulates endothermically, with a body temperature of more than 22 �C above ambient temperature being measured during calling activity at dusk. Such endothermy provides an advantage to the cicadas by allowing them to call during crepuscular hours when atmospheric conditions are most optimal for acoustic communication and predation risks are minimal. Coincidentally, endogenously regulating body temperature allows the temporal characteristics of the call to be unaffected by ambient temperature changes.
