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Abstract. Male calling and searching tactics are described for a duetting Australian bushcricket, Caedicia sp. 12 (Phaneropterinae; Tettigoniidae; Orthoptera). The repertoire of Caedicia sp. 12 consists of the calling song and, by nonduetting males, a series of calling tactics that include short-click calling, disruptive over-singing and a call mimicking the entire duet. Nonduetting males respond to the production of a duet by another male and a female with short-click calls that mimic the female call at the conclusion of a duet. By manipulating the male's mating history, it is found that this form of calling behaviour is more likely to occur within the male's 6-day postmating refractory period; the low cost tactic allows males to re-mate during spermatophore replenishment. Males also produce disruptive calls in response to a duet, where the male may over-sing the duetting male's signal or produce a call that appears to mimic the entire duet; the male produces a calling song followed by a short signal that has the same latency as the female's reply within a duet. Males also over-sing crucial elements of the duetting-male's song that are normally critical for the female's conspecific recognition. There is no evidence that females search for the duetting male partner, but males unable to enter a duet will search for the call of a responding female. Searching by males is more common when these males are producing disruptive calls. Alternative male calling tactics are discussed as a set of conditional strategies for securing unmated females. 相似文献
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The Relationship between Sucrose and Starch during 'Dark' Export from Leaves of Uniculm Barley 总被引:7,自引:0,他引:7
Uniculm barley plants were grown in 8 h photoperiods at a quantumflux density of 655 µE m2 s1. Groups ofplants were transferred to four different light environmentsfor one 8 h photoperiod (106, 270, 665, and 975 µE m2s1) and harvested at intervals throughout the succeedingdark period for subsequent carbohydrate analysis of the youngestmature leaf. Sucrose was the predominant carbohydrate in the leaves (attaininga level of c. 100 mg dm2 after 8 h at 975 µE m2s1) but starch was also of significance (20 mg dm2after 8 h at 975 µE m2 s1). During the dark period, following a photoperiod at the threehighest light levels (270, 665, and 975 µE m2 s1),sucrose was exported first while the starch level remained fairlyconstant. When the-sucrose level fell to 1520 mg dm2starch degradation began. This critical sucrose level was reachedearlier in those plants subjected to lower quantum flux densitiesduring the preceding photoperiod. The delay in the remobilizationof starch suggests an important regulatory mechanism which maybe dependent upon the sucrose level. At 106 µE m2s1 the sucrose level rose to only 10 mg dm2. Herethere was no discernible delay in the depletion of sucrose orstarch. 相似文献
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