Department of Evolutionary Biology, Bielefeld University Morgenbreede 45, 33615, Bielefeld, Germany.
Ecol Evol. 2012 Aug;2(8):1914-21. doi: 10.1002/ece3.309. Epub 2012 Jul 11.
In many animal species, male acoustic signals serve to attract a mate and therefore often play a major role for male mating success. Male body condition is likely to be correlated with male acoustic signal traits, which signal male quality and provide choosy females indirect benefits. Environmental factors such as food quantity or quality can influence male body condition and therefore possibly lead to condition-dependent changes in the attractiveness of acoustic signals. Here, we test whether stressing food plants influences acoustic signal traits of males via condition-dependent expression of these traits. We examined four male song characteristics, which are vital for mate choice in females of the grasshopper Chorthippus biguttulus. Only one of the examined acoustic traits, loudness, was significantly altered by changing body condition because of drought- and moisture-related stress of food plants. No condition dependence could be observed for syllable to pause ratio, gap duration within syllables, and onset accentuation. We suggest that food plant stress and therefore food plant quality led to shifts in loudness of male grasshopper songs via body condition changes. The other three examined acoustic traits of males do not reflect male body condition induced by food plant quality.
在许多动物物种中，雄性的声音信号用于吸引配偶，因此通常对雄性的交配成功起着重要作用。雄性的身体状况可能与雄性的声音信号特征有关，这些特征可以反映雄性的质量，并为有选择的雌性提供间接的好处。环境因素，如食物的数量或质量，会影响雄性的身体状况，并可能导致声音信号吸引力的条件依赖性变化。在这里，我们通过这些特征的条件依赖性表达来测试食物植物的压力是否会影响雄性的声音信号特征。我们研究了四种对雌性蝗虫 Chorthippus biguttulus 的择偶至关重要的雄性歌曲特征。只有一个被检查的声学特征，即响度，由于食物植物的干旱和水分相关压力而改变了身体状况，这一特征发生了显著变化。在音节到停顿的比例、音节内的间隙持续时间和起始强调方面，没有观察到条件依赖性。我们认为，食物植物的压力，以及因此食物植物的质量，通过身体状况的变化，导致雄性蝗虫歌声的响度发生变化。雄性的另外三个被检查的声学特征不能反映食物植物质量引起的雄性身体状况。
