Johnsen A, Lifjeld JT, Rohde PA
Zoological Museum, University of Oslo
Anim Behav. 1997 Jul;54(1):121-30. doi: 10.1006/anbe.1996.0437.
Artificial traits such as coloured leg bands may affect an individual's mating success, as shown for some birds. One explanation is that colour-matching with a sexual ornament affects the individual's sexual attractiveness. This study reports a colour-band experiment with free-living bluethroats, Luscinia s. svecicaa species where males have a distinct blue and chestnut throat and upper breast. There was no apparent difference in pairing success between males with ornament-matching colour bands (blue and orange) and males with non-ornamental colour bands. However, males with ornamental bands guarded their mates less intensely and spent more time singing, performing song flights and intruding into neighbours' territories than males with non-ornamental bands. We conclude that colour bands affect the trade-off between mate guarding and advertisement behaviour in a way that is consistent with the hypothesis that bands with ornamental colours improve a male's attractiveness. The results are in concordance with a previous study of the same population, showing that males with experimentally reduced attractiveness guarded their mates more closely and advertised less for additional mates, than non-manipulated males.
诸如彩色脚环之类的人工特征可能会影响个体的交配成功率，一些鸟类的情况就是如此。一种解释是，与性装饰的颜色匹配会影响个体的性吸引力。本研究报告了一项针对自由生活的蓝喉歌鸲（Luscinia s. svecica）的色环实验，该物种的雄性具有独特的蓝色和栗色喉咙及上胸部。佩戴与装饰匹配色环（蓝色和橙色）的雄性与佩戴非装饰性色环的雄性在配对成功率上没有明显差异。然而，佩戴装饰性色环的雄性比佩戴非装饰性色环的雄性对配偶的守护力度更小，花更多时间唱歌、进行歌飞以及侵入邻居领地。我们得出结论，色环以一种与装饰性颜色的色环能提高雄性吸引力这一假设相一致的方式，影响了配偶守护和求偶行为之间的权衡。这些结果与之前对同一群体的研究结果一致，表明实验性降低吸引力的雄性比未处理的雄性更紧密地守护配偶，对额外配偶的求偶行为更少。
