Iglesias Patricia P, Hasson Esteban
Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina.
Instituto de Ecología, Genética y Evolución de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Autónoma de Buenos Aires, Argentina.
PLoS One. 2017 May 3;12(5):e0176119. doi: 10.1371/journal.pone.0176119. eCollection 2017.
Courtship songs have undergone a spectacular diversification in the Drosophila buzzatii cluster. Accordingly, it has been suggested that sexual selection has played a significant role in promoting rapid diversification, reproductive isolation and speciation. However, there is no direct evidence (i.e., song playback experiments with wingless males) supporting this tenet. Moreover, several studies have showed that the courtship song in the genus Drosophila is not always used in female mate choice decisions, nor plays the same role when it is taken into account. In this vein, we use an approach that combines manipulative and playback experiments to explore the importance and the role of courtship song in female mate choice in four species of the D. buzzatii cluster and one species of the closely related D. martensis cluster for outgroup comparison. We also investigate the importance of courtship song in sexual isolation in sympatry between the only semi-cosmopolitan species, D. buzzatii, and the other species of the D. buzzatii cluster. Our study revealed that the courtship song is used by females of the D. buzzatii cluster as a criterion for male acceptance or influences the speed with which males are chosen. In contrast, we showed that this characteristic is not shared by D. venezolana, the representative species of the D. martensis cluster. We also found that the studied species of the D. buzzatii cluster differ in the role that conspecific and heterospecific songs have in female mate choice and in sexual isolation. Our findings support the hypothesis that divergence in female preferences for courtship songs has played a significant role in promoting rapid diversification and reproductive isolation in the D. buzzatii cluster. However, evidence from D. venezolana suggests that the use of the courtship song in female mate choice is not a conserved feature in the D. buzzatii complex.
求偶歌在拟果蝇类群中经历了显著的多样化。因此，有人提出性选择在促进快速多样化、生殖隔离和物种形成方面发挥了重要作用。然而，没有直接证据（即对无翅雄性进行歌声回放实验）支持这一观点。此外，多项研究表明，果蝇属的求偶歌并不总是在雌性配偶选择决策中被使用，即便被考虑在内，其作用也不尽相同。基于此，我们采用一种结合操纵实验和回放实验的方法，来探究求偶歌在拟果蝇类群的四个物种以及作为外群对照的近缘马氏果蝇类群的一个物种的雌性配偶选择中的重要性和作用。我们还研究了求偶歌在唯一的半世界性物种拟果蝇与拟果蝇类群的其他物种同域分布时的性隔离中的重要性。我们的研究表明，拟果蝇类群的雌性将求偶歌用作接受雄性的标准，或者影响选择雄性的速度。相比之下，我们发现马氏果蝇类群的代表物种委内瑞拉果蝇并不具备这一特征。我们还发现，拟果蝇类群中被研究的物种在同种和异种歌声在雌性配偶选择及性隔离中所起的作用方面存在差异。我们的研究结果支持了这样一种假说，即雌性对求偶歌偏好的差异在促进拟果蝇类群的快速多样化和生殖隔离方面发挥了重要作用。然而，来自委内瑞拉果蝇的证据表明，求偶歌在雌性配偶选择中的使用在拟果蝇复合体中并非一个保守特征。
