Song evolution and speciation in East-African bush-crickets (Orthoptera, Tettigonioidea)

物种形成的过程通常只使用形态学或遗传数据来研究，而没有关于动物行为的确切信息。然而，在声音交流的动物中，交配行为的重要部分可以被记录和分析。这为测量和比较形态和行为特征的进化速度以及估计它们对物种形成的重要性提供了独特的可能性。我们将集中研究东非灌木蟋蟀的两个属（昆虫科：蟋蟀科：Phlesirtes， Aerotegmina），目前正在对它们的系统发育关系和年龄进行调查（Wägele Wa 530/30）。由于在直翅目昆虫中，鸣声模式是生殖隔离的重要组成部分之一，因此我们希望对声通信系统的进化过程有一个全面的了解。结果将证明行为是否可以被视为物种形成的步调制定者，以及在这种情况下，种内（例如，性选择）或种间过程是否更重要。种群或物种的分离从冰河时代一直延续到几百万年前。这两个属在生态学（Phlesirtes， conocephaline灌木蟋蟀居住在草原上；Aerotegmina， listroscelidine灌木蟋蟀居住在树冠上）、鸣叫模式和传播历史上都有所不同。

The process of speciation is often studied using morphological or genetic data only without exact information about the behaviour of the animals. In acoustically communicating animals, however, important parts of mating behaviour can be registered and analysed. This offers a unique possibility to measure and compare the speed of evolution in morphological as well as behavioural traits and estimate their importance for speciation. We will concentrate on two genera of East African bush-crickets (Insecta: Tettigioniidae: Phlesirtes, Aerotegmina) for which phylogenetic relationships and age of the species involved are currently under investigation (Wägele Wa 530/30). Since in Orthoptera the calling song pattern is one of the most important components of reproductive isolation, we expect to get a picture of evolution in progress of acoustic communication systems. The results will demonstrate if behaviour can be regarded as pace maker for speciation and if in this case intra- (e.g., sexual selection) or interspecific processes are more important. The isolation of the populations or species respectively extends from ice ages up to several million years ago. Both genera differ in ecology (Phlesirtes, conocephaline bush-crickets inhabiting grasslands; Aerotegmina, listroscelidine bush-crickets inhabiting the canopy), in song pattern and also in the history of dispersal.