| Summary: | 碩士 === 國立臺灣師範大學 === 生命科學系 === 106 === Contact zones between sibling species are nature laboratories for evolutionary and ecological studies. In the genetic view, contact zones provide a good place to exam the genetic integrity of species. In the ecological view, the competition, communication and interaction between species were well studied in acoustic-communicated species such as frogs, birds, and some insects. The signal discrimination between two species is crucial to communication and species recognition, which may affect species fitness directly (female choice) or indirectly (male discrimination). Buergeria japonica and B. otai are sister species which use similar niche and communication signals. In Taiwan, they distribute in different drainages, forming two narrow contact zones in eastern (Yilan) and western (Jiayi) Taiwan. The acoustic signals they use include sharing long call (Type 1a of B. japonica and Type 1b of B. otai) and a unique long call (Type 2) of B. otai. In this study, I aim to test whether the divergence of acoustic signal plays a role on the barrier of gene flow. I conducted playback experiment to males both species to exam their response toward conspecific and heterospecific signals. The result shows symmetric result that both species response more to conspecific long call, implying their correct species recognition. In the test of gene flow, I obtained genome-wide SNPs by using RAD-seq. The assignment test showed no recent gene flow between two species, although ancient introgressions from B. japonica to B. otai in both contact zones were detected. The consistent results between genetic and behavioral experiments suggest that the discrimination of acoustic signal functions as a barrier of recent gene flow.
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