ABSTRACT Passerine song has many functions including mate attraction and territory defence. When songs across populations diverge, this can lead to changes in conspecific recognition and barriers to gene flow, which affect evolutionary processes that could lead to speciation. Two subspecies of thick-billed grasswren (Amytornis modestus) have a parapatric distribution characterised as a narrow region of high genetic admixture where the two subspecies meet. Outside the region of parapatry, the subspecies are genetically and morphologically diverged and weak inter-subspecific gene flow is asymmetric from A. m. indulkanna to A. m. raglessi. We examined the differences between song of A. m. indulkanna and A. m. raglessi and experimentally broadcast each subspecies song to compare territory-holder response in relation to intruder subspecies type. Our aim was to determine if territory owners have a different response to intruders based on the subspecific song type. The song of each subspecies contained unique vocal elements that were absent in the other subspecies. A. m. raglessi responded similarly to con-subspecific and hetero-subspecific intruder song, and A. m. indulkanna responded more often and with greater intensity to hetero- compared to con-subspecific intruder song. The stronger response by A. m. indulkanna towards hetero-subspecific intruders provides a plausible behavioural explanation for the observed patterns of asymmetrical gene flow.

中文翻译：

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厚嘴鹪鹩 (Amytornis normus) 的歌曲在亚种之间不同，并引起不同的亚种行为反应

摘要 Passerine 歌曲具有吸引配偶和领土防御等多种功能。当跨种群的歌曲出现分歧时，这可能导致同种识别的变化和基因流动的障碍，从而影响可能导致物种形成的进化过程。厚嘴鹪鹩 (Amytornis normus) 的两个亚种具有准地区分布，其特征是两个亚种相遇的高度遗传混合物的狭窄区域。在副区域外，亚种在遗传和形态上是不同的，亚种间的弱基因流与 A. m. 不对称。indulkanna 到 A. m. 拉格莱西 我们检查了 A. m. 之歌之间的差异。indulkanna 和 A. m. raglessi 并通过实验播放每个亚种的歌曲，以比较领土持有者对入侵者亚种类型的反应。我们的目标是根据特定的歌曲类型确定领土所有者是否对入侵者有不同的反应。每个亚种的歌曲都包含其他亚种所没有的独特的声乐元素。是。raglessi 对 con-subspecific 和hetero-subspecific intruder song 的反应类似，而 A. m. 与 con-subspecific 入侵者歌曲相比，indulkanna 对异种的反应更频繁，强度更大。A. m. 的反应更强。indulkanna 针对异种亚种入侵者的行为为观察到的不对称基因流模式提供了合理的行为解释。raglessi 对 con-subspecific 和hetero-subspecific intruder song 的反应类似，而 A. m. 与 con-subspecific 入侵者歌曲相比，indulkanna 对异种的反应更频繁，强度更大。A. m. 的反应更强。indulkanna 针对异种亚种入侵者的行为为观察到的不对称基因流模式提供了合理的行为解释。raglessi 对 con-subspecific 和hetero-subspecific intruder song 的反应类似，而 A. m. 与 con-subspecific 入侵者歌曲相比，indulkanna 对异种的反应更频繁，强度更大。A. m. 的反应更强。indulkanna 针对异种亚种入侵者的行为为观察到的不对称基因流模式提供了合理的行为解释。