Abstract Vocal behavior in tropical hummingbirds is a new area of study. Here, we present findings on the vocalizations and associated behaviors of two species: Sombre Hummingbird (Aphantochroa cirrhochloris) and Rufous-breasted Hermit (Glaucis hirsutus). These are the only hummingbirds in which the brain areas activated by singing have been demonstrated. They are also among the basal species of their respective subfamilies, Trochilinae and Phaethornithinae and, thus, represent early stages in the evolution of hummingbird vocal communication. We found that the two species exhibit distinctive vocalizations and behaviors. Sombre Hummingbird calls had more modulation and were often used during agonistic interactions, whereas Rufous-breasted Hermit calls had higher pitch and purer tones and were produced in less aggressive interactions. Sombre Hummingbird song was highly stereotyped in syllable structure and syntax, whereas Rufous-breasted Hermit song was highly variable. Comparative analysis points to consistent similarities in use of vocalizations by the Sombre Hummingbird and other trochilines, and by the Rufous-breasted Hermit and other phaethornithines. We hypothesize that differences in vocal behavior between hummingbird lineages arise as adaptations to their foraging strategies. Vocalizaciones y Comportamientos Asociados de Aphantochroa cirrhochloris y Glaucis hirsutus

中文翻译：

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黑蜂鸟 (APHANTOCHROA CIRRHOCHLORIS) 和红胸隐士 (GLAUCIS HIRSUTUS) 的发声和相关行为

摘要 热带蜂鸟的声音行为是一个新的研究领域。在这里，我们展示了两个物种的发声和相关行为的发现：暗色蜂鸟（Aphantochroa cirrhochloris）和红胸隐士（Glaucis hirsutus）。这些是唯一通过唱歌激活大脑区域的蜂鸟。它们也是各自亚科 Trochilinae 和 Phaethornithinae 的基础物种之一，因此代表了蜂鸟声音交流进化的早期阶段。我们发现这两个物种表现出独特的发声和行为。暗蜂鸟的叫声有更多的调制，经常在激动的互动中使用，而红胸隐士的叫声具有更高的音调和更纯的音调，并且在不那么积极的互动中产生。Sombre Hummingbird 的歌曲在音节结构和句法上是高度刻板的，而 Rufous-breasted Hermit 歌曲是高度可变的。比较分析表明，黑蜂鸟和其他 trochilines 以及红胸隐士和其他 phaethornithine 在使用发声方面存在一致的相似性。我们假设蜂鸟谱系之间发声行为的差异是由于对其觅食策略的适应而出现的。Vocalizaciones y Comportamientos Asociados de Aphantochroa cirrhochloris y Glaucis hirsutus 和红胸隐士和其他phaethornithines。我们假设蜂鸟谱系之间发声行为的差异是由于对其觅食策略的适应而出现的。Vocalizaciones y Comportamientos Asociados de Aphantochroa cirrhochloris y Glaucis hirsutus 和红胸隐士和其他phaethornithines。我们假设蜂鸟谱系之间发声行为的差异是由于对其觅食策略的适应而出现的。Vocalizaciones y Comportamientos Asociados de Aphantochroa cirrhochloris y Glaucis hirsutus