Data from: Song evolution, speciation, and vocal learning in passerine birds

Phenotypic divergence can promote reproductive isolation and speciation, suggesting a possible link between rates of phenotypic evolution and the tempo of speciation at multiple evolutionary scales. To date, most macroevolutionary studies of diversification have focused on morphological traits, whereas behavioral traitsincluding vocal signalsare rarely considered. Thus, although behavioral traits often mediate mate choice and gene flow, we have a limited understanding of how behavioral evolution contributes to diversification. Furthermore, the developmental mode by which behavioral traits are acquired may affect the rates of behavioral evolution, although this hypothesis is seldom tested in a phylogenetic framework. Here, we examine evidence for rate shifts in vocal evolution and speciation across two major radiations of codistributed passerines: one oscine clade with learned songs (Thraupidae) and one suboscine clade with innate songs (Furnariidae). We find that evolutionary bursts in rates of speciation and song evolution are coincident in both thraupids and furnariids. Further, overall rates of vocal evolution are higher among taxa with learned rather than innate songs. Taken together, these findings suggest an association between macroevolutionary bursts in speciation and vocal evolution, and that the tempo of behavioral evolution can be influenced by variation in developmental modes among lineages.

表型分化可推动生殖隔离与物种形成，这提示在多个演化尺度上，表型演化速率与物种形成速率之间存在潜在关联。迄今为止，绝大多数针对物种多样化的宏观演化研究均聚焦于形态性状，而行为性状（包括发声信号）却极少被纳入考量。因此，尽管行为性状通常会介导配偶选择与基因流，但我们对行为演化如何推动物种多样化的认知仍十分有限。此外，行为性状的获得发育模式或许会影响行为演化速率，不过这一假说极少在系统发育框架下得到验证。本研究针对两类同域分布的雀形目主要辐射类群，检验了发声演化与物种形成的速率转变相关证据：一类为具备习得鸣唱的鸣禽演化支——裸鼻雀科（Thraupidae），另一类为具备先天鸣唱的亚鸣禽演化支——灶鸟科（Furnariidae）。研究发现，裸鼻雀类与灶鸟类中，物种形成与鸣唱演化的速率演化爆发均呈现重合态势。此外，拥有习得鸣唱的类群，其整体发声演化速率高于具备先天鸣唱的类群。综合上述结果，本研究的发现表明：物种形成与发声演化的宏观演化爆发之间存在关联，且行为演化的速率可受不同世系间发育模式差异的影响。