Reconstructing the Evolution of Complex Bird Song in the Oropendolas

Abstract

The elaborate songs of songbirds are frequent models for investigating the evolution of animal signals. However, few previous studies have attempted to reconstruct historical changes in song evolution using a phylogenetic comparative approach. In particular, no comparative studies of bird song have used a large number of vocal characters and a well-supported, independently derived phylogeny. We identified 32 features in the complex vocal displays of male oropendolas (genera Psarocolius, Gymnostinops, and Ocyalus) that are relatively invariant within taxa and mapped these characters onto a robust molecular phylogeny of the group. Our analysis revealed that many aspects of oropendola song are surprisingly evolutionarily conservative and thus are potentially useful characters for reconstructing historical patterns. Of the characters that varied among taxa, nearly two thirds (19 of 29) showed no evidence of evolutionary convergence or reversal when mapped onto the tree, which was reflected in a high overall consistency index (CI = 0.78) and retention index (RI = 0.88). Some reconstructed patterns provided evidence of selection on these signals. For example, rapid divergence of the songs of the Montezuma oropendola, Gymnostinops montezuma, from those of closely related taxa suggests the recent influence of strong sexual selection. In general, our results provide insights into the mode of vocal evolution in songbirds and suggest that complex vocalizations can provide information about phylogeny. Based on this evidence, we use song characters to estimate the phylogenetic affinities of three oropendola taxa for which molecular data are not yet available.

Cultural evolution of killer whale calls: background, mechanisms and consequences

“…The occurrence of stable and variable features was also described in bird songs (Price & Lanyon, 2002). In European starlings (Sturnus vulgaris) whistle-like song types showed little variation, while other song types were extremely variable (Adret-Hausberger, 1989).…”

Novel vocal repertoire and paired swimbladders of the three-spined toadfish,Batrachomoeus trispinosus: insights into the diversity of the Batrachoididae

“…While acoustic call diversity and evolution are frequently discussed in tetrapods (e.g. Price and Lanyon, 2002;Ryan, 1986), similar evolutionary questions have not been extensively tested in fishes (but see Malavasi et al, 2008). Due to the relative simplicity of many central and peripheral vocal mechanisms (compared with tetrapods), fish typically lack the ability to produce complex and dynamic, frequency-modulated calls (Bass, 1997;Bass and McKibben, 2003;Demski et al, 1973;Rice and Lobel, 2003).…”

Phylogenetic comparative analysis of electric communication signals in ghost knifefishes (Gymnotiformes: Apteronotidae)

“…Evolutionary conservation of call structure in Atelopus frogs, for example, may result from the reduced importance of acoustic signals relative to visual signals in mate choice in this genus (Cocroft et al, 1990). Similarly, song components that are likely to be used in mate choice are evolutionarily labile in oropendolas, whereas other song components that are less likely to be mate assessment signals are conserved across species (Price and Lanyon, 2002).…”