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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(More)
Birds in which both sexes produce complex song are more common in the tropics than in the temperate north, where typically only males sing. Yet surprisingly little is known about female song characteristics in most tropical species. Here we present a comparison of female and male singing behaviors in the Streak-backed Oriole (Icterus pustulatus), a tropical(More)
Female bird song and combined vocal duets of mated pairs are both frequently associated with tropical, monogamous, sedentary natural histories. Little is known, however, about what selects for duetting behavior versus female song. Female song likely preceded duet evolution and could drive apparent relationships between duets and these natural histories. We(More)
Both song and color patterns in birds are thought to evolve rapidly and exhibit high levels of homoplasy, yet few previous studies have compared the evolution of these traits systematically using the same taxa. Here we reconstruct the evolution of song in the New World orioles (Icterus) and compare patterns of vocal evolution to previously reconstructed(More)
Birds in which both sexes produce complex songs are thought to be more common in the tropics than in temperate areas, where typically only males sing. Yet the role of phylogeny in this apparent relationship between female song and latitude has never been examined. Here, we reconstruct evolutionary changes in female song and breeding latitude in the New(More)
Males of sexually dimorphic species often appear more divergent among taxa than do females, so it is often assumed that evolutionary changes have occurred primarily in males. Yet, sexual dimorphisms can result from historical changes in either or both of the sexes, and few previous studies have investigated such patterns using phylogenetic methods. Here, we(More)
Avian plumage colors are frequently used in studies of sexual selection, yet surprisingly little is known about how these traits evolve under different mating systems. We compared historical rates of divergence in male color patterns among the oropendolas and caciques (genera Cacicus, Gymnostinops, Ocyalus, and Psarocolius), a group with both polygynous and(More)
Carotenoid-based colors have signaling roles in a range of animal taxa, yet little is known about how carotenoids vary across species or whether overall patterns may vary across genera. The caciques (Cacicus, Clypicterus and Ocyalus; family Icteridae), a group of passerine birds from Central and South America, appear to visually divide into discrete yellow(More)
OBJECTIVE To assess the prognostic significance of presentation serum albumin, clinical stage and CA125 levels in ovarian cancer. DESIGN Retrospective analysis of data using a Cox proportional hazards model. SETTING A district general hospital oncology unit. SUBJECTS One hundred and fourteen consecutive patients with epithelial ovarian cancer. (More)