Mothers can influence the phenotype of their offspring by adjusting the quality of their eggs in relation to sex and reproductive value of the progeny. Maternal androgens in the eggs of vertebrates may mediate such adaptive early maternal effects. However, the evolution of early maternal effects...

Many animals have successfully adapted to human proximity, with dramatic increases in abundance as a consequence. Although such transitions imply a fitness advantage, the fitness benefits of associations between animals and humans have not been thoroughly investigated. In a comparative study of...

Adults of many species display extravagant sexual signals during the reproductive season, apparently evolved as a means of attracting mates or repelling potential competitors, thereby inadvertently also attracting the attention of predators. Many studies have shown predation costs of sexual...

Recent changes in temperature and precipitation have implications for transmission and excess attenuation of sounds, with important consequences for the choice of vocal display sites by animals. Birds typically sing from within or at the top of the vegetation, and the relative height of such...

Although heterospecific vocal imitation is well documented in passerines, the evolutionary correlates of this phenomenon are poorly known. Here, we studied interspecific variation in vocal mimicry in a comparative study of 241 European songbirds. We tested whether vocal mimicry is a mode of...