Competition over mates takes many forms and has far-reaching consequences for many
organisms. Recent work suggests that relative reproductive rates of males and females …

Bird song is generally associated with males. In part, this reflects a bias towards studies in
temperate regions, because in the tropics females of many species are regular and prolific …

Traits correlated with male mating success are likely to be subject to sexual selection.
Sexually selected characters are thought to be costly to develop and maintain. If males do …

Is the cost of reproduction different between males and females? On the one hand, males
typically compete intensely for mates, thus sexual selection theory predicts higher cost of …

When Darwin first proposed the possibility of sexual selection, he identified two
mechanisms, male competition for mates and female choice of mates. Extending this …

To study the relative importance of factors with direct and indirect effects on male fitness in
the polygynous Great Reed Warbler, Acrocephalus arundinaceus, I investigated …

We investigated the signaling function of blue plumage in male blue grosbeaks (Guiraca
caerulea) to determine if structurally based coloration may act as a reliable signal of quality …

Immunosuppressive effects of testosterone lead to a prediction of male-biased parasitism.
To test this prediction, prevalences of blood parasites were compared between male and …

Recent sexual selection studies on the evolution of bird colouration have mainly focused on
signals with a high level of condition-dependent variation, with much less attention given to …

This study tested whether female red-winged blackbirds, Agelaius phoeniceusacquire non-
genetic, material benefits from copulating with multiple males. In this population, females …