SUMMARY (i) To find out whether a mating preference could have initially evolved for
adaptive reasons, one must determine whether the preferred trait could have provided …

Although physically homogeneous, birds come in a wide variety of colors, rivaling butterflies
and tropical reef fishes. Such variation invites attention and many hypotheses have been …

Recent evidence suggests that sexually selected traits have unexpectedly high genetic
variance. In this paper, we offer a simple and general mechanism to explain this …

One hundred years after Darwin considered how sexual selection shapes the behavioral
and morphological characteristics of males for acquiring mates, Parker realized that sexual …

The aerodynamic properties of a bird's tail, and the forces produced by it, can be predicted
by using slender lifting surface theory. The results of the model show that unlike …

Sexual displays often involve several different ornamental traits. Yet most indicator models
of sexual selection based on a single receiver (usually a choosy female) find that multiple …

Independent of age or geographic variation, males of many species of birds exhibit dramatic
variation in the expression of elaborate secondary sexual characters." Good genes" models …

1. Relationships between foraging strategy, flight performance and wing shape in animals
can be demonstrated with the use of aerodynamic theory. The optimal morphology is …

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 …

NEURONS sensitive to both place and direction from distinct regions of the hippocampal
formation1–2, allometric relationships between spatial learning and hippocampal structure3 …