Avian plumage has captivated scientists and the public alike for generations and has been a
fundamental study system for research into signal evolution. By contrast, relatively little …

The control mechanisms and information content of melanin‐based colourations are still
debated among evolutionary biologists. Recent hypotheses contend that molecules involved …

Animal signals can differ considerably in complexity and composition, even among closely
related species. Work on vocal and visual signals has revealed how sexual selection can …

In species in which males signal competitive ability through secondary sexual traits, males
with different levels of trait expression may adopt different reproductive tactics to maximize …

The sexual ornamentation of animals typically consists of multiple distinct traits. The
classical research approach focuses on differences among these traits, but this approach …

Melanin is the most common pigment in animal integuments and is responsible for some of
the most striking ornaments. A central tenet of sexual selection theory states that melanin …

The malar stripes of falcons (Falco spp.) are often hypothesised to function by reducing the
amount of solar glare reflected into the falcon's eyes while hunting, thereby aiding foraging …

The outcome of social and sexual competition in animals is typically mediated through the
expression of body traits. Conspicuous characters such as yellow, orange, and red …

Most seabirds are monochromatic in plumage, yet many of them show multiple colored
integuments, typically modulated by sex steroids such as testosterone, which can reflect …

Numerous bird species exhibit striking white patches on their plumages that have been
reported as signals of individual quality in the context of sexual selection. Whereas …