Birds exhibit remarkable variation in plumage patterns, both within individual feathers and
among plumage patches. Differences in the size, shape, and location of pigments and …

To what extent do individuals assess the cognitive abilities of the opposite sex when
choosing a mate? With the exception of song learning in birds, the hypothesis that cognitive …

Parrot feathers contain red, orange, and yellow polyene pigments called psittacofulvins.
Budgerigars are parrots that have been extensively bred for plumage traits during the last …

Understanding how animals achieve simultaneous conspicuousness to intended receivers
and crypsis to unintended receivers requires investigating the distribution, size, and spectral …

This is the first book to summarize the methods, conceptual issues and results of studies
using the interpretation of feather growth rates as an index of nutritional condition in birds …

Parrots produce stunning plumage colors through unique pigments called psittacofulvins.
However, the mechanism underlying their ability to generate a spectrum of vibrant yellows …

Parrots of the Wild explores recent scientific discoveries and what they reveal about the lives
of wild parrots, which are among the most intelligent and rarest of birds. Catherine A. Toft …

Models of sexual selection by mate choice have emphasized the evolution of sexually
dimorphic costly signals, such as elaborate plumage or courtship display, in the sex …

In many birds, red, orange and yellow feathers are coloured by carotenoid pigments, but
parrots are an exception. For over a century, biochemists have known that parrots use an …

The evolution and signalling content of female ornamentation has remained an enduring
challenge to evolutionary biologists, despite the fact that secondary sexual characters are …