Females may choose mates based on the expression of secondary sexual characters that
signal direct, material fitness benefits or indirect, genetic fitness benefits. Genetic benefits …

Vitamin A is essential for life in all vertebrate animals. Vitamin A requirement can be met
from dietary preformed vitamin A or provitamin A carotenoids, the most important of which is …

Malarial parasites are supposed to have strong negative fitness consequences for their
hosts, but relatively little evidence supports this claim due to the difficulty of experimentally …

Carotenoids are a large group of more than 500 different biochemicals synthesized by
bacteria, fungi, algae and plants. Higher animals obtain these biologically active pigments in …

Carotenoid pigments are used by many bird species as feather colorants, creating brilliant
yellow, orange, and red plumage displays. Such carotenoid‐based plumage coloration has …

Mechanisms maintaining honesty of sexual signals are far from resolved, limiting our
understanding of sexual selection and potential important parts of physiology. Carotenoid …

Carotenoid-based sexual coloration has been hypothesised to be prevalent across many
vertebrate taxa because it reliably reflects individual phenotypic quality in terms of foraging …

Variation in the prevalence of blood parasites among species of birds has been used to test
hypotheses about the effects of sexual selection and parental investment on disease …

1. Great Tits (Parus major) derive the carotenoid pigments for their yellow plumage via the
prey items in their diet. Air pollution is known to affect the abundance of many forest insects …

Reproduction and maintenance compete for resources within a single individual. But do
individuals invest in reproduction just as much as remains after the requirements of …