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

Carotenoids are of great interest due to their essential biological functions in both plants and
animals. However, the properties and functions of carotenoids in natural systems are …

We evaluated the oxidative cost paid by birds when coping with an immune challenge. We
used the phytohaemagglutinin skin test (PHA) to assess the effects of the T-cell-mediated …

The fitness of an organism can be affected by conditions experienced during early
development. In light of the impact that oxidative stress can have on the health and ageing of …

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 …

Carotenoid pigments cannot be synthesized by vertebrates but must be ingested through the
diet. As they seem to be a limited resource, carotenoid-based ornaments are particularly …

Birds control body homeostasis through the secretion of corticosterone. This hormone is the
end-product of the hypothalamic–pituitary–adrenal (HPA) axis response to stressors. High …

Carotenoids are considered a limited resource for animals because they are not synthesised
by the body. Birds use carotenoids, mainly xanthophylls, for physiological functions, such as …

The genetic covariation among different traits may cause the appearance of correlated
response to selection on multivariate phenotypes. Genes responsible for the expression of …

As the world experiences rapid urban expansion, natural landscapes are being transformed
into cities at an alarming rate. Consequently, urbanization is identified as one of the biggest …