Measures of body condition, immune function, and hematological health are widely used in
ecological studies of vertebrate populations, predicated on the assumption that these traits …

Despite classical expectations of a trade-off between immune activity and reproduction, an
emergent view suggests that individuals experiencing activation of their immune system …

It is generally assumed that larger juveniles are more physiologically mature, hence their
overall condition and subsequent performance are higher. Some taxa face extreme …

A major component of sex‐allocation theory, the Trivers–Willard model (TWM), posits that
sons and daughters are differentially affected by variation in the rearing environment. In …

The honesty of structural-based ornaments is controversial. Sexual selection theory predicts
that the honesty of a sexual signal relies on its cost of production or maintenance. Therefore …

Infectious disease threatens biodiversity and human health on a global scale, and disease
emergence may become more common as humans further encroach on habitats and modify …

Immune defenses vary widely across individuals and species. The field of evolutionary and
ecological immunology (also recognized as ecoimmunology) seeks to uncover both the …

Despite keen interest in extra-pair mating in birds, its adaptive significance remains
unresolved. Here, we use a multi-year dataset to test whether traits of a female's social mate …

Variation in parental age can have important consequences for offspring fitness and the
structure of populations and disease transmission. However, our understanding of the …

Reproductive success often declines with breeding date in diverse taxa, including temperate-
nesting bird species. The date hypothesis predicts that seasonally deteriorating …