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 …

Abstract The Evolution of Avian Breeding Systems deals with three of the most conspicuous
and fascinating aspects of the reproductive biology of birds: sexual selection, parental care …

Polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and
polychlori nated dibenzofurans (PCDFs) are structurally related families of persistent organic …

Both in the past and up to the present, birds have figured prominently as models in several
areas of evolutionary biology, such as those of speciation (eg, Mayr, 1963) and sexual …

Life-history theory predicts that individuals should adjust their reproductive effort according
to the expected fitness returns on investment. Because sexually selected male traits should …

Males play a variable parental role in reproduction, ranging from no male parental care to
extensive male care. Females may acquire either direct or indirect fitness benefits from their …

Species with paternal care show less exaggerated sexual ornamentation than those in
which males do not care, although direct benefits from paternal care can vastly exceed the …

Harriers are a charismatic group of birds of prey with a worldwide distribution that have long
fascinated bird watchers and scientists. Here for the first time the biology of the world's …

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 …

Good parent and differential allocation models predict relationships between degree of
sexual ornamentation and parental care, but relatively few studies have tested these …