Evolution of life history traits can be studied at two different levels:(1) current selection
processes, including trade-offs in life history traits in natural populations as revealed by …

There are many different types of organisms in the world: they differ in size, physiology,
appearance, and life history. The challenge for evolutionary biology is to explain how such …

The fitness function f relates fitness of individuals to the quantitative trait under natural
selection. The function is useful in predicting fitness differences among individuals and in …

There is now a good theoretical understanding of life history evolution, and detailed explicit
optimality models have been constructed. These present a challenge for empirical work …

(1) Brood reductions and enlargements were carried out in kestrel nests to evaluate the
consequences of raising different numbers of nestlings for both the offspring and the …

(1) Trade-offs between brood size and offspring growth and survival were studied by
manipulating the size of 221 great tit Parus major L. broods between 1983 and 1987.(2) …

1. The influence of reproductive effort on host susceptibility to parasitism was examined in
great tits, Parus major, by comparing the prevalence of haematozoan parasites with respect …

Birds experience strikingly different patterns of mass change during breeding. In some
species with uniparental incubation, the incubating parents (mostly females) lose mass and …

1. We tested for costs of chick rearing in the black‐legged kittiwake Rissa tridactyla
(Linnaeus) by removing entire clutches from 149 of 405 randomly selected nests, in which …

Meta—analysis is a method ecologists may find useful for quantitatively reviewing and
systematically examining results from a large number of studies on a subject for which there …