Early-life conditions are crucial determinants of phenotype and fitness. The effects of pre- and post-natal conditions on fitness prospects have been widely studied but their interactive effects have received less attention. In birds, asynchronous hatching creates challenging developmental conditions for the last-hatched chicks, but differential allocation in last-laid eggs might help to compensate this initial handicap.
View Article and Find Full Text PDFIn addition to direct mortality, predators can have indirect effects on prey populations by affecting prey behaviour or physiology. For example, predator presence can increase stress hormone levels, which can have physiological costs. Stress exposure accelerates the shortening of telomeres (i.
View Article and Find Full Text PDFEnvironmental shifts may induce sudden reversals in the relative quality or sexual attractiveness of mates (ecological crossovers) leading to non-directional sexual selection. Studies on such ecological crossovers induced by environmental shifts during the nonbreeding season are particularly rare. We studied the interactive effects between nonbreeding conditions and a male white wing patch on the breeding success of breeding pairs and the local survival of females in a migratory passerine population over a 32-year period.
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