Many studies have analysed how variability in reproductive success affects fitness. However, each study tends to focus on a particular problem, leaving unclear the overall structure of variability in populations. This fractured conceptual framework often causes particular applications to be incomplete or improperly analysed. In this article, I present a concise introduction to the two key aspec...

1. Longitudinal studies of various vertebrate populations have recently demonstrated senescent declines in reproductive performance and/or survival probability with age to be almost ubiquitous in nature. Little is known, however, about the extent to which rates of senescence vary between individuals, and about causes or consequences of such variation. Quantifying these links in natural populati...

We tested for negative effects of West Nile virus (WNV) on a breeding population of eastern bluebirds in Alabama by comparing fecundity and reproductive success in years before and after the arrival of WNV and by comparing fecundity, reproductive success, and overwinter survival of seropositive and seronegative individuals within the same population in the same years. We found that female blueb...

Several nonexclusive, sometimes contradictory, hypotheses have been employed to explain age-related changes in reproduction and survival among vertebrates. We evaluated these hypotheses with observations collected from a 31-year study of individually marked Wood Thrushes (Hylocichla mustelina). Age-specific fledgling production, survival probabilities, and derived life table columns are present...

1. For iteroparous organisms life-history theory predicts a trade-off between current and future reproduction, and therefore the evolution of host responses to current parasite infestation that will maximize lifetime reproductive success. The parasite-induced variation in reproductive success is thus not the net result of parasite infestation alone, but the parasite-mediated outcome of optimal ...

Evolutionary psychology, memetics and models of cultural evolution focus on reproductive success. I will argue that fitness should in fact focus on differential persistence of entities instead of differential reproductive success of replicators. Understanding evolution as such shifts the nature of adaptation from reproduction to persistence, changing the means by which representational powers w...

You might have heard that dedication and perseverance are important elements for success. This is particularly true science, specifically the study of animal behavior. Collecting biological data decades can help scientists to better understand slow environmental changes their consequences. For instance, globally increasing temperatures may affect behavior reproduction. We investigated if how ch...

Modelling territorial occupancy and reproductive success is a key issue for better understanding the population dynamics of territorial species. This study aimed to investigate these ecological processes in a Eurasian Eagle-owl (Bubo bubo) population in south-eastern Spain during a seven-year period. A multi-season, multi-state modelling approach was followed to estimate the probabilities of oc...