• Publications
  • Influence
Fitness consequences of avian personalities in a fluctuating environment
It is shown that selection on a personality trait with high heritability fluctuates across years within a natural bird population, and it is expected that the observed fluctuations in environmental factors lead to fluctuations in competition for space and food, and these, in association with variations in population density, lead to a variation in selection pressure, which maintains genetic variation in personalities. Expand
Warmer springs lead to mistimed reproduction in great tits (Parus major)
This work believes that this is the first documented case of an adaptive response being hampered because a changing abiotic factor affects the environment in which a reproductive decision is made differently from the environments in which selection occurs. Expand
Extreme adaptive modification in sex ratio of the Seychelles warbler's eggs
It is shown that biased hatching sex ratios are caused by biased production and not by differential embryo mortality, and that unhelped breeding pairs on low-quality territories produce 77% sons, whereas unhelping pairs on high- quality territories produce 13% sons. Expand
Pairs of extreme avian personalities have highest reproductive success
It is hypothesized that fast-exploring individuals are better able in defending or obtaining a high quality territory, while slow- Exploratory individuals are either better parents or have better chicks which may, in part, explain the patterns in reproductive success. Expand
Differential response by males and females to manipulation of partner contribution in the great tit (Parus major)
1. In birds with bi-parental care, handicapping is often assumed to decrease the amount of parental care of the handicapped partner. We discuss how handicapping could alter the shape of theExpand
Nestling Weight and Survival in Individual Great Tits (Parus major)
It is concluded that weight does play a causal role in this relationship between recapture rate and nestling weight in individual great tits and that this relationship can be estimated from non-experimental data. Expand
Parental energy expenditure during brood rearing in the Great Tit (Parus major) in relation to body mass, temperature, food availability and clutch size
Analysis of intraspecific variation in DEE(par) for 10 species tending young, revealed variable trends with body mass, which accounted for the differences found between years and broods and explained 64% of the variation. Expand
Seasonal Decline in Reproductive Success of the Great Tit: Variation in Time or Quality?
It is concluded that seasonal declines in reproductive success at the nestling stage and survival of adult females were caused by differences in quality between early and late breeders, and recruitment of fledglings into the breeding population and the occurrence of second clutches were causally related to the timing of breeding. Expand
Evolutionary signals of selection on cognition from the great tit genome and methylome
The high-quality great tit genome assembly is assembled, showing an overrepresentation of genes related to neuronal functions, learning and cognition in regions under positive selection, as well as increased CpG methylation in these regions. Expand
Family Planning in the Kestrel (Falco tinnunculus): The Ultimate Control of Covariation of Laying Date and Clutch Size
Plasma prolactin data of female kestrels show that this hormone is a serious candidate for a physiological component relaying time of year in the authors' model for clutch size regulation, which incorporates an increasing tendency to incubate the first eggs with progression of the season. Expand