Digit ratios have poor indicator value in a wild bird population

Personality and basal metabolic rate in a wild bird population

Heritable circadian period length in a wild bird population.

Timing is essential, but circadian clocks, which play a crucial role in timekeeping, are almost unaddressed in evolutionary ecology. A key property of circadian clocks is their free-running period length (τ), i.e. the time taken for a full cycle under constant conditions. Under laboratory conditions, concordance of τ with the ambient light-dark cycle confers major fitness benefits, but little i...

Sex differences in anogenital distances and digit ratios in wild David’s rock squirrels Sciurotamias davidianus

The prenatal hormonal environment plays an important role in organizing sex differences in the morphology, physiology and behavior of humans as well as other vertebrates. Currently, all related research on rodents has been focused on Myomorpha. This study presents data on sex differences in the anogenital distance (AGD) and the ratio of the second to the fourth digit length (2D:4D) from 44 wild...

The forms and fitness cost of senescence: age-specific recapture, survival, reproduction, and reproductive value in a wild bird population.

Longitudinal studies of senescence accumulate rapidly from natural populations. However, it is largely unknown whether different fitness components senesce in parallel, how reproductive and survival senescence contribute to declines in reproductive value, and how large the fitness cost of senescence is (the difference between the observed reproductive value and the hypothetical reproductive val...

Family-transmitted stress in a wild bird.

Recent data suggest that, in animals living in social groups, stress-induced changes in behavior have the potential to act as a source of information, so that stressed individuals could themselves act as stressful stimuli for other individuals with whom they interact repeatedly. Such form of cross-over of stress may be beneficial if it enhances adaptive responses to ecological stressors in the ...