Data from: Prenatal maternal effects appear to be insensitive to experimental or natural environmental variation

1. In many birds, hatching asynchrony is a common phenomenon, primarily driven by patterns of incubation behaviour. However, experimental results in blue tits (Cyanistes caeruleus) have shown that asynchrony is reduced by intrinsic properties of later eggs that accelerate pre-natal development. 2. These intrinsic differences between early and late eggs could be driven by changes in resource availability to females, which are then passively passed onto the egg. Alternatively, it may be due to an anticipatory maternal effect, wherein some signal or resource is actively placed within the egg, which is beneficial to those eggs laid late within the clutch. 3. In order to distinguish between these hypotheses we designed a supplementary feeding experiment, wherein females were provided with food at certain times during the laying phase. This had no discernible effect on development rate, or other egg characteristics, consistent with anticipatory maternal effects. 4. Using a larger data set we also tested whether natural environmental variation (weather) during egg formation affected maternal investment in eggs. Similarly, egg characteristics were found to be relatively insensitive to the environmental variation, supporting the experimental results.tEGGSData containing information about individual eggs within all nests in the years included in the feeding experiment (to analyse hatching time, hatching asynchrony, weight, and hatching success)., as well as information about the feeding treatments of those nests.NewdatData containing all eggs in experimental years (as with data frame tEGGS), augmented with those eggs that were not laid (during interruptions in the laying sequence)dfNest-level data of those years included in the feeding experimenttEGGSallData frame of all eggs included in main weather analyses (hatching time, hatching asynchrony, weight, and hatching success).tEGGSall.augData of all eggs included in the weather analysis, augmented to include those eggs that were not laid (in laying interruptions). Used for pausing analysis.dfallNest level data for all years included in the weather analyses.FeedingModelsScriptR Script for models used to analysis the feeding experimentSpline.FunctionsR Script for setting up varying coefficient splines used in modelsWeather-CGHR Script for carrying out the hatching time analysis on the effects of weatherWeather-ORDHR Script for carrying out the hatching asynchrony (ordinal hatching day) analysis on the effect of weatherWeather-HATSR Script for analysis of the effect of weather on hatching successWeather-WGHTR Script for the analysis of the effect of weather on egg weightWeather-PSER Script for the analysis of the effect of weather on the probability of an egg being laid (pausing analysis)Weather-CSIZER Script for the analysis of the effect of weather on clutch sizeWeather-INCR Script for the analysis of the effect of weather on incubationFeeding-CGH-KExample R script for carrying out K-fold cross-validation of the models. In this case, it is for the model of the effect of the feeding treatment on hatching time (censored Gaussian)