Data from: Nest size is predicted by female identity and the local environment in the blue tit, but is not related to genetic or foster mother's nest size

The potential for animals to respond to changing climates has sparked interest in intraspecific variation in avian nest structure since this may influence nest microclimate and protect eggs and offspring from inclement weather. However, there have been relatively few large-scale attempts to examine variation in nests or the determinates of individual variation in nest structure within populations. Using a set of mostly pre-registered analyses, we studied potential predictors of variation in the size of a large sample (803) of blue tit (Cyanistes caeruleus) nests across three breeding seasons at Wytham Woods, UK. Whilst our pre-registered analyses found that individual females built very similar nests across years, there was no evidence in follow-up (post hoc) analyses that their nest size correlated to that of their genetic mother or, in a cross-fostering experiment, to the nest where they were reared. In further pre-registered analyses, spatial environmental variability explained nest size variability at relatively broad spatial scales, and especially strongly at the scale of individual nestboxes. Our study indicates that nest structure is a characteristic of individuals, but is not strongly heritable, indicating that it will not respond rapidly to selection. Explaining the within-individual and within-location repeatability we observed requires further study.

Usage Notes
Final blue tit nest size dataNest sizes recorded by SCG in Wytham Woods, UK 2001-2003. Nest sizes were recorded as fraction of standardised nest box filled. Blue tits were identified using uniquely marked metal rings to give identities. Zone is the woodland compartment in Wytham Woods where the nest is.Final BT nest data LON 2018-2-6.csvBlue tit nest sizes for genetic mother-daughter pairsNest sizes (recorded as fraction of standardised nest box filled) of blue tit daughters and their genetic mothers, as recorded by SCG in Wytham Woods, Oxfordshire, UK in 2001-2003genetic depth2.csvBlue tit nest sizes for foster mother-daughter pairs 2Nest sizes (recorded as fraction of standardised nest box filled) of daughters and their foster mothers, as recorded by SCG in Wytham Woods, UK during 2001-2003 breeding seasons. Rrearing depth2.csvFinal R code used for analysis 2The R code that I wrote to analyse different factors controlling the nest size of blue tits in Wytham Woods, UK during the 2001-2003 breeding seasons using the data files attachedFinal BT nest size analysis code.R

动物应对气候变化的潜力，引发了学界对鸟类巢筑结构种内变异的研究兴趣——此类变异可影响巢内微气候，保护卵与幼雏免受恶劣天气侵扰。然而，目前针对种群内巢筑结构变异，或是个体间巢筑结构差异决定因素的大规模研究仍相对匮乏。

本研究采用多数已预注册（pre-registered）的分析方案，对英国威瑟姆森林（Wytham Woods）三个繁殖季内、共计803个蓝山雀（Cyanistes caeruleus）巢的大小变异潜在影响因子展开探究。预注册分析结果显示，雌性个体每年筑造的巢大小极为相似；但后续事后（post hoc）分析未发现证据表明，其巢大小与其遗传母亲的巢大小存在关联，在交叉抚育（cross-fostering）实验中，也未发现其巢大小与抚育其成长的巢的大小存在相关性。进一步的预注册分析表明，空间环境变异可在相对较广的空间尺度上解释巢大小的变异，且在单个巢箱的尺度上，该解释效应尤为显著。

本研究表明，巢筑结构属于个体特征，但不具备强遗传性，这意味着其不会对选择产生快速响应。解释我们观测到的个体内与位置内的可重复性，仍需开展进一步研究。

使用说明
1. 最终蓝山雀巢大小数据集
2001-2003年，由SCG在英国威瑟姆森林记录的蓝山雀巢大小数据。巢大小以标准化巢箱的填充比例进行记录。蓝山雀通过带有唯一标识的金属脚环进行个体识别。"区域"指威瑟姆森林中该巢所在的林分区划。
数据集文件：Final BT nest data LON 2018-2-6.csv

2. 蓝山雀遗传母子对巢大小数据集
2001-2003年，由SCG在英国牛津郡威瑟姆森林记录的蓝山雀子代及其遗传母亲的巢大小数据（巢大小以标准化巢箱的填充比例记录）。
数据集文件：genetic depth2.csv

3. 蓝山雀寄养母子对巢大小数据集
2001-2003年繁殖季，由SCG在英国威瑟姆森林记录的蓝山雀子代与其寄养母亲的巢大小数据（巢大小以标准化巢箱的填充比例记录）。
数据集文件：Rrearing depth2.csv

4. 最终分析所用R代码
本研究编写的R代码，用于基于附件数据集，分析2001-2003年英国威瑟姆森林内影响蓝山雀巢大小的各类调控因子。
代码文件：Final BT nest size analysis code.R