Data used in the article
One but not two grandmothers increased child survival in poorer families in west Bohemian population

Human childrearing is characterized by cooperative care and grandmothers are usually the most prominent alloparents. Nevertheless, it has been argued that limited resources may intensify competition among kin. The effect of grandmothers’ presence on child survival may thus crucially depend on the family’s socioeconomic status. We evaluate the impact of grandmothers’ presence on child survival using a large historical dataset from eighteenth to nineteenth-century western Bohemia (N = 6880) and assess the effects of socioeconomic status. We employed a varying effects model conditioned on relatedness between individuals because of possible genetically transmitted benefits. Proportional hazards showed that grandmothers had little or no impact on child survival in families of high and medium socioeconomic status (farmers and cottagers, respectively), while in families with the lowest socioeconomic status (lodgers), grandmothers’ presence increased the survival probability of children up to five years of age. The beneficial effect of grandmaternal care was strongest between the first and second year of life. Importantly, though, in families with low socioeconomic status, we also observed lower survival chances of children when both grandmothers lived in the same village. These findings suggest that the balance between kin cooperation in childrearing and competition over resources may depend on resource availability.

The data were digitalized from historical curch records by a group of experts led by Alice Velková. The parent-children pairs were identified on the basis of names, residence sites and dates of births/deaths. Incomplete or corrupted data were excluded. Details can be found in the manuscript or on a GitHub page: https://github.com/costlysignalling/CharlieBucket
See attached scripts for the complete analysis and data handling record.

Code and data used in the analysis of grandmaternal presence and gradchild survival in West Bohemia 18-19th century. You can fit the model from 02_Model_MCMC.R, if you are interested in how data is handeled, check 01_data_handle_by_month.R. This script sources additional code from 00_arrange_data_sample.R. The model is summarized and the results are visualized using 03_visualizations_and_summary.Rmd. In any case it is advisable to start the anlysis from the final.Rproj project file that sets the essentials like working directory and encoding.

source_data.txt contains crucial information about the studied children.
pedigree_data.txt contains the relatedness information about the whole population that can be used to construct the relatedness matrix.
key_places.txt contains information about residences and tolerated forms of settlement names in the dataset.
distances.txt contains a distance matrix of the settlements based on current GPS data. source_data.GM.txt is an extra file that contains additional information on grandmothers. This is used only to calculate descriptive statistics about the grandmothers.
complete_families is an additional, differently structured dataset, that contains data on reconstructed families, where all children were identified. This was used to calculate descriptive statistics by families (total number of children, the onset of reproduction etc.) Each person in the database is assigned a unique code, so information on a single person can be stored in more than one dataset.

All data files contain tab-separated values.