Enamel_Sr support the data intake, processing, statistical analyses, and modeling components of the pre-print article entiled "Multi-substrate and micro-sampling analyses reveal spatial patterns of strontium isotope turnover in elephant molar enamel". The JAGS models made the following major improvements over the original BITS framework: 1) it allows the model to be run more efficiently with rate scaling and bin thinning; 2) it allows the user to define the growth rate to sampling distance relationship to accommodate the logarithmic growth pattern of molar enamel and dentine.
There are four primary data files associated with this study. They are in the root directory with "data XX" in the file names with short descriptions. The "data" folder contains raw data only, which includes LA-ICP-MS, micromilled, and hand drilled enamel and dentine data used in this study, as well as laser log files and published data from Yang et al., 2023 to support the analyses and plots associated with the article.
The code was developed in R (ver. 4.3.1) calling the standalone JAGS (Just Another Gibbs Sampler) program, which is required before the code can be run. The JAGS program can be downloaded via this link. Please make sure to download the version that is appropriate for your operating system.
To call JAGS from RStudio, the R packages "R2jags" are also required.
Other R packages specified in the file headers help to visualize data.
Yang et al., (2023). BITS: a Bayesian Isotope Turnover and Sampling model for strontium isotopes in proboscideans and its potential utility in movement ecology. Methods in Ecology and Evolution. https://besjournals.onlinelibrary.wiley.com/doi/10.1111/2041-210X.14218
Yang, D. BITS: Bayesian Isotope Turnover and Sampling model. https://doi.org/10.5281/zenodo.7768584
Yang, D. (2024), Enamel_Sr. https://github.com/Deming-Yang/Enamel_Sr