Added the function extractPredictiveData() to perform a posterior predictive model-checking procedure. Implemented code coverage and unit test. Improved the code (to make it clearer, considering width and the assignment operator). Changed some arguments (consumer instead of species, group instead of community and others) in loadIsotopeData(), extractIsotopeData() and other functions (while maintaining old arguments as compatibility) Added a a procedure for checking errors on priors arguments in jagsBayesianModel and related functions Removed MCMCvis from the Short guide to tRophicPosition vignette, as that package is no longer in CRAN.