A Toolbox for Modelling Species Coexistence in R R package cxr version 1.1.1 Recent developments in modern coexistence theory have advanced our understanding on how species are able to persist and co-occur with other species at varying abundances. However, applying this mathematical framework to empirical data is still challenging, precluding a larger adoption of the theoretical tools developed by empiricists. This package provides a complete toolbox for modelling interaction effects between species, and calculate fitness and niche differences. The functions are flexible, may accept covariates, and different fitting algorithms can be used. A full description of the underlying methods is available in García-Callejas, D., Godoy, O., and Bartomeus, I. (2020) <doi:10.1111/2041-210X.13443>. Furthermore, the package provides a series of functions to calculate dynamics for stage-structured populations across sites. Software Depends: R (>= 3.5) Imports: Matrix, mvtnorm, optimx, stats Suggests: BB, DEoptimR, dfoptim, dplyr, GenSA, ggplot2, knitr, magrittr, minqa, nloptr, rmarkdown, stringr, testthat (>= 0.8.0), tidyr, ucminf David Garcia-Callejas <david.garcia.callejas@gmail.com> Comprehensive R Archive Network (CRAN) David Garcia-Callejas [aut, cre] (ORCID: <https://orcid.org/0000-0001-6982-476X>), Ignasi Bartomeus [aut] (ORCID: <https://orcid.org/0000-0001-7893-4389>), Oscar Godoy [aut] (ORCID: <https://orcid.org/0000-0003-4988-6626>), Maxime Lancelot [ctb], Maria Paniw [ctb] MIT + file LICENSE (https://CRAN.R-project.org/package=cxr/LICENSE) 2023-10-26 application/tgz https://CRAN.R-project.org/package=cxr doi:10.32614/CRAN.package.cxr