'Xega' Island Models // Implements asynchronous message-passing communication protocols for island models of extended and evolutionary algorithms (see Tomassini, Marco (2005, ISBN:978-3-540-24193-5)) for the R-package 'xega' https://CRAN.R-project.org/package=xega. Basic asynchronous as well as synchronized communication primitives are supplied based on file I/O operations ('rds') on a shared file system or by 'openMPI' (MPI) messages. The gene selection and replacement strategies, the migration policy as well as the communication topology between islands are configurable. Homogeneous and heterogeneous island algorithms are supported. For examples (R and shell-scripts), see https://github.com/agey erschulz/xega/tree/main/examples/IslandModels.