Project aimed at testing the maintenance and expression of environmentally acquired epigenetic variation under field conditions. A new epigenetic mechanism was discovered in the ISFH laboratory, but its relevance outside the laboratory was unknown. The experiment revealed epigenetic information maintained in microcosms that mimicked biotic and abiotic field conditions. However, temperature affected the expression of epigenetic variants. This work is the first to empirically validate the relevance of a new epigenetic system for Drosophila ecology and evolution.