Director of Research at the CNRS (Centre National de la Recherche Scientifique) Olivier Guillaume poses in the Moulis caves where underground aquatic species are bred and studied in Moulis, southwestern France on July 8, 2026. France and the Parc naturel regional des Pyrenees Ariegeoises are implementing a project to classify its caves and underground rivers as a reserve in order to ensure better preservation of this subterranean heritage, to facilitate scientific and technical studies, and to increase awareness-raising activities in environmental education and sustainable development. (Photo by Lionel BONAVENTURE / AFP via Getty Images)