A researcher working in the Riomar project shows a worm found in a sediment sample on board the Antedon II boat during a sea trip in the Rhone River delta in the Gulf of Lion near Marseille on September 25, 2024. The Riomar project studies the evolution of the coastal environment under the influence of rivers in five metropolitan coastal areas to observe and model the coastal environment at the mouths of French rivers. (Photo by DAVID COSTA / AFP)