Fossilised faeces (coprolites) are overlooked in palaeontology but they reveal crucial information on the ecology and evolution of the animals that produced them and on their ecological and environmental interactions. Coprolites yield micro-remains of various digested species and provide unique insights into the paleofauna, paleoenvironment and trophic webs. The Carboniferous-Permian transition records shifts from humid to arid global climates in continental environments (including lakes). However, it is still unclear how life has adapted to these changes. Coprolites from lacustrine deposits of French continental basins will be studied using high-resolution methodologies (PPC-SRμCT) to analyse their content and internal structure. The detailed 3D reconstructions of these Permo- Carboniferous coprolites produced by continental animals (freshwater fish or terrestrial tetrapods living in or around the lake) will allow us to better understand this important ecological turnover.