Aging below ground: Lifespan-resolved transcriptional dynamics in a dominant soil invertebrate model

The aging of individual organisms is a fundamental yet little explored driver of biodiversity and population dynamics. While aging has been extensively studied in various laboratory models, its molecular basis in natural ecosystems remains poorly understood. Soil, the most biodiverse habitat on Earth, hosts a vast array of species whose aging processes are largely unknown. Here, we describe a lifespan-resolved transcriptional analysis of aging in Enchytraeus crypticus, a dominant soil invertebrate. By tracking gene expression across the full lifespan, we revealed age-associated molecular dynamics, also linked to reproductive decline. These findings demonstrate how individual-level aging trajectories can shape population-level outcomes. Our study establishes E. crypticus as a valuable model for aging research and highlights the ecological relevance of understanding aging at the level of the individual organism.