 They are important decomposers, breaking down organic materials, such as dead leaves and animals, and helping the detritivores (animals that feed on decomposing material) to obtain their nutrients.Ascomycetes along with other fungi can break down large molecules such as cellulose or lignin, and thus have important roles in nutrient cycling such as the carbon cycle.The fruiting bodies of the Ascomycota provide food for many animals ranging from insects and slugs and snails ("Gastropoda") to rodents and larger mammals such as deer and wild boars.