biostudies-literatureAnttonen PGerman Center for Integrative Biodiversity Researchfinancial support from the DFG under the programme Open Access PublishingDeutsche Forschungsgemeinschaft1100https://www.ebi.ac.uk/biostudies/studies/S-EPMC9785672biostudies-literatureUnknown13(12)Nutritional content of host plants is expected to drive caterpillar species assemblages and their trait composition. These relationships are altered by tree richness-induced neighborhood variation and a seasonal decline in leaf quality. We tested how key functional traits related to the growth and defenses of the average caterpillar hosted by a tree species are shaped by nutritional host quality. We measured morphological traits and estimated plant community-level diet breadth based on occurrences from 1020 caterpillars representing 146 species in a subtropical tree diversity experiment from spring to autumn in one year. We focused on interspecific caterpillar trait variation by analyzing presence-only patterns of caterpillar species for each tree species. Our results show that tree richneInsectsLeaf Nutritional Content, Tree Richness, and Season Shape the Caterpillar Functional Trait Composition Hosted by Trees.PMC9785672DFG - FZT 118, 202548816319936945/GRK2324Wang MQLi YBruelheide HSchuldt AAnttonen PChesters DChen JTDavrinche AMa KPZhu CDHaider SfalseLeaf Nutritional Content, Tree Richness, and Season Shape the Caterpillar Functional Trait Composition Hosted by Trees.Nutritional content of host plants is expected to drive caterpillar species assemblages and their trait composition. These relationships are altered by tree richness-induced neighborhood variation and a seasonal decline in leaf quality. We tested how key functional traits related to the growth and defenses of the average caterpillar hosted by a tree species are shaped by nutritional host quality. We measured morphological traits and estimated plant community-level diet breadth based on occurrences from 1020 caterpillars representing 146 species in a subtropical tree diversity experiment from spring to autumn in one year. We focused on interspecific caterpillar trait variation by analyzing presence-only patterns of caterpillar species for each tree species. Our results show that tree richne2022-01-01T00:00:00Z2022 Nov2025-04-04T08:00:31.518Z2025-04-04T08:00:31.518ZS-EPMC97856723655501010.3390/insects13121100