Data from: Antibiotics as chemical warfare across multiple taxonomic domains and trophic levels

Bacteria and fungi secrete antibiotics to suppress and kill other microbes, but can these compounds be agents of competition against macroorganisms? We explore how one competitive tactic, antibiotic production, can structure the composition and function of brown food webs. This aspect of warfare between microbes and invertebrates is particularly important today as antibiotics are introduced into ecosystems via anthropogenic activities, but the ecological implications of these introductions are largely unknown. We hypothesized that antimicrobial compounds act as agents of competition against invertebrate and microbial competitors. Using field-like mesocosms, we tested how antifungal and antibacterial compounds influence microbes, invertebrates, and decomposition in the brown food web. Both antibiotics changed prokaryotic microbial community composition, but only the antibacterial changed invertebrate composition. Antibacterials reduced the abundance of invertebrate detritivores by 34%. However, the addition of antimicrobials did not ramify up the food web as predator abundances were unaffected. Decomposition rates did not change. Our results show that antibiotic compounds could be an effective weapon for microbes to compete against both microbial and invertebrate competitors. In the context of human introductions, the detrimental effects of antibiotics on invertebrate communities indicates that the scope of this anthropogenic disturbance is much greater than previously expected.Invertebrate_Abundance_Data This file contains the raw data and associated metadata for all invertebrate abundance counts. weighted_unifrac_dm Prokaryotic Unifrac Distance Matrix used for PERMANOVA analyses. Prokaryotic_NMDS_File Prokaryotic NMDS scores and associated metadata. NMDS_File.csv Microbial BIOM File otu_table_meso_only.biom SurvivalAnalysis_ProcB R code for survival analysis and plotting. MesocosmInvertCode R code for invertebrate analyses. QiimeCodeForSequences Qiime code for generating biom table and initial analyses. MillipedeIsopod_Survival_RawData Raw data for the survival analysis of isopods and millipedes