Environmental contaminants are increasingly recognized as potential drivers of microbial adaptation. This study investigates whether two complex microbial traits, biofilm formation and polycaprolactone (PCL) degradation, are primarily driven by taxonomic affiliation or environmental exposure. A collection of bacterial strains was isolated from distinct environments, including poultry litter (antibiotics) and plastic-contaminated soils. Biofilm formation was quantified while PCL degradation was assessed via clearing-zone assays. Isolates from both taxonomic and metabolic perspective and multivariate analyses to explore the association between trait and environment. Biofilm formation was predominantly observed in multidrug-resistant strains from poultry farming, while PCL degradation was exclusive to strains from plastic-rich environments. Exposure to environmental pollution appears to promote the emergence of microbial traits through ecological selection and plastic responses.