Agricultural landscapes reshape progeny through transcriptomic and physiological changes.

Agricultural expansion is one of the leading causes of biodiversity loss, yet the molecular and physiological mechanisms linking habitat modification to individual state remain understudied. Identifying mechanisms underlying organisms' responses to habitat modification is essential for accurately modelling cause-effect relationships. Using transcriptomics and blood-based assays, we show that young European rollers (Coracias garrulus) raised in cropland-dominated landscapes (CL) have nine genes significantly downregulated compared to conspecific young birds raised in mixed-use landscapes (mosaics of land uses including meadows, pastures, and fallows; ML), with overrepresented genes in the catalase complex, a key antioxidant system. Consistent with gene expression results, CL birds showed lower blood catalase activity than ML birds. CL birds also exhibited higher glutathione peroxidase activity and lower immunoglobulin Y than ML birds. Finally, we found no differences in SOD activity, DNA damage, haptoglobin, BKA, haemagglutination, and haemolysis between habitats. Overall, our results reveal small molecular and physiological differentiation between CL and ML habitats, primarily driven by specific components of immune-oxidative physiology. This study provides novel mechanistic insights into how habitat conditions can influence organisms during early life stages.