Sexual dimorphism in pheromone perception across worms, flies, and rodents

Sex-specific chemosensory behaviors arise from differences in how males and females detect and process environmental chemical cues, including pheromones, which drive sex-appropriate behaviors essential for reproduction across many species. This review compares neural circuits in Caenorhabditis elegans, Drosophila, and rodents that generate sexually dimorphic pheromone responses, spanning peripheral detection, relay centers, and central integration. Recent connectomic and circuit-level analyses reveal how internal states modulate these pathways, adding an additional layer of context-dependent, sex-specific modulation. By synthesizing mechanisms across species, we highlight conserved principles and lineage-specific adaptations, offering an integrative framework for understanding how sex differences are embedded in chemosensory neural systems and setting the stage for future work on sexually dimorphic behaviors.