Macroevolution of floral scent chemistry across radiations of male euglossine bee-pollinated plantsMacroevolución de olores florales a través de radiaciones de plantas polinizadas por abejas euglosinas machosMacroevolução dos voláteis florais em radiações de plantas polinizadas por machos de abelhas Euglossini

This article focuses on the evolution and variation of floral volatile compounds in "perfume flowers," a group of Neotropical plants exclusively pollinated by male euglossine bees that collect floral scents as chemical rewards. By compiling and analyzing chemical data from 175 plant species across multiple families, the study identifies major axes of scent variation primarily driven by dominance of either terpenoid or phenylpropanoid (aromatic) biosynthetic pathways, with further variation influenced by specific monoterpenoid compounds such as 1,8-cineole and carvones. Phylogenetic analyses within two independent orchid radiations (the Catasetinae and Stanhopeinae) reveal rapid and divergent evolution of floral scent profiles, low phylogenetic signal for most scent traits, and evidence of chemical convergence across distantly related taxa. These patterns suggest that pollinator-mediated selection, particularly by euglossine bees with rapidly evolving olfactory preferences, plays a significant role in shaping floral scent diversity and may contribute to reproductive isolation and speciation in these plants.