Evolving the structure: climatic and developmental constraints on the evolution of plant architecture. A case study in <i>Euphorbia</i>

Plant architecture strongly influences ecological performance, yet its role in plant evolution has not been explored depth. By testing both phylogenetic and environmental signals, it is possible to separate architectural traits into four categories: development constraints (phylogenetic signal only); convergences (environmental dependency key confluences the driver (both); unknown (neither). We analysed evolutionary history of genus Euphorbia, a model clade with high diversity wide range. conducted comparative analyses 193 Euphorbia species world-wide using 73 traits, dated phylogeny, climate data. identified 14 types based on trait combinations. found 22 three representing under groups, 21 showing but no relation climate, 16 five signals. Major drivers likely include water stress deserts (selected for succulence, continuous branching), frost disturbance temperate systems simple, prostrate, short-lived shoots) light competition arborescence). Simple architectures allowed resilience disturbance, frequent transitions new forms. Complex functional specialisation developed stable climates have low evolvability.