Sticky Innovation, Limited Expansion: Biogeography and Evolutionary Ecology of Toepads in Geckos

ABSTRACT Aim This study investigates the evolutionary diversification and ecological significance of adhesive toepads in geckos. It examines how different toepad configurations (absent, basal, distal and fanlike) have evolved and relate to macroecological patterns. By analysing variation beyond mere presence or absence, it provides a finer‐scale understanding of toepad evolution and its links to climate, habitat and biogeographic history. Location Global. Major Taxa Studied Gekkota. Methods Toepad types were assigned based on species descriptions. An ultrametric phylogeny was pruned and calibrated for ancestral state reconstruction via stochastic character mapping. Species distribution, habitat and climate data were compiled from global databases and analysed in R. Species richness, habitat associations and climatic niche space were analysed in relation to toepad configuration. Results Toepad configurations are unevenly distributed across gekkotans, with padlessness reconstructed as the ancestral and most common state. Transitions between configurations occurred frequently, including secondary pad loss. Geographic distributions and climatic niche space differ by pad type, with padless species occupying the broadest and most variable conditions. Habitat associations also vary among configurations, with forest being the dominant habitat category across all groups. Main Conclusions This study confirms padlessness as the ancestral condition and highlights multiple origins of adhesive toepads. While transitions from padless to basal pads are most frequent, transitions from distal to basal pads are also supported. Climatic niche analysis shows that toepads do not grant access to new climate zones but reflect fine‐scale ecological adaptations, particularly to structurally complex habitats. Toepad configurations appear to facilitate ecological diversification within biomes. Geographic patterns seem more influenced by biogeographic history than direct climatic filtering, underscoring the role of historical contingency in shaping functional diversity.