Figures and Tables Legends
Figure 1 – Framework used in this study. Liana species (woody climbers) may be classified into two main types of climbing on supports: passive and active mechanisms. Each group has different types of strategies (see explanation in Box 1). The upper blue arrow indicates an increase in complexity of the type of climbing mechanism from scrambler to tendril. The lower blue arrow indicates an increase in the maximum size (diameter) of the support to which each type of climbing mechanism can attach. Note that the constraint in size support is valid only for species with active climbing since species with passive climbing do not climb and pass over different supports.
Figure 2 – Functional trait differences among liana species per climbing mechanism type (a-f) based on synthesis from literature. Note that leaf area (d) and seed mass (f) are in the logarithmic scale.
Figure 3 – Results from the piecewise structural equation models for abundance of active and passive climbing species across the tropics. In (a), structural equation model explaining liana density per plot of the active climbing species in relation to forest structure, climate and soils. In (b), structural equation model explaining liana density per plot of the passive climbing species in relation to forest structure, climate and soils. TEMP = temperature; PREC = precipitation; and CEC = cation exchange. Transparent arrows represent non-significant coefficients and dashed arrows represent marginally significant coefficients (0.05 < P < 0.1). Density is the number of individuals per ha. The inset map shows the location of the plots used in this study.
Figure 4 – Results from the piecewise structural equation models for richness of active and passive climbing species across the tropics. In (a), structural equation model explaining liana species richness per plot of the active climbing species in relation to forest structure, climate and soils. In (b), structural equation model explaining liana species richness per plot of the passive climbing species in relation to forest structure, climate and soils. TEMP = temperature; PREC = precipitation; and CEC = cation exchange. Transparent arrows represent non-significant coefficients and dashed arrows represent marginally significant coefficients (0.05 <P < 0.1). Species richness is the number of species per ha. The inset map shows the location of the plots used in this study.
Figure 5 – Map showing the relative proportion of species richness per climbing mechanism across biogeographical realms. Note that the relative proportion of active to passive climbing species richness is significantly higher in the Neotropics (Table S1).