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Abstract Determining the factors affecting the structure of insect herbivore communities is a major challenge in ecology. Previous research demonstrated that plant defenses determine plant‐herbivore associations. However, non‐defensive variables may also explain why some plant species are associated with more diverse insect herbivore assemblages than others. Neotropical rolled‐leaf beetles (CephaloleiaandChelobasis) complete their life cycle inside the young rolled leaves of their host plants in the order Zingiberales. The diet breadth of each species in this assemblage is particularly well‐known at our study site, La Selva Biological Station in Costa Rica. This study focused on the following non‐defensive variables: host plant elevational and geographic range size, soil type, habitat, local abundance, plant size, and leaf size. Because plant characteristics among closely related plants are not independent, we analyzed these variables in a phylogenetic context. We detected a positive effect of leaf width on rolled‐leaf beetle species richness (explaining 55% of the variation), abundance (28% of the variation and 57% when habitat is included in the model), diversity (37% of the variation), and community structure (6% of the variation, and 21%–26% when taxonomic family is included in the model). Our study demonstrates that Zingiberales leaf width influences positively rolled‐leaf beetle species richness, abundance, and diversity. This effect varies among plant families. Our study shows that plant architecture plays an important role in structuring insect herbivore assemblages in Zingiberales. Our results highlight the importance of including variables beyond plant defenses to understand the ecology and evolution of plant‐herbivore interactions. 

Abstract Field measurements demonstrate a carbon sink in the Amazon and Congo basins, but the cause of this sink is uncertain. One possibility is that forest landscapes are experiencing transient recovery from previous disturbance. Attributing the carbon sink to transient recovery or other processes is challenging because we do not understand the sensitivity of conventional remote sensing methods to changes in aboveground carbon density (ACD) caused by disturbance events. Here we use ultra-high-density drone lidar to quantify the impact of a blowdown disturbance on ACD in a lowland rain forest in Costa Rica. We show that the blowdown decreased ACD by at least 17.6%, increased the number of canopy gaps, and altered the gap size-frequency distribution. Analyses of a canopy-height transition matrix indicate departure from steady-state conditions. This event will initiate a transient sink requiring an estimated 24–49 years to recover pre-disturbance ACD. Our results suggest that blowdowns of this magnitude and extent can remain undetected by conventional satellite optical imagery but are likely to alter ACD decades after they occur.