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Summary Historically, ferns have been described as underutilized by insects. However, studies have shown a diversity of insects interacting with ferns, although the evolutionary and ecological drivers of these interactions are still to be untangled. To fill these gaps, we compiled more than 100 yr of global data on insect–fern interactions from the literature comprising 374 fern and 649 insect species. With this database we assessed how fern trophic specialization, phylogenetic relationships and climate have shaped their interactions with insects. Our findings showed that interactions between ferns and insects can be explained by the phylogenetic relations among them. We observed that insect orders part of the Endopterygota clade tend to interact with similar fern species, which might be a result of the inheritance of Endopterygota ancestors probably due to phylogenetic niche conservationism. Under an ecological context, fern specialization increased with temperature, precipitation, and climatic stability. Our results show that climate might be one of the main factors explaining the spatial variation of insect–fern interactions, postulate also supported by the observed phylogenetic clustering of the studied ferns species. Our study highlights the intricate and multifaceted nature of insect–fern interactions, where evolutionary history and ecological factors converge to shape these relationships. [ABSTRACT FROM AUTHOR]

• Azteca chartifex decreased leaf herbivory and increased B. sericea flower-fruit conversion irrespective of lianas presence. • A positive effect of ants was detected only in the second year of the experiment, consistently on all plants at each experimental level. • Liana removal had no effect on A. chartifex foraging and on leaf herbivory and flower-fruit conversion of host plants. • Dominant arboreal ants can benefit plants even in a non-obligatory interaction. Tropical tree-climbing lianas form paths that benefit foraging of dominant ants which might protect the host tree against herbivores. In contrast, lianas are often associated with negative effects on growth and reproduction of host trees due to light obstruction, structural stress and other negative effects. It is unclear if dominant ants could mitigate the negative effects of lianas on host plants. We investigated how lianas and carton nest ants (Azteca chartifex) affected herbivory and reproductive structures of the host tree Byrsonima sericea. Considering 68 trees, almost half of them were naturally colonized by A. chartifex nests (32 trees). We removed lianas from half of the trees (34), establishing a factorial sampling design between A. chartifex and liana presence. We sampled ants and leaf herbivory before and after removing lianas, and measured plant fitness in two consecutive years after removing lianas. Liana removal had no effect on A. chartifex foraging, on leaf herbivory and flower-fruit conversion of host plants. However, A. chartifex decreased leaf herbivory and increased B. sericea flower-fruit conversion irrespective of lianas presence. A noticeable positive effect of ants was detected only in the second year of the experiment, consistently on all plants at each experimental level. The reproductive conditions of the first year resulted in most plants with more than 75% flower-to-fruit conversion success, regardless of the presence of A. chartifex , a success sustained only on those ant-colonized plants in the second year. Our results contribute to understanding multi-trophic interactions in tropical forest canopies as we demonstrated i) that dominant arboreal ants can benefit plants even in a non-obligatory interaction and ii) that the influence of lianas on its host tree is context-dependent, presenting even neutral effects depending on habitat type and species involved. [ABSTRACT FROM AUTHOR]

Environmental impacts of conventional agriculture have generated interest in sustainable agriculture. Biological pest control is a fundamental tool, and ants are key players providing ecological services, as well as some disservices. We have used a meta-analytical approach to investigate the contribution of ants to biological control, considering their effects on pest and natural enemy abundance, plant damage and crop yield. We also evaluated whether the effects of ants are modulated by traits of ants, pests and other natural enemies, as well as by field size, crop system and experiment duration. Overall (considering all meta-analyses), from 52 studies on 17 different crops, we found that ants decrease the abundance of non-honeydew-producing pests, decrease plant damage and increase crop yield (services). In addition, ants decrease the abundance of natural enemies, mainly the generalist ones, and increase honeydew-producing pest abundance (disservices). We show that the pest control and plant protection provided by ants are boosted in shaded crops compared to monocultures. Furthermore, ants increase crop yield in shaded crops, and this effect increases with time. Finally, we bring new insights such as the importance of shaded crops to ant services, providing a good tool for farmers and stakeholders considering sustainable farming practices. [ABSTRACT FROM AUTHOR]

Understanding the impacts of edge effects on ecological interactions plays an integral role in planning ecosystem recovery from human perturbations, as well as conservation of habitats. Edge effects related to forest fragmentation cause changes in species diversity that can disrupt ecological networks. Here, we evaluated how the diversity of, and interactions between, herbivorous insects associated with individuals of a pioneer plant species, Mabea fistulifera (Euphorbiaceae) are affected by the disturbances related to edge effects. We addressed two specific questions: (i) How do the forest edges affect species richness, abundance and composition of herbivorous interacting with M. fistulifera? (ii) Do different disturbances related to edge effects affect the topology of individual‐based plant‐herbivorous networks? Herbivorous insects were sampled from three population patches of M. fistulifera in Brazilian Atlantic forest areas: two areas were subjected to distinct intensities of anthropogenic disturbances (firebreak and park access road, considered edges of low‐ and high‐impact, respectively), and one in the forest interior (control). We expected a lower species richness and abundance of herbivorous interacting with plants in forest edges than in the forest interior apart from to differences in the species composition. Therefore, based on these predictions, we expected that the various disturbances related to edge effects may change the topology of individual‐based plant‐herbivorous networks. We observed that species richness and abundance of herbivorous in high‐impact environments decreased in relation to forest interior, as well the species composition differed between these areas. Disturbance jeopardised network specialisation but did not change the topology of individual‐based networks, which presented a modular pattern. Edges affected herbivorous diversity and decreased the interaction overlap as individual‐based networks became highly specialised with increasing disturbance. These results enhance the understanding of edge effects and resilience of plant‐herbivorous interactions in regularly disturbed tropical environments. [ABSTRACT FROM AUTHOR]