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The diversity of fruits and frugivorous species is especially high in tropical regions where frugivory and seed dispersal interactions are particularly critical for the structure and functioning of terrestrial communities. However, the increasing urbanization in tropical areas has caused profound landscape changes, affecting species interactions and associated ecosystems functions. Here, we present an overview of the studies on frugivory and seed dispersal in tropical urban areas, discussing emergent patterns and processes underlying plant-frugivore interactions as well as major research gaps. Our review highlights an uneven geographical distribution of studies, which are more frequent in the Neotropics in comparison to Indomalayan and Afrotropical regions. We found that in tropical urban areas: (i) the most frequently studied group are flying frugivores (birds and bats), (ii) fruits of Myrtaceae, Moraceae, and Arecaceae are most frequently reported as consumed by frugivores, (iii) introduced plants are often present in frugivores’ diets, and become more common with urbanization, (iv) frugivores niche breadths vary with seasonality in fruit availability, (v) a higher diversity of fruits are consumed by frugivores in (or near) habitats that preserve more natural characteristics, such as higher proportion of green areas. Since suitable habitats within cities are highly variable in size, shape, connectivity, patterns of human activity, vegetation management and socioeconomic contexts, we recommend future studies to sample gradients in such variables. Furthermore, as new urban areas are often planned in advance, ‘before-after impact’ studies may be particularly insightful to understand how frugivores respond to urbanization and how to create frugivore-friendly areas without promoting undesirable (invasive) plants. Although the scarcity of studies and their geographical bias limit generalizations across distinct tropical regions, based on our review we provide a preliminary list of broad recommendations of management practices towards creating biodiversity-friendly urban areas.

Interaction network structure reflects the ecological mechanisms acting within biological communities, which are affected by environmental conditions. In tropical forests, higher precipitation usually increases fruit production, which may lead frugivores to increase specialization, resulting in more modular and less nested animal-plant networks. In these ecosystems, El Niño is a major driver of precipitation, but we still lack knowledge of how species interactions change under this influence. To understand bat-plant network structure during an extreme El Niño-Southern Oscillation event, we determined the links between plantivorous bat species and the plants they consume by DNA barcoding seeds and pulp in bat faeces. These interactions were recorded in the dry forest and rainforest of Costa Rica, during the dry and the wet seasons of an extreme El Niño year. From these we constructed seasonal and whole-year bat-plant networks and analysed their structures and dissimilarities. In general, networks had low nestedness, had high modularity, and were dominated by one large compartment which included most species and interactions. Contrary to our expectations, networks were less nested and more modular in drier conditions, both in the comparison between forest types and between seasons. We suggest that increased competition, when resources are scarce during drier seasons and habitats, lead to higher resource partitioning among bats and thus higher modularity. Moreover, we have found similar network structures between dry and rainforests during El Niño and non-El Niño years. Finally, most interaction dissimilarity among networks occurred due to interaction rewiring among species, potentially driven by seasonal changes in resource availability.

Encounters between flowers and invertebrates are key events for the functioning of tropical forests. Assessing the structure of networks composed by the interactions between those partners enables a better understanding of ecosystem functioning and the effects of environmental factors over ecological processes. Gathering such data is, however, costly and time-consuming, especially in the highly diverse tropics. We aimed to provide a comprehensive repository of the available flower-invertebrate interactions information for the Atlantic Forest, a South American tropical forest domain. Data were obtained from published works and "grey literature", such as theses and dissertations, as well as self-reports by co-authors. The data set has ~18 thousand interaction records forming 482 networks, each containing from 1 to 1,061 interaction links. Each network was sampled for about 200 hours or less, with few exceptions. A total of 641 plant genera within 136 different families and 39 orders were reported, with the most abundant and rich families being Asteraceae, Fabaceae and Rubiaceae. Invertebrates interacting with these plants were all arthropods from 10 orders, 129 families and 581 genera, comprising 2,419 morphotypes (including 988 named species). Hymenoptera was the most abundant and diverse order with at least six times more records than the second-ranked order (Lepidoptera). The complete data set shows Hymenoptera interacting with all plant orders, also depicting Diptera, Lepidoptera, Coleoptera, and Hemiptera as important nodes. Among plants, Asterales and Fabales had the highest number of interactions. The best sampled environment was forest (~8,000 records), followed by pastures and crops. Savanna, grasslands and urban environments (among others) were also reported, indicating a wide range of approaches dedicated to collect flower-invertebrate data in the Atlantic Forest domain. Nevertheless, most reported data were from forest understory or lower strata, indicating a knowledge gap about flower-invertebrate interactions at the canopy. Also, access to remote regions is still a limitation, generating sampling bias across the geographical range of the Atlantic Forest. Future studies in these continuous and hard to access forested areas shall bring important new information regarding the interactions between flowers and invertebrates at the Atlantic Forest. There are no copyright restrictions on the data set. Please cite this data paper if the data are used in publications and teaching events.

Individual behaviour and local context can influence the evolution of ecological interactions and how they structure into networks. In trophic interactions, consumers can increase their fitness by actively choosing resources that they are more likely to explore successfully. Mathematical modelling is often employed in theoretical studies to understand the coevolutionary dynamics between consumers and resources. However, they often disregard the individual consumer behaviour since the complexity of these systems usually requires simplifying assumptions about interaction details. Using an individual-based model, we model a community of several species that interact antagonistically. Each individual has a trait (attack or defence) that is explicitly modelled and the probability of the interaction to occur successfully increases with increased trait-matching. In addition, consumers can actively choose resources that guarantee greater fitness. We show that active consumer choice can generate coevolutionary units over time. It means that the traits of both consumers and resources converge into multiple groups with similar traits and the species interactions stay restricted to these groups over time. We also observed that network structure is more dependent on the parameter that delimits active consumer choice than on the intensity of selective pressure. Thus, our results support the idea that consumer active choice behaviour plays an important role in the ecological and evolutionary processes that structure interacting communities.