Network analysis is a powerful tool to understand community‐level plant–pollinator interactions. We evaluated the role of floral visitors on plant fitness through a series of pollination exclusion experiments to test the effectiveness of pollinators of an Ipomoea community in the Pacific coast of Mexico, including: (1) all flower visitors, (2) visitors that contact the reproductive organs, (3) visitors that deposit pollen on stigmas, and (4) visitors that mediate fruit and seed production. Our results show that networks built from effective pollination interactions are smaller, less connected, more specialized and modular than floral visitor networks. Modules are associated with pollinator functional groups and they provide strong support for pollination syndromes only when non‐effective interactions are excluded. In contrast to other studies, the analyzed networks are not nested. Our results also show that only 59% of floral visitors were legitimate pollinators that contribute to seed production. Furthermore, only 27% of the links in visitation network resulted in seed production. Our study shows that plant‐pollination networks that consider effectiveness measures of pollination in addition to floral visitation provide insightful information about the different role floral visitors play in a community, encompassing a large number of commensalistic/antagonistic interactions and the more restricted set of mutualistic relationships that underlie the evolution of convergent floral phenotypes in plants.

Plant‐pollinator interactions are fundamental to ecosystem functioning; however, the role that succession and phenology have on these interactions is poorly understood, particularly in endangered tropical ecosystems. In highly diverse ecosystems such as tropical dry forests (TDF), variation in water and food availability determines the life cycles of animal pollinators. Therefore, understanding patterns of flowering phenology and plant‐pollinator interactions across seasons in successional environments is key to maintaining and restoring TDF. We analysed the functional dynamics of plant‐floral visitor interactions at the community level across a successional gradient in a Mexican TDF. We evaluated changes in the diversity of blooming plant species and floral visitors, phenological patterns, interaction network metrics and beta diversity among early, intermediate and late successional stages, between dry and rainy seasons. We found a higher diversity of blooming plant species and a higher richness of animal species in the intermediate and late successional stages. Peak abundance of floral visitors overlapped with flowering peaks in the late successional stages, but this was not consistently the case in the early and intermediate stages. Plant‐floral visitors networks differed in structure according to successional stage and season, but specialisation metrics were higher in late successional stages. Interaction networks were more dissimilar between dry and rainy seasons within successional stages than within seasons between successional stages, suggesting connectivity across successional sites during each season. In addition, closely related plant species do not share the same pollination systems in any successional stage. Synthesis. Our results showed that plant‐floral visitor interactions are dynamic and vary with flowering phenology and with successional changes in plant and animal diversity. Plant‐floral visitor interactions were more diverse and specialised in the late successional stages. In the rainy season, differences in network structure among successional stages are due to interaction rewiring, while in the dry season, it is caused by species turnover. Our results demonstrate that seasonality plays a key role in community diversity and network structure and highlight the importance of conserving mature forests to ensure the maintenance of critical pollination interactions across all successional stages.

Premise: Domestication of plant species results in phenotypic modifications and changes in biotic interactions. Most studies have compared antagonistic plantherbivore interactions of domesticated plants and their wild relatives, but little attention has been given to how domestication influences plant-pollinator interactions. Floral attributes and interactions of floral visitors were compared between sister taxa of the genus Cucurbita (Cucurbitaceae), the domesticated C. moschata, C. argyrosperma ssp. argyrosperma and its wild progenitor C. argyrosperma ssp. sororia in the place of origin. Methods: We conducted univariate and multivariate analyses to compare floral morphological traits and analyzed floral reward (nectar and pollen) quantity and quality between flowers of wild and domesticated Cucurbita taxa. Staminate and pistillate flowers of all three taxa were video recorded, and visitation and behavior of floral visitors were registered and analyzed. Results: Most floral morphological characteristics of flowers of domesticated taxa were larger in both staminate and pistillate flowers. Staminate and pistillate flowers presented distinct correlations between floral traits and integration indices between domesticated and wild species. Additionally, pollen quantity and protein to lipid ratio were greater in domesticated species. Cucurbit pollen specialists, Eucera spp., had the highest probability of visit for all Cucurbita taxa. Conclusions: We provide evidence that floral traits of domesticated and wild Cucurbita species experienced different selection pressures. Domesticated Cucurbita species may have more resources invested towards floral traits, thereby increasing attractiveness to pollinators and potentially plant reproductive success. Wild ancestor plant populations should be conserved in their centers of origin to preserve plantpollinator interactions.

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