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Abstract The patterns and drivers of pollen transport on insect bodies can have important consequences for plant reproductive success and floral evolution; however, they remain little studied. Recently, pollinator bodies have been further described as pollen competitive arenas, where pollen grains can compete for space, with implications for the evolution of pollen dispersal strategies and plant community assembly. However, the identity, strength, and diversity of pollen competitive interactions and how they vary across pollinator functional groups is not known. Evaluating patterns and drivers of the pollen co‐transport landscape and how these vary across different pollinator groups is central to further our understanding of floral evolution and co‐flowering community assembly.Here, we integrate information on the number and identity of pollen grains on individual insect pollen loads with network analyses to uncover novel pollen co‐transport networks and how these vary across pollinator functional groups (bees and bee flies). We further evaluate differences in pollen load size, species composition, diversity and phylogenetic diversity among insect groups and how these relate to body size and gender.Pollen co‐transport networks were diverse and highly modular in bees, with groups of pollen species interacting more often with each other on insect bodies. However, the number, identity and frequency of competitors that pollen grains encounter on insect bodies vary between some pollinator functional groups. Other aspects of pollen loads such as their size, richness and phylogenetical diversity were shaped by bee size or gender, with females carrying larger but less phylogenetically diverse pollen loads than males.Synthesis. Our results show that the number, identity and phylogenetic relatedness of pollen competitors changes as pollen grains travel on the body of different pollinators. As a result, pollinator groups impose vastly different interaction landscapes during pollen transport, with so far unknown consequences for plant reproductive success, floral evolution and community assembly. 

ABSTRACT Flowering plants can be visited by a wide diversity of pollinating insects; however, the structure of plant–insect interactions for non‐bee pollinators is not well‐known, even though non‐bee insects can play a central role in the pollination of many plant species. Pollination by non‐syrphid flies, such as bee flies (Bombylius majorL., Bombyliidae, Diptera), has often been underappreciated. Bee flies represent a diverse group of long‐tongue nectar‐feeding insects that are often reported as generalists who visit flowers indiscriminately. Here, we used individual‐based pollen transport networks to assess patterns of individual foraging in bee flies over two flowering seasons in a diverse co‐flowering community. Using this approach, we uncover the structure (e.g., modular vs. nested) of bee fly individual foraging and the degree of individual specialisation. We further evaluate the role of resource availability (floral abundance) and intraspecific trait variation (proboscis length and body size) in shaping individual specialisation. Overall, bee flies visited 20 different plant species. However, network analysis shows that individuals are more specialised and tend to partition the floral resource as reflected by the high degree of network modularity. Most bee fly individuals concentrate their foraging on only a few floral resources (two to four plant species) suggesting strong niche partitioning in this group of pollinators. This modular foraging pattern was not explained by differences in resource availability over the season. Proboscis length, however, was negatively related to the level of individual specialisation. Individuals with larger proboscis had larger foraging niches (less specialisation) perhaps due to easier access to a wide range of plant species with different floral tube sizes. Overall, our study reveals high individual specialisation and niche partitioning in bee‐fly interactions, mediated by differences in proboscis length, and with important implications for pollen transfer dynamics, plant–plant competition and plant reproductive success in diverse co‐flowering communities.