Inequalities in intraspecific plant–lemur interactions drive seed dispersal patterns

Biotic interactions occur between individuals and accumulate to shape species‐level interaction structure across a community. Skewed interaction structures, where a few individuals are highly connected and most have few interactions, are increasingly identified at the individual‐level. However, how individual‐level interactions accumulate to shape species‐level interaction outcomes remains unclear. We studied the interactions of three frugivorous lemur species ( Varecia variegata editorum , Eulemur rufifrons and Eulemur rubriventer ) with individual plants within a defined area of 4 km 2 . We examined the consistency of skewed patterns across time, lemur species, and plant species; compared individual‐ and species‐level network structure; investigated the intrinsic (DBH and fruit crop size) and extrinsic (fruit availability and richness) factors affecting interaction structure; and tested interaction structure impact on seed dispersal. We found a substantial and consistent skew in the interactions of individual plants with the lemurs, such that we observed a single visit for 70% of all plant individuals. This skewed pattern was consistent across time, lemur species, and plant species. Highly visited plant individuals (with > 20 visits per lemur species) occurred infrequently and only for visitation by V. variegata editorum and E. rubriventer. These differences in lemur visitation were significant at the individual level, and non‐significant at the species scale. Individual interaction networks were smaller, more specialized, and had lower connectivity than their species counterparts. These differences demonstrate the importance of individual‐level interactions, which contain substantial interaction variation not present at the species scale. Individual‐level interactions were positively influenced only by DBH, and fruit crop size across the study area. This skewed interaction structure impacted seed dispersal patterns, such that seeds were most likely to be deposited within 15 m of highly visited plants. Our results highlight the importance of individual‐level interaction variation for seed dispersal mutualisms and call for further study on the consistency of such patterns across ecosystems.