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Abstract The ecological interaction between fleshy fruits and frugivores is influenced by diverse mixtures of secondary metabolites that naturally occur in the fruit pulp. Although some fruit secondary metabolites have a primary role in defending the pulp against antagonistic frugivores, these metabolites also potentially affect mutualistic interactions. The physiological impact of these secondary metabolites on mutualistic frugivores remains largely unexplored. Using a mutualistic fruit bat (Carollia perspicillata), we showed that ingesting four secondary metabolites commonly found in plant tissues affects bat foraging behavior and induces changes in the fecal metabolome. Our behavioral trials showed that the metabolites tested typically deter bats. Our metabolomic surveys suggest that secondary metabolites alter, either by increasing or decreasing, the absorption of essential macronutrients. These behavioral and physiological effects vary based on the specific identity and concentration of the metabolite tested. Our results also suggest that a portion of the secondary metabolites consumed is excreted by the bat intact or slightly modified. By identifying key shifts in the fecal metabolome of a mutualistic frugivore caused by secondary metabolite consumption, this study improves our understanding of the effects of fruit chemistry on frugivore physiology. 

ABSTRACT Tropical deforestation is occurring at alarming rates, creating an urgent need for global prioritization of restoration efforts. One potential forest recovery strategy is to boost seed‐dispersing animal activity (e.g., fruit‐eating bats) to increase seed availability in degraded areas. In this study, we investigated the efficacy of synthetic chemical lures in attracting fruit bats and enhancing seed rain in northeastern Costa Rica. The chemical lures were composed of a few volatile organic compounds commonly found in ripe bat‐dispersed fruits. Daily deployment of the chemical lures resulted in a significant increase in the capture ofCarolliaspp., a key neotropical seed disperser, but no detectable effect on other fruit bats. The 15‐day deployment of chemical lures also increased the average of total seeds collected in seed traps. However, the effect of lures explained only a small portion of the total variance in seed rain, highlighting the potential context‐dependency of these results. Still, in contrast to the previously studied essential oil‐based lures, synthetic lures hold the potential to be applied across a broader spectrum of restoration initiatives due to simplified manufacturing and improved reproducibility. Although additional research is essential to understand the full potential for use in restoration efforts, our study demonstrates the effectiveness of synthetic chemical lures in attracting fruit bats and potentially augmenting seed rain. 

ABSTRACT Under an adaptive hypothesis, the reciprocal influence between mutualistic plants and frugivores is expected to result in suites of matching frugivore and plant traits that structure fruit consumption. Recent work has suggested fruit traits can represent adaptations to broad groups of functionally similar frugivores, but the role of frugivore traits and within‐species variation in structuring fruit consumption is less understood. To address these knowledge gaps, we assess the presence of reciprocal trait matching for the mutualistic ecological network comprising ofCarolliabats that feed on and dispersePiperseeds. We used generalized joint attribute modeling (GJAM), a Bayesian modeling approach that simultaneously accounts for multiple sources of variance across trait types. In support of frugivore adaptation to their dietary composition and suggesting niche partitioning amongCarolliabats, we find differential consumption of a suite ofPiperspecies influenced by bat traits such as body size; however, thePipermorphological traits considered had no effect on bat consumption. Slow evolutionary rates, dispersal by other vertebrates, and unexamined fruit traits, such asPiperchemical bouquets, may explain the lack of association between batPiperconsumption and fruit morphological traits. We have identified a potential asymmetric influence of frugivore traits on plant–frugivore interactions, providing a template for future trait analyses of plant–animal networks. As intraspecific trait variation is rarely included in studies on trait matching, this paper contributes to closing that important knowledge gap. 

Abstract The production of complex mixtures of secondary metabolites is a ubiquitous feature of plants. Several evolutionary hypotheses seek to explain how phytochemical diversity is maintained, including the synergy hypothesis, the interaction diversity hypothesis, and the screening hypothesis. We experimentally tested a set of predictions derived from these hypotheses by manipulating the richness and structural diversity of phenolic metabolites in the diets of eight plant consumers. Across 3940 total bioassays, there was clear support for the interaction diversity hypothesis over the synergy or screening hypotheses. The number of consumers affected by a particular phenolic composition increased with increasing richness and structural diversity of compounds. Furthermore, the bioactivity of phenolics was consumer‐specific. All compounds tested reduced the performance of at least one consumer, but no compounds affected all consumers. These results show how phytochemical diversity may be maintained in nature by a complex selective landscape exerted by diverse communities of plant consumers.