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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 Sensory organs must develop alongside the skull within which they are largely encased, and this relationship can manifest as the skull constraining the organs, organs constraining the skull, or organs constraining one another in relative size. How this interplay between sensory organs and the developing skull plays out during the evolution of sensory diversity; however, remains unknown. Here, we examine the developmental sequence of the cochlea, the organ responsible for hearing and echolocation, in species with distinct diet and echolocation types within the ecologically diverse bat super‐family Noctilionoidea. We found the size and shape of the cochlea largely correlates with skull size, with exceptions ofPteronotus parnellii, whose high duty cycle echolocation (nearly constant emission of sound pulses during their echolocation process allowing for detailed information gathering, also called constant frequency echolocation) corresponds to a larger cochlear and basal turn, andMonophyllus redmani, a small‐bodied nectarivorous bat, for which interactions with other sensory organs restrict cochlea size. Our findings support the existence of developmental constraints, suggesting that both developmental and anatomical factors may act synergistically during the development of sensory systems in noctilionoid bats. 

Abstract Although cases of independent adaptation to the same dietary niche have been documented in mammalian ecology, the molecular correlates of such shifts are seldom known. Here, we used genomewide analyses of molecular evolution to examine two lineages of bats that, from an insectivorous ancestor, have both independently evolved obligate frugivory: the Old World family Pteropodidae and the neotropical subfamily Stenodermatinae. New genome assemblies from two neotropical fruit bats (Artibeus jamaicensisandSturnira hondurensis) provide a framework for comparisons with Old World fruit bats. Comparative genomics of 10 bat species encompassing dietary diversity across the phylogeny revealed convergent molecular signatures of frugivory in both multigene family evolution and single‐copy genes. Evidence for convergent molecular adaptations associated with frugivorous diets includes the composition of three subfamilies of olfactory receptor genes, losses of three bitter taste receptor genes, losses of two digestive enzyme genes and convergent amino acid substitutions in several metabolic genes. By identifying suites of adaptations associated with the convergent evolution of frugivory, our analyses both reveal the extent of molecular mechanisms under selection in dietary shifts and will facilitate future studies of molecular ecology in mammals.