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Kaliszewska, Z. A.

Publications and source records attributed to Kaliszewska, Z. A..

3 recordsLinked to original sources

Testing for reciprocal trait influence in plant-frugivore interactions using generalized joint attribute modeling

Under an adaptive hypothesis, the reciprocal influence between mutualistic plants and frugivores is expected to result in dispersal syndromes comprising both frugivore and plant traits that structure fruit consumption. Tests of this adaptive hypothesis, however, focus on traits of either fruits or frugivores but not both and often ignore within-species variation. To overcome these limitations, we analyze traits for the mutualistic ecological network comprising Carollia bats that feed on and disperse Piper seeds. For these analyses, we use generalized joint attribute modeling (GJAM), a Bayesian modeling approach that simultaneously accounts for multiple sources of variance across trait types. In support of the adaptive hypothesis and indicating niche partitioning among Carollia bats, we find differential consumption of a suite of Piper species influenced by bat traits such as body size; however, Piper morphological traits had no effect on bat consumption. Slow evolutionary rates, dispersal by other vertebrates, and unexamined fruit traits, such as Piper chemical bouquets, may explain the lack of association between bat Piper consumption 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.

ecology↗

Diversity in olfactory receptor repertoires is associated with dietary specialization in a genus of frugivorous bat

Mammalian olfactory receptors (ORs) are a diverse family of genes encoding proteins that directly interact with environmental chemical cues. ORs evolve via gene duplication in a birth-death fashion, neofunctionalizing and pseudogenizing over time. Olfaction is a primary sense used for food detection in plant-visiting bats, but the relationship between dietary specialization and OR repertoires is unclear. Within neotropical Leaf-nosed bats (Phyllostomidae), many lineages are plant specialists, and some have a distinct OR repertoire compared to insectivorous species. Yet, whether specialization on particular plant genera is associated with the evolution of more specialized OR repertoires has never been tested. Using targeted sequence capture, we sequenced the OR repertoires of three sympatric species of short-tailed leaf-nosed bats (Carollia), which vary in their degree of specialization on the fruits of Piper plants. We characterized orthologous versus duplicated receptors among Carollia species, and identified orthologous receptors and associated paralogs to explore the diversity and redundancy of the receptor gene repertoire. The most dedicated Piper specialist, Carollia castanea, had lower OR diversity compared to the two more generalist species (sowelli, perspicillata), but we discovered a few unique sets of ORs within C. castanea with exceptional redundancy of similar gene duplicates. These unique receptors potentially enable C. castanea to detect Piper fruit odorants to an extent that the other species cannot. C. perspicillata, the species with the most generalist diet, had a larger diversity of functional receptors, suggesting the ability to detect a wider range of odorant molecules. The variation among ORs may be a factor in the coexistence of these sympatric species, facilitating the exploitation of different plant resources. Our study sheds light on how gene duplication plays a role in dietary adaptations and underlies patterns of ecological interactions between bats and plants. Impact Statement--though it asks for 3-4 sentencesThe sense of smell is essential to how many animals detect food, yet few studies have demonstrated how dietary evolution has shaped olfactory receptor genes, which encode proteins that bind to environmental scent cues, including food odorants. We compared the evolutionary history of olfactory receptor repertoires in three co-occurring neotropical bat species along a spectrum of dietary specialization on the fruits of Piper plants. We found the more generalist species possessed a more diverse olfactory receptor profile, potentially reflecting an ability to detect more diverse arrays of fruit scent compounds, while the specialist had a narrower profile that demonstrated more redundancy. By introducing creative approaches to measure diversity in large gene families and connecting diet specialization and molecular diversity, this study makes an unprecedented contribution to evolutionary biology.

evolutionary biology↗

A fruitful endeavor: scent cues and echolocation behavior used by Carollia castanea to find fruit

Frugivores have evolved sensory and behavioral adaptations that allow them to find ripe fruit effectively, but the relative importance of different senses in varying foraging scenarios is poorly known. Within Neotropical ecosystems, short-tailed fruit bats (Carollia: Phyllostomidae) are abundant nocturnal frugivores, relying primarily on plants of the genus Piper as a food resource. Previous research has demonstrated Carollia employ olfaction and echolocation to locate Piper fruit, but it is unknown how their sensory use and foraging decisions are influenced by the complex diversity of chemical cues that fruiting plants produce. Using wild C. castanea and their preferred food, Piper scintillans, we conducted behavioral experiments to test two main hypotheses: (1) foraging decisions in C. castanea are primarily driven by ripe fruit scent and secondarily by vegetation scent, and (2) C. castanea re-weight their sensory inputs to account for available environmental cues, such that bats rely more heavily on echolocation in the absence of adequate scent cues. Our results suggest that C. castanea requires olfactory information and relies almost exclusively on ripe fruit scent to make foraging attempts. Ripe fruit scent is chemically distinct from vegetation scent in P. scintillans, with a greater abundance of {beta}-caryophyllene, germacrene D and {beta}-elemene, and a few unique compounds. Although variation in echolocation call parameters was independent of scent cue presence, bats emitted longer and more frequent echolocation calls in trials where no fruit scent was present. Altogether, these results highlight the adaptations, plasticity, and potential constraints in the sensory system of neotropical fruit bats. SIGNIFICANCE STATEMENTLittle is known about the relative importance of different senses and which plant cues are most important for fruit location by frugivores. We conducted behavioral experiments on short-tailed fruit bats (Carollia castanea), which use a combination of olfaction and echolocation to find ripe fruit, and their preferred food source (Piper scintillans) to test (1) which plant scent cues drive food selection and (2) if bats alter their echolocation behaviors based on which scent cues are present. We find that C. castanea rely almost exclusively on ripe fruit scent to forage, and echolocate more frequently when fruit scent is absent. Ripe fruit scent is chemically different from vegetation scent in P. scintillans, potentially providing a clear signal of food availability to mutualistic bats. These results highlight the sensory adaptations and behavioral flexibility of fruit bats as they navigate the cues provided by fruiting plants.

ecology↗