Biology subjects

Nevo, O.

Publications and source records attributed to Nevo, O..

4 recordsLinked to original sources

bioRxiv2026

Pervasive ethanol in the fruits and floral nectars consumed by tropical frugivores

Dietary ethanol has long been proposed as a selective force shaping the diets and physiology of tropical frugivores and nectarivores, yet this idea has rested on measurements from only a few species and sites. Here, we present the first global survey of ethanol in wild fruits and flowers (591 and 37 species, respectively, across 18 countries) and test ecological and phylogenetic predictors of its variation. We detected ethanol in the ripened fruits of 72% of angiosperm species (211 species, N [≥] 3 per species; 0.021% - 3.9% alcohol by volume (ABV)). Ethanol was also detected in the flowers of 12 species (0.037% - 0.73% ABV). Maximum fruit ethanol varied with temperature, humidity, and phylogenetic relatedness, and it was higher in ripe fruits collected from the forest floor relative to their canopy counterparts. We then extrapolated potential daily ethanol consumption for 10 primate species. Estimated maximum daily ethanol ingestion for primates ranged from negligible to 0.72 g/kg/day on average (equivalent to 5.1 international standard drinks, 10 g ethanol each, for a 70 kg human). Our findings show that ethanol is widespread in plant reproductive tissues and shaped by both phylogeny and environment, supporting the hypothesis that dietary ethanol has been a pervasive selective pressure on fruit- and nectar-feeding animals.

ecology↗

bioRxiv2026

Metrics matter: Modelling plant-frugivore networks in a tropical dry forest ecosystem

Arboreal camera trapping is an emerging remote sensing tool for building plant-frugivore interaction networks with enormous potential to provide new insights into seed dispersal as an eco-evolutionary process. Interaction data derived from camera trap videos broadly falls into two categories: visitation, indicating the presence of an animal in a tree, and intake, indicating true fruit consumption. These linked approximations of seed dispersal may or may not provide distinct sets of information, shaping our understanding of network dynamics, yet the extent to which emergent network structure depends on variable choice is unknown. To address this gap, we deployed camera traps in the canopy of 21 plant species in the Costa Rican tropical dry forest, an endangered biome with sparse community-wide plant-frugivore interaction data. Our objectives were: 1) Quantify plant-frugivore network structure in the tropical dry forest via network, group, and species-level metrics; and 2) Compare metrics between visitation and intake networks. We find strong structural patterns of low connectance, low nestedness, high modularity, and low niche overlap that differ significantly from null expectations in the same direction in both networks. The visitation network exhibited significantly greater modularity & species degree than the intake network, while the intake network exhibited significantly greater plant niche overlap than the visitation network. These findings suggest that the likelihood of consuming fruit on camera differs across species, which may have downstream consequences on other emerging metric estimations. Researchers seeking to build quantitative plant-frugivore networks should therefore consider visitation and intake variables in concert when relying on camera trap data. This work provides foundational plant-frugivore interaction data for a critically endangered biome and enhances our understanding of camera trapping as a remote sensing tool in frugivory and seed dispersal research.

ecology↗

bioRxiv2026

Fruit scent chemistry: adaptation to seed dispersal interactions

Fleshy fruits have evolved diverse traits to attract seed dispersers in response to frugivore behavior and sensory capacities. Fruit scent has been suggested to signal ripeness and nutritional quality, yet the volatile components involved and the information they convey remain poorly understood. It is unknown which information is encoded in fruit scent, whether plants actively synthesize these signals, and thus whether scent constitutes an evolved communication system shaping seed-dispersal interactions. Aliphatic esters, chemicals whose odor is often described as fruity, are abundant in some ripe fruits, especially those dispersed by animals which tend to rely on their sense of smell for fruit selection. Moreover, they have been argued to be associated with sugar content, potentially rendering them an honest signal and hence a hotspot of animal-plant chemical communication. We investigated whether aliphatic esters indicate fruit quality honestly and represent an adaptive trait shaped by disperser identity. Using 13 fig species (Ficus spp.; Moraceae) in Madagascar, we quantified seed dispersal by multiple animals using a quantitative ecological network. We then quantified chemical signals and nutritional rewards using thermal desorption gas chromatography-mass spectrometry (TD-GCMS) and high-performance liquid chromatography (HPLC), and used genome-guided transcriptome assembly to identify the candidate genes responsible for ester signaling. Our results show that (a) aliphatic esters occur more frequently in species dispersed primarily by olfactory-oriented mammals than in those dispersed by visually oriented birds; (b) ester abundance correlates positively with soluble sugar across species only in mammal-dispersed species, indicating an honest signal that is activated only when ecologically relevant; and (c) putative AAT gene revealing elevated expression associated with the increased abundance of aliphatic esters, sugars in single mammal-dispersed taxon. Together, these findings support the hypothesis that fruits have evolved to utilize the biochemical link between esters (signals) and sugars (rewards) to provide honest signals to seed dispersers.

plant biology↗

bioRxiv2026

Effects of temperature gradient on flower and fruit traits: a meta analysis

Pollination and seed dispersal by animals are key drivers of terrestrial biodiversity and ecosystem functioning. Effective mutualistic interactions rely heavily on temporal and functional- trait matching between plants and animals. While global warming is known to induce shifts in plant traits, the extent and direction in which higher temperatures may systematically alter flower and fruit traits across species in natural habitats remains poorly understood. Using elevation as a proxy for temperature across natural populations, we conducted a meta-analysis evaluating 21 quantitative functional traits (15 floral, 6 fruit) across 82 studies and 161 species. Standardized mixed-effects linear regression models revealed widespread, systemic responses to elevational temperature gradients in both reproductive structures. In flowers, higher temperatures were systematically associated with changes in petal and sepal width and length (and hence morphology), longevity, nectar volume, number of flowers, and inflorescence length. In fruits, elevation was associated with changes in vitamin C content, crop size, weight and width. Taken together, these results demonstrate that warming temperatures exert widespread, multi-axis effects on the morphology, availability, timing, and nutritional quality of both flowers and fleshy fruits. Given that flower and fruit traits are developmentally linked and co-determine animal visitor dynamics, these temperature-driven phenotypic shifts are likely to propagate cascading disruptions throughout plant-pollinator and plant-frugivore interaction networks under continued climate change.

ecology↗