Data from: Fruit-quality tradeoffs generate asymmetry in plant reliance on mutualistic frugivores

Seed dispersal is a fundamental ecological process influencing the
evolution of plant life-history strategies. In fleshy-fruited plants
dispersed by mutualistic frugivores, variation in fruit traits among
closely related species may shape the temporal and spatial dynamics of
dispersal events critical to population success. Here, we test a tradeoff
model for dispersal strategies, inspired by Grime’s triangle of
life-history tradeoffs, that links fruit quality and seed traits (e.g.,
nutrients, chemical defenses, seed dormancy) to plant reliance on
frugivore-mediated dispersal. The model predicts that species producing
nutrient-rich, rewarding fruits benefit from frequent frugivory
interactions, leading to enhanced seed deposition and seedling recruitment
across broader spatial and temporal scales. Conversely, species investing
in chemically defended fruits or seed dormancy are expected to rely less
on frugivores and more on vegetative reproduction or persistent seed
banks. We experimentally evaluated this model using three Solanum species
(Solanaceae) with distinct fruit traits and seed dormancy levels. For each
species, we documented frugivory interactions and conducted a
seed-addition experiment in the field mimicking frugivore dispersal to
assess how the spatial and temporal patterns of seed deposition by
frugivores affect seedling emergence. Our results show that the Solanum
species with sugar-rich fruits experienced higher frugivory rates and
greater seedling emergence under seed-addition treatments mimicking
frugivore dispersal. In contrast, species investing more in pulp defenses
or seed dormancy engaged in fewer frugivory interactions and had lower
seedling emergence in seed addition treatments mimicking dispersal by
frugivores. Altogether, our findings show that differences in fruit traits
and quality can mediate tradeoffs among dispersal strategies, leading to
interspecific variation in how strongly plant species may rely on
frugivory mutualisms for recruitment.