Contrasting effects of frugivore assemblages and phylogeny on global variation in fruit length and width

Nowadays, the evolution of fruit size is still poorly understood though theories of coevolution between fleshy fruits and frugivores have long pointed out the effects of different-sized frugivores and phylogeny. We compile a global-scale dataset on fruit traits of 312 fleshy-fruited plants and frugivore body size from over 300 interaction networks exposed to very different suites of frugivores, and reveal a global positive relationship between frugivore body size and fruit size, i.e., length and width. Using partial R2s model that accounts for species’ shared evolutionary histories, we first show that global variation in fruit width is explained by frugivorous assemblages rather than phylogeny and leaf area. Despite significant evolutionary correlation between fruit length and width, fruit length appears to be more phylogenetically constrained and less sensitive to frugivore-driven selection than width. Our large-scale study provides first evidence of strong phylogenetic constraints of fruit length and frugivore-driven selection on fruit width, providing a novel mechanistic explanation for better understanding the evolution of fruit size across fleshy-fruited plant species.