Data and code for: Past and future extinctions shape the body size - fruit size relationship between palms and mammalian frugivores

The dispersal of seeds by mammalian frugivores influences the structure
and composition of plant communities, but most ecosystems have undergone
defaunation over thousands of years, a process that continues today.
Understanding how past defaunation has affected fruit-frugivore
interactions will thus provide insights into how ecosystems may respond to
future frugivore loss. By integrating palm and mammalian frugivore trait
and occurrence data worldwide, we reveal a global positive relationship
between fruit size and body size of frugivore assemblages. Global
variation in fruit size is better explained by present-day frugivore
assemblages compared to those of the Late Pleistocene (including extinct
species), suggesting a substantial ecological and evolutionary
reorganization after Pleistocene mammal extinctions. Interestingly, the
reverse is true for the Neotropics where some large-fruited palm species
may have persisted over thousands of years following extinction of their
main seed dispersers. Simulations of frugivore extinction over the next
100 years suggest that changes in body size will require up to a 4%
assemblage-level decrease in palm fruit sizes to maintain the current
global frugivore body size - fruit size relationship. Absolute changes in
assemblage-level means of palm fruit size were on average up to two-fold
higher than observed species-level estimates of seed size change following
defaunation. Overall, our results suggest that while some large-fruited
palms may persist after the loss of their main dispersers, many palms may
be unable to keep pace with future defaunation through evolutionary
changes in fruit size alone. The burden of the impact of the extinction of
seed dispersers will probably be disproportionately borne by large-fruited
palms, possibly over thousands of years to come.