Results/Conclusions: We find that morphological traits and toxicity vary widely among species, between immature and mature stages, and within fruit. At the mature (immature) stage, species range in mean diaspore size from 0.9 (0.4) mg to 2196 (185.1) mg. In the large-seeded species, the ratio of physical protection to seed reserve shifts from 5.1 in immature fruits to .59 in mature fruits. In the small-seeded species, the ratio at maturity is 1.8, whereas the seed is undeveloped at the immature stage. Trait data for immature fruits help explain patterns of seed survival among species in response to natural enemy removal treatments. Removal treatments increased germination of larger-seeded species, while having no effect on small-seeded species. Identification of consistent relationships between relatively easily measured fruit traits and the impacts of different natural enemies would greatly facilitate generalization to unstudied species and help identify those species at greatest risk under environmental change. Incorporating plant traits that reflect ecological mechanisms with experimental results aids in generalizing process from pattern and enables prediction. This is particularly important in tropical forests, where high species diversity makes it logistically impossible to study every plant life history stage of every species.