EEB Friday Seminar Series - Ant-fruit/seed interactions in Neotropical ecosystems: Effects on the biology of seeds and seedlings

Although most shrub and tree species in tropical environments are primarily vertebrate-dispersed, interactions between ants and fallen fleshy diaspores are frequent. Our studies have focused on the services provided by ants to fallen fleshy diaspores of primarily vertebrate-dispersed trees in Brazilian Cerrado savanna and Atlantic rainforest. In this talk, I report which ant species interact with fallen diaspores, their contribution to seed removal, and effects on seedling establishment and growth. Field studies by our group confirm the prevalence of interactions between ants and fallen fleshy diaspores, revealing potential ant-derived benefits to seeds and seedlings in both biomes. Although seed dispersal distances by ants are shorter compared to birds, our data show that fine-scale, ant-induced seed movements may ultimately enhance plant regeneration at early developmental stages in Cerrado and Atlantic rainforest. Current human-induced fragmentation and defaunation of tropical environments suggests that short-distance dispersal by ants may become increasingly important in the dynamics of ecosystems, since many vertebrate seed dispersers have been locally extirpated or are in decline.