Evolution of Fish Frugivory and Seed Dispersal
Frugivory is a widespread feeding habit among tropical freshwater fishes, yet very few people know about this unique plant-animal interaction. In three synthesis articles (Correa et al. 2007, Bioscience; Horn & Correa et al. 2011, Acta Oecologica; and Correa et al. 2015a, Biological Reviews), we demonstrated that fish frugivory involves nearly 300 species of tropical and temperate fish and, just in the Neotropics, over 500 plant species. Among fishes, frugivory evolved independently in families of Neotropical and African Characiforms, and within Neotropical serrasalmids (i.e., Pacus and Piranhas), frugivory likely originated from an omnivore ancestor. Most importantly, fish evolved well before most other groups of vertebrate frugivores in South America, around 70 million years ago. This is a surprising finding that suggests that fish likely were the first seed dispensers in the New World and played important roles in structuring wetland plant communities and riparian forests.
Our work also demonstrated that fruit characteristics, such as having a fleshy pulp, facilitated the establishment of interactions between fish and fruits and the fish’s role as seed dispersers, known as ichthyochory.
Current research investigates whether fruit characteristics, including nutrient composition, influence the likelihood of seeds surviving fish consumption. Another line of research is investigating how characteristics of floodplain forests influence patterns of species distribution and richness of fruit-eating fishes in Amazonia.
Collaborators: Pablo Tedesco (University Paul Sabatier, France), Hernan Lopez-Fernandez and Matthew Kolmann (University of Michigan), Jill Anderson (University of Georgia), Jerry Pehna, Catia Nunes da Cunha, and Joisiane Araujo (Federal University of Mato Grosso, Brazil).