Functional Extinction of Birds Drives Rapid Evolutionary Changes in Seed Size

• Published in: Science (American Association for the Advancement of Science) Vol. 340; no. 6136; pp. 1086 - 1090
• Main Authors: Galetti, Mauro, Guevara, Roger, Côrtes, Marina C., Fadini, Rodrigo, Von Matter, Sandro, Leite, Abraão B., Labecca, Fábio, Ribeiro, Thiago, Carvalho, Carolina S., Collevatti, Rosane G., Pires, Mathias M., Guimarães, Paulo R., Brancalion, Pedro H., Ribeiro, Milton C., Jordano, Pedro
• Format: Journal Article
• Language: English
• Published: Washington, DC American Association for the Advancement of Science 31.05.2013; The American Association for the Advancement of Science
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Animals; Applied ecology; Arecaceae; Aves; Biological and medical sciences; Biological Evolution; Birds; Brazil; Climate change; Coalescence; Community composition; Conservation, protection and management of environment and wildlife; Cotingidae; data collection; Demecology; Ecological function; ecosystems; Environmental degradation: ecosystems survey and restoration; Evolution; Evolutionary biology; Extinct species; extinction; Extinction, Biological; Feeding Behavior; Forest regeneration; Forestry; Fruits; Fundamental and applied biological sciences. Psychology; General forest ecology; Generalities. Production, biomass. Quality of wood and forest products. General forest ecology; Germination; habitat fragmentation; Plant ecology; Plants and fungi; rain forests; Rainforests; Ramphastidae; Seed size; Seeds; Seeds - anatomy & histology; Seeds - physiology; Species; Species extinction; Trees; Tropical forests; Tropical rain forests; South America; Brazil; America; Biometrics; Monocotyledones; Seeds; Species extinction; Frugivorous; Tropical forest; Vegetation dynamics; Ecological damage; Vertebrata; Animal plant relation; Angiospermae; Atlantic Façade; Spermatophyta; Local scope; Key species; Palmae; Fruit tree; Aves; Environmental monitoring; Animal population
• ISSN: 0036-8075; 1095-9203; 1095-9203
• DOI: 10.1126/science.1233774

Local extinctions have cascading effects on ecosystem functions, yet little is known about the potential for the rapid evolutionary change of species in human-modified scenarios. We show that the functional extinction of large-gape seed dispersers in the Brazilian Atlantic forest is associated with the consistent reduction of the seed size of a keystone palm species. Among 22 palm populations, areas deprived of large avian frugivores for several decades present smaller seeds than nondefaunated forests, with negative consequences for palm regeneration. Coalescence and phenotypic selection models indicate that seed size reduction most likely occurred within the past 100 years, associated with human-driven fragmentation. The fast-paced defaunation of large vertebrates is most likely causing unprecedented changes in the evolutionary trajectories and community composition of tropical forests.