Insights into the structure of plant-insect communities: Specialism and generalism in a regional set of non-pollinating fig wasp communities

Author(s)

Farache, F. H. A. ; Cruaud, A. ; Rasplus, J-Y ; Cerezini, M. T. ; Rattis, L. ; Kjellberg, F. ; Pereira, R. A. S.

• Document type: Journal article
• Source: ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY; v. 90, p. 11-pg., 2018-07-01.

Abstract

Insects show a multitude of symbiotic interactions that may vary in degree of specialization and structure. Gallinducing insects and their parasitoids are thought to be relatively specialized organisms, but despite their ecological importance, the organization and structure of the interactions they establish with their hosts has seldom been investigated in tropical communities. Non-pollinating fig wasps (NPFW) are particularly interesting organisms for the study of ecological networks because most species strictly develop their offspring within fig inflorescences, and show a multitude of life history strategies. They can be gall-makers, cleptoparasites or parasitoids of pollinating or of other non-pollinating fig wasps. Here we analysed a set of non-pollinating fig wasp communities associated with six species of Ficus section Americanae over a wide area. This allowed us to investigate patterns of specialization in a diverse community composed of monophagous and polyphagous species. We observed that most NPFW species were cleptoparasites and parasitoids, colonizing figs several days after oviposition by pollinators. Most species that occurred in more than one host were much more abundant in a single preferential host, suggesting specialization. The food web established between wasps and figs shows structural properties that are typical of specific antagonistic relationships, especially of endophagous insect networks. Two species that occurred in all available hosts were highly abundant in the network, suggesting that in some cases generalized species can be more competitive than strict specialists. The Neotropical and, to a lesser extent, Afrotropical NPFW communities seem to be more generalized than other NPFW communities. However, evidence of host sharing in the Old World is quite limited, since most studies have focused on particular taxonomic groups (genera) of wasps instead of sampling the whole NPFW community. Moreover, the lack of quantitative information in previous studies prevents us from detecting patterns of host preferences in polyphagous species. (AU)

• FAPESP's process: 15/06430-2 - Taxonomy, molecular phylogenetics, and evolution of host specialization in two genera of Neotropical fig wasps (Pegoscapus Cameron, 1906 and Idarnes Walker, 1843; Hymenoptera, Agaonidae).
• Grantee: Fernando Henrique Antoniolli Farache
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 08/03272-3 - Effects of forest fragmentation on the fig-fig wasp mutualism in the São Paulo State
• Grantee: Monise Terra Cerezini
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 04/10299-4 - Effects of the forest fragmentation in the State of São Paulo and other regions of the South and Southeast of the country in the functioning of populations of fig trees and in the fig-wasp mutualism of figs
• Grantee: Rodrigo Augusto Santinelo Pereira
• Support Opportunities: BIOTA-FAPESP Program - Young Investigators Grants
• FAPESP's process: 11/21485-7 - Chemistry ecology and community of wasps associated with fig trees
• Grantee: Rodrigo Augusto Santinelo Pereira
• Support Opportunities: Research Grants - Visiting Researcher Grant - International
• FAPESP's process: 07/06054-4 - Diversity of wasps (Hymenoptera: Chalcidoidea) associated with the genus Ficus (Moraceae) in São Paulo State
• Grantee: Fernando Henrique Antoniolli Farache
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 15/25417-7 - Diversity and evolution of host-species relationship of wasps associated with neotropical fig trees
• Grantee: Rodrigo Augusto Santinelo Pereira
• Support Opportunities: Regular Research Grants