Summary: Ecology, 89(5), 2008, pp. 1364­1374
Ó 2008 by the Ecological Society of America
DENSITY-MEDIATED, CONTEXT-DEPENDENT CONSUMER­RESOURCE
INTERACTIONS BETWEEN ANTS AND EXTRAFLORAL NECTAR PLANTS
SCOTT A. CHAMBERLAIN
1
AND J. NATHANIEL HOLLAND
Department of Ecology and Evolutionary Biology, Rice University, 6100 South Main Street, Houston, Texas 77005 USA
Abstract. Interspecific interactions are often mediated by the interplay between resource
supply and consumer density. The supply of a resource and a consumer's density response to it
may in turn yield context-dependent use of other resources. Such consumer­resource
interactions occur not only for predator­prey and competitive interactions, but for mutualistic
ones as well. For example, consumer­resource interactions between ants and extrafloral nectar
(EFN) plants are often mutualistic, as EFN resources attract and reward ants which protect
plants from herbivory. Yet, ants also commonly exploit floral resources, leading to
antagonistic consumer­resource interactions by disrupting pollination and plant reproduction.
EFN resources associated with mutualistic ant­plant interactions may also mediate
antagonistic ant­flower interactions through the aggregative density response of ants on
plants, which could either exacerbate ant­flower interactions or alternatively satiate and
distract ants from floral resources. In this study, we examined how EFN resources mediate the

Source: Azevedo, Ricardo - Department of Biology and Biochemistry, University of Houston
Holland, J. Nathaniel - Department of Ecology and Evolutionary Biology, Rice University

Collections: Biology and Medicine; Environmental Sciences and Ecology