Ant foraging on foliage can substantially affect how phytophagous insects use host plants and represents a high predation risk for caterpillars, which are important folivores. Ant-plant-herbivore interactions are especially pervasive in cerrado savanna due to continuous ant visitation to liquid food sources on foliage (extrafloral nectaries, insect honeydew). While searching for liquid rewards on plants, aggressive ants frequently attack or kill insect herbivores, decreasing their numbers. Because ants vary in diet and aggressiveness, their effect on herbivores also varies. Additionally, the differential occurrence of ant attractants (plant and insect exudates) on foliage produces variable levels of ant foraging within local floras and among localities. Here, we investigate how variation of ant communities and of traits among host plant species (presence or absence of ant attractants) can change the effect of carnivores (predatory ants) on herbivore communities (caterpillars) in a cerrado savanna landscape. We sampled caterpillars and foliage-foraging ants in four cerrado localities (70-460 km apart). We found that: (i) caterpillar infestation was negatively related with ant visitation to plants; (ii) this relationship depended on local ant abundance and species composition, and on local preference by ants for plants with liquid attractants; (iii) this was not related to local plant richness or plant size; (iv) the relationship between the presence of ant attractants and caterpillar abundance varied among sites from negative to neutral; and (v) caterpillars feeding on plants with ant attractants are more resistant to ant predation than those feeding on plants lacking attractants. Liquid food on foliage mediates host plant quality for lepidopterans by promoting generalized ant-caterpillar antagonism. Our study in cerrado shows that the negative effects of generalist predatory ants on herbivores are detectable at a community level, affecting patterns of abundance and host plant use by lepidopterans. The magnitude of ant-induced effects on caterpillar occurrence across the cerrado landscape may depend on how ants use plants locally and how they respond to liquid food on plants at different habitats. This study enhances the relevance of plant-ant and ant-herbivore interactions in cerrado and highlights the importance of a tritrophic perspective in this ant-rich environment. Ants are major predators of insect herbivores in tropical habitats. In the Brazilian savanna, negative effects by predatory ants on herbivores (caterpillars) are detectable at the community level, affecting patterns of host plant use by lepidopteran communities. The study highlights the importance of a tritrophic perspective in this ant-rich environment.842442452Anderson, M.J., A new method for non-parametric multivariate analysis of variance (2001) Austral Ecology, 26, pp. 32-46Barton, A.M., Spatial variation in the effect of ants on an extrafloral nectary plant (1986) Ecology, 67, pp. 495-504Bernays, E.A., Evolution of feeding behavior in insect herbivores: success seen as different ways to eat without being eaten (1998) BioScience, 48, pp. 35-44Blüthgen, N., Gebauer, G., Fiedler, K., Disentangling a rainforest food web using stable isotopes: dietary diversity in a species-rich ant community (2003) Oecologia, 137, pp. 426-435Bolker, B.M., Brooks, M.E., Clark, C.J., Geange, S.W., Poulsen, J.R., Stevens, M.H.H., Generalized linear mixed models: a practical guide for ecology and evolution (2009) Trends in Ecology and Evolution, 24, pp. 127-135Bronstein, J.L., Our current understanding of mutualism (1994) Quarterly Review of Biology, 69, pp. 31-51Bronstein, J.L., The contribution of ant-plant protection studies to our understanding of mutualism (1998) Biotropica, 30, pp. 150-161Brown, K.S., Gifford, D.R., Lepidoptera in the cerrado landscape and the conservation of vegetation, soil, and topographical mosaics (2002) The Cerrados of Brazil, pp. 201-222. , eds P.S. Oliveira & R.J. Marquis) -. Columbia University Press, New YorkByk, J., Del-Claro, K., Nectar- and pollen-gathering Cephalotes ants provide no protection against herbivory: a new manipulative experiment to test ant protective capabilities (2010) Acta Ethologica, 13, pp. 33-38Chamberlain, S.A., Holland, J.N., Density-mediated, context-dependent consumer-resource interactions between ants and extrafloral nectar plants (2008) Ecology, 89, pp. 1364-1374Davidson, D.W., Cook, S.C., Snelling, R.R., Chua, T.H., Explaining the abundance of ants in lowland tropical rainforest canopies (2003) Science, 300, pp. 969-972Del-Claro, K., Oliveira, P.S., Ant-Homoptera interactions in a neotropical savanna: the honeydew-producing treehopper, Guayaquila xiphias (Membracidae), and its associated ant fauna on Didymopanax vinosum (Araliaceae) (1999) Biotropica, 31, pp. 135-144De-Silva, D.L., Vásquez, A.S., Mallet, J., Selection for enemy-free space: eggs placed away from the host plant increase survival of a neotropical ithomiine butterfly (2011) Ecological Entomology, 36, pp. 667-672Díaz-Castelazo, C., Rico-Gray, V., Oliveira, P.S., Cuautle, M., Extrafloral nectary-mediated ant-plant interactions in the coastal vegetation of Veracruz, Mexico: richness, occurrence, seasonality and ant foraging patterns (2004) Ecoscience, 11, pp. 472-481Diniz, I., Morais, H.C., Lepidopteran caterpillar fauna of cerrado host plants (1997) Biodiversity and Conservation, 6, pp. 817-836Diniz, I., Braga, L., Lepesqueur, C., Silva, N., Morais, H., (2013) Lagartas do Cerrado - Guia de Campo, , Technical Books, Rio de JaneiroDutra, H.P., Freitas, A.V.L., Oliveira, P.S., Dual ant attraction in the neotropical shrub Urera baccifera (Urticaceae): the role of ant visitation to pearl bodies and fruits in herbivore deterrence and leaf longevity (2006) Functional Ecology, 20, pp. 252-260Dyer, L.A., Effectiveness of caterpillar defenses against three species of invertebrate predators (1997) Journal of Research on Lepidoptera, 34, pp. 48-68Floren, A., Biun, A., Linsenmair, K.E., Arboreal ants as key predators in tropical lowland rainforest trees (2002) Oecologia, 131, pp. 137-144Freitas, A.V.L., Oliveira, P.S., Biology and behavior of Eunica bechina (Lepidoptera: Nymphalidae) with special reference to larval defense against ant predation (1992) Journal of Research on Lepidoptera, 31, pp. 1-11Freitas, A.V.L., Oliveira, P.S., Ants as selective agents on herbivore biology: effects on the behaviour of a non-myrmecophilous butterfly (1996) Journal of Animal Ecology, 65, pp. 205-210Gentry, G.L., Dyer, L.A., On the conditional nature of neotropical caterpillar defenses against their natural enemies (2002) Ecology, 83, pp. 3108-3119Hammer, Ø., Harper, D.A.T., Ryan, P.D., PAST: Paleontological statistics software package for education and data analysis (2001) Palaeontologia Electronica, 4, p. 9. , http://palaeo-electronica.org/2001_1/past/issue1_01.htmHeil, M., McKey, D., Protective ant-plant interactions as model systems in ecological and evolutionary research (2003) Annual Review of Ecology Evolution and Systematics, 34, pp. 425-453Heil, M., Fiala, B., Baumann, B., Linsenmair, K.E., Temporal, spatial and biotic variations in extrafloral nectar secretion by Macaranga tanarius (2000) Functional Ecology, 14, pp. 749-757Hölldobler, B., Wilson, E.O., (1990) The Ants, , Belknap Press, Cambridge, MA(2012), http://www.inmet.gov.br/html/clima.php#, ClimaJeanne, R.L., A latitudinal gradient in rates of ant predation (1979) Ecology, 60, pp. 1211-1224Kaminski, L.A., Freitas, A.V.L., Oliveira, P.S., Interaction between mutualisms: ant-tended butterflies exploit enemy-free space provided by ant-treehopper associations (2010) American Naturalist, 176, pp. 322-334Koptur, S., Experimental evidence for defense of Inga (Mimosoideae) saplings by ants (1984) Ecology, 65, pp. 1787-1793Letourneau, D.K., Passive aggression: an alternative hypothesis for the Piper-Pheidole association (1983) Oecologia, 60, pp. 122-126Letourneau, D.K., Dyer, L.A., Multi-trophic interactions and biodiversity: beetles, ants, caterpillars, and plants (2005) Biotic Interactions in the Tropics: Their Role in the Maintenance of Species Diversity, pp. 366-385. , eds D.F.R.P. Burslem, M.A. Pinard & S.E. Hartley) -. Cambridge University Press, CambridgeLetourneau, D.K., Dyer, L.A., Vega, G.C., Indirect effects of a top predator on a rain forest understory plant community (2004) Ecology, 85, pp. 2144-2152Lill, J.T., Marquis, R.J., The effects of leaf quality on herbivore performance and attack from natural enemies (2001) Oecologia, 126, pp. 418-428Machado, G., Freitas, A.V.L., Larval defence against ant predation in the butterfly Smyrna blomfildia (2001) Ecological Entomology, 26, pp. 436-439Machado, S.R., Morellato, L.P.C., Sajo, M.J., Oliveira, P.S., Morphological patterns of extrafloral nectaries in woody plant species of the Brazilian cerrado (2008) Plant Biology, 10, pp. 660-673Magurran, A.E., (2004) Measuring Biological Diversity, , Wiley-Blackwell, OxfordMody, K., Linsenmair, K.E., Plant-attracted ants affect arthropod community structure but not necessarily herbivory (2004) Ecological Entomology, 29, pp. 217-225Mooney, K.A., Pratt, R.T., Singer, M.S., The tri-trophic interactions hypothesis: interactive effects of host plant quality, diet breadth and natural enemies on herbivores (2012) PLoS One, 7, p. e34403Oliveira, P.S., The ecological function of extrafloral nectaries: herbivore deterrence by visiting ants and reproductive output in Caryocar brasiliense (Caryocaraceae) (1997) Functional Ecology, 11, pp. 323-330Oliveira, P.S., Brandão, C.R.F., The ant community associated with extrafloral nectaries in the Brazilian cerrados (1991) Ant-Plant Interactions, pp. 198-212. , eds C.R. Huxley & D.F. Cutler) -. Oxford University Press, OxfordOliveira, P.S., Freitas, A.V.L., Ant-plant-herbivore interactions in the neotropical cerrado savanna (2004) Naturwissenschaften, 91, pp. 557-570Oliveira, P.S., Leitão-Filho, H.F., Extrafloral nectaries: their taxonomic distribution and abundance in the woody flora of cerrado vegetation in southeast Brazil (1987) Biotropica, 19, pp. 140-148Oliveira, P.S., Oliveira-Filho, A.T., Distribution of extrafloral nectaries in the woody flora of tropical communities in Western Brazil (1991) Plant-Animal Interactions: Evolutionary Ecology in Tropical and Temperate Regions, pp. 163-175. , eds P.W. Price, T.M. Lewinsohn, G.W. Fernandes & W.W. Benson)-. John Wiley & Sons, New YorkOliveira-Filho, A.T., Ratter, J.A., Vegetation physiognomies and woody flora of the cerrado biome (2002) The Cerrados of Brazil: Ecology and Natural History of a Neotropical Savanna, pp. 91-120. , eds P.S. Oliveira & R.J. Marquis) -. Columbia University Press, New YorkPemberton, R.W., Lee, J.H., The influence of extrafloral nectaries on parasitism of an insect herbivore (1996) American Journal of Botany, 83, pp. 1187-1194Price, P.W., Bouton, C.E., Gross, P., McPheron, B.A., Thompson, J.N., Weis, A.E., Interactions among three trophic levels: influence of plants on interactions between insect herbivores and natural enemies (1980) Annual Review of Ecology and Systematics, 11, pp. 41-65(2012) R: A Language and Environment for Statistical Computing, , R Foundation for Statistical Computing, Vienna, AustriaRibas, C.R., Schoereder, J.H., Pic, M., Soares, S.M., Tree heterogeneity, resource availability, and larger scale processes regulating arboreal ant species richness (2003) Austral Ecology, 28, pp. 305-314Rico-Gray, V., Oliveira, P.S., (2007) The Ecology and Evolution of Ant-Plant Interactions, , University of Chicago Press, ChicagoRudgers, J.A., Enemies of herbivores can shape plant traits: selection in a facultative ant-plant mutualism (2004) Ecology, 85, pp. 192-205Schmitz, O.J., Krivan, V., Ovadia, O., Trophic cascades: the primacy of trait-mediated indirect interactions (2004) Ecology Letters, 7, pp. 153-163Schoereder, J.H., Sobrinho, T.G., Madureira, M.S., Ribas, C.R., Oliveira, P.S., The arboreal ant community visiting extrafloral nectaries in the Neotropical cerrado savanna (2010) Terrestrial Arthropod Reviews, 3, pp. 3-27Sendoya, S.F., Freitas, A.V.L., Oliveira, P.S., Egg-laying butterflies distinguish predaceous ants by sight (2009) American Naturalist, 174, pp. 134-140Sendoya, S.F., Oliveira, P.S., Data from: Ant-caterpillar antagonism at the community level: interhabitat variation of tritrophic interactions in a neotropical savannah (2014) Dryad Digital RepositorySinger, M.S., Farkas, T.E., Skorik, C.M., Mooney, K.A., Tritrophic interactions at a community level: effects of host plant species quality on bird predation of caterpillars (2012) American Naturalist, 179, pp. 363-374Smiley, J.T., Heliconius caterpillar mortality during establishment on plants with and without attending ants (1985) Ecology, 66, pp. 845-849Styrsky, J.D., Eubanks, M.D., Ecological consequences of interactions between ants and honeydew-producing insects (2007) Proceedings of the Royal Society B, Biological Sciences, 274, pp. 151-164Thompson, J.N., (2005) The Geographic Mosaic of Coevolution, , The University of Chicago Press, ChicagoThompson, J.N., Pellmyr, O., Evolution of oviposition behavior and host preference in Lepidoptera (1991) Annual Review of Entomology, 36, pp. 65-89Tillberg, C.V., Friend or foe? A behavioral and stable isotopic investigation of an ant-plant symbiosis (2004) Oecologia, 140, pp. 506-515Tobin, J.E., Ecology and diversity of tropical forest canopy ants (1995) Forest Canopies, pp. 129-147. , eds M.D. Lowman & N.M. Nadkarni) -. Academic Press, New York(2002) Multitrophic Level Interactions, , Tscharntke, T. & Hawkins, B.A. (eds) () . Cambridge University Press, CambridgeZuur, A.F., Ieno, E.N., Walker, N., Saveliev, A.A., Smith, G.M., (2009) Mixed Effects Models and Extensions in Ecology with R, , Springer, Dordrecht