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Context dependency of rewards and services in an Indian ant–plant interaction: southern sites favour the mutualism between plants and ants

  • Joyshree Chanam (a1), Srinivasan Kasinathan (a1), Gautam K. Pramanik (a1), Amaraja Jagdeesh (a1), Kanchan A. Joshi (a1) and Renee M. Borges (a1)...

Protection-based ant–plant mutualisms may vary in strength due to differences in ant rewards, abundance of protective ants and herbivory pressure. We investigated geographical and temporal variation in host plant traits and herbivory pressure at five sites spanning the distribution range of the myrmecophyte Humboldtia brunonis (Fabaceae) in the Indian Western Ghats. Southern sites had, on average, 2.4 times greater abundance of domatia-bearing individuals, 1.6 times greater extrafloral nectary numbers per leaf, 1.2 times larger extrafloral nectary sizes, 2.2 times greater extrafloral nectar (EFN) volumes and a two-fold increase in total amino acid and total sugar concentrations in EFN compared with northern sites. A strong protection-based mutualism with ants occurred at only one southern site where herbivory was highest, suggesting that investments in attracting ants correlate with anti-herbivore benefits gained from the presence of protective ants. Our results confirm a temporally stable north–south gradient in myrmecophytic traits in this ant-plant as several of these traits were re-sampled after a 5-y interval. However, the chemical composition of EFN varied at both spatial and short-term temporal scales suggesting that only repeated measurements of rewards such as EFN can reveal the real spectrum of trait variation in an ant–plant mutualistic system.

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ARAVIND, N. A., GANESHAIAH, K. N. & UMA SHAANKER, R. 2013. Indian monsoons shape dispersal phenology of plants. Biology Letters 9:20130675.
BAKER-MÉIO, & MARQUIS, R. J. 2012. Context-dependent benefits from ant–plant mutualism in three sympatric varieties of Chamaecrista desvauxii . Journal of Ecology 100:242252.
BARTON, A. M. 1986. Spatial variation in the effect of ants on an extrafloral nectary plant. Ecology 67:495504.
BIXENMANN, R. J., COLEY, P. D. & KURSAR, T. A. 2011. Is extrafloral nectar production induced by herbivores or ants in a tropical facultative ant–plant mutualism? Oecologia 165:417425.
BLATRIX, R., RENARD, D., DJIETO-LORDON, C. & McKEY, D. 2012. The cost of myrmecophytism: insights from allometry of stem secondary growth. Annals of Botany 110: 943951.
BRONSTEIN, J. L. 1994. Conditional outcomes in mutualistic interactions. Trends in Ecology and Evolution 9:214217.
BROUAT, C. & MCKEY, D. 2000. Origin of caulinary ant domatia and timing of their onset in plant ontogeny: evolution of a key trait in horizontally transmitted ant–plant symbioses. Biological Journal of the Linnean Society 71:801819.
CHAMBERLAIN, S. A. & HOLLAND, N. J. 2008. Density-mediated, context-dependent consumer-resource interactions between ants and extrafloral nectar plants. Ecology 89:13641374.
CHANAM, J., SHESHSHAYEE, M. S., KASINATHAN, S., JAGDEESH, A., JOSHI, K. A. & BORGES, R. M. 2014. Nutritional benefits from domatia inhabitants in an ant–plant interaction: interlopers do pay the rent. Functional Ecology doi: 10.1111/1365–2435.12251
CRAWLEY, M. J. 2012. The R book. John Wiley & Sons. 942 pp.
DAVIDAR, P., PUYRAVAUD, J. P. & LEIGH, E. G. JR. 2005. Changes in rain forest tree diversity, dominance and rarity across a seasonality gradient in the Western Ghats, India. Journal of Biogeography 32:493501.
DEV, S. A., SHENOY, M. & BORGES, R. M. 2010. Genetic and clonal diversity of the endemic ant-plant Humboldtia brunonis (Fabaceae) in the Western Ghats of India. Journal of Biosciences 35:267279.
DÍAZ-CASTELAZO, C., SÁNCHEZ-GALVÁN, I. R., GUIMARÃES, P. R., RAIMUNDO, R. L. G. & RICO-GRAY, R. 2013. Long-term temporal variation in the organization of an ant–plant network. Annals of Botany 111:12851293.
ESCALANTE-PÉREZ, M., JABORSKY, M., LAUTNER, S., FROMM, J., MÜLLER, T., DITTRICH, M., KUNERT, M., BOLAND, W., HEDRICH, R. & ACHE, P. 2012. Poplar extrafloral nectaries: two types, two strategies of indirect defenses against herbivores. Plant Physiology 159:11761191.
FIALA, B. & MASCHWITZ, U. 1992. Domatia as most important adaptations in the evolution of myrmecophytes in the paleotropical tree genus Macaranga (Euphorbiaceae). Plant Systematics and Evolution 180:5364.
FONSECA, C. R. 1999. Amazonian ant-plant interactions and the nesting space limitation hypothesis. Journal of Tropical Ecology 15:807825.
GADGIL, S. & JOSHI, N. V. 1983. Climatic clusters of the Indian region. Journal of Climatology 3:4753.
GAUME, L., ZACHARIAS, M., GROSBOIS, V. & BORGES, R. M. 2005. The fitness consequences of bearing domatia and having the right ant partner: experiments with protective and non-protective ants in a semi-myrmecophyte. Oecologia 145:7686.
GAUME, L., SHENOY, M., ZACHARIAS, M. & BORGES, R. M. 2006. Co-existence of ants and an arboreal earthworm in a myrmecophyte of the Indian Western Ghats: anti-predation effects of the earthworm mucus. Journal of Tropical Ecology 22:341344.
GOMULKIEWICZ, R., THOMPSON, J. N., HOLT, R. D., NUISMER, S. L. & HOCHBERG, M. E. 2000. Hot spots, cold spots, and the geographic mosaic theory of coevolution. American Naturalist 156:156174.
GONZÁLEZ-TEUBER, M., SILVA BUENO, J. C., HEIL, M. & BOLAND, W. 2012. Increased host investment in extrafloral nectar (EFN) improves the efficiency of a mutualistic defensive service. PLoS One 7 (10): e46598.
HEIL, M., FIALA, B., BAUMANN, B. & LINSENMAIR, K. E. 2000. Temporal, spatial and biotic variations in extrafloral nectar secretion by Macaranga tanarius . Functional Ecology 14:749757.
HEIL, M., KOCH, T., HILPERT, A., FIALA, B., BOLAND, W. & LINSENMAIR, K. E. 2001. Extrafloral nectar production of the ant-associated plant, Macaranga tanarius, is an induced, indirect, defensive response elicited by jasmonic acid. Proceedings of the Royal Society of London. Series B: Biological Sciences 98:1083–1088.
KERSCH, M. F. & FONSECA, C. R. 2005. Abiotic factors and the conditional outcome of an ant–plant mutualism. Ecology 86:21172126.
KOST, C. & HEIL, M. 2005. Increased availability of extrafloral nectar reduces herbivory in Lima bean plants (Phaseolus lunatus, Fabaceae). Basic and Applied Ecology 6:237248.
KROMBEIN, K. V., NORDEN, B. B., RICKSON, M. M. & RICKSON, F.R. 1999. Biodiversity of the domatia occupants (ants, wasps, bees, and others) of the Sri Lankan myrmecophyte Humboldtia laurifolia Vahl (Fabaceae). Smithsonian Contributions to Zoology 603:134.
MONDOR, E. B., TREMBLAY, M. N. & MESSING, R. H. 2006. Extrafloral nectary phenotypic plasticity is damage-and resource-dependent in Vicia faba . Biology Letters 2:583585.
PASCAL, J. P. 1988. Wet evergreen forests of the Western Ghats of India. Ecology, structure, floristic composition and succession. French Institute, Pondicherry. 342 pp.
PEMBERTON, R. W. 1998. The occurrence and abundance of plants with extrafloral nectaries, the basis for antiherbivore defense mutualisms, along a latitudinal gradient in East Asia. Journal of Biogeography 25:661668.
PRINGLE, E. G. & GORDON, D. M. 2013. Protection mutualism and the community: geographic variation in an ant-plant symbiosis and the consequences for herbivores. Sociobiology 60:242251.
PULICE, C. E. & PACKER, A. A. 2008. Simulated herbivory induces extrafloral nectary production in Prunus avium . Functional Ecology 22:801807.
RAI, S. N. 2000. Productivity of tropical rain forests of Karnataka. Eastern Press, Bangalore. 128 pp.
RICO-GRAY, V. & OLIVEIRA, P. S. 2007. The ecology and evolution of ant–plant interactions. University of Chicago Press, Chicago. 200 pp.
RICO-GRAY, V., GARCIA-FRANCO, J. G., PALACIOS-RIOS, M., DÍAZ-CASTELAZO, C., PARRA-TABLA, V. & NAVARRO, J. A. 1998. Geographical and seasonal variation in the richness of ant-plant interactions in Mexico. Biotropica 30:190200.
RICO-GRAY, V., DÍAZ-CASTELAZO, C., RAMÍREZ-HERNÁNDEZ, A., GUIMARÃES, P. R. & HOLLAND, J. N. 2012. Abiotic factors shape temporal variation in the structure of an ant–plant network. Arthropod–Plant Interactions 6:289295.
RIOS, R. S., MARQUIS, R. J. & FLUNKER, J. C. 2008. Population variation in plant traits associated with ant attraction and herbivory in Chamaecrista fasciculata (Fabaceae). Oecologia 156:577588.
RUDGERS, J. A. 2004. Enemies of herbivores can shape plant traits: selection in a facultative ant–plant mutualism. Ecology 85:192205.
RUDGERS, J. A. & GARDENER, M. C. 2004. Extrafloral nectar as a resource mediating multispecies interactions. Ecology 85:14951502.
RUDGERS, J. A. & STRAUSS, S. Y. 2004. A selection mosaic in the facultative mutualism between ants and wild cotton. Proceedings of the Royal Society of London. Series B: Biological Sciences 271:2481–2488.
SHENOY, M. 2008. Spatial variation in interactions of the semi-myrmecophyte Humboldtia brunonis (Fabaceae) with ants and other invertebrates. PhD dissertation, Indian Institute of Science, Bangalore, India.
SHENOY, M. & BORGES, R. M. 2010. Geographical variation in an ant–plant interaction correlates with domatia occupancy, local ant diversity, and interlopers. Biological Journal of the Linnean Society 100:538551.
SHENOY, M., RADHIKA, V., SATISH, S. & BORGES, R. M. 2012. Composition of extrafloral nectar influences interactions between the myrmecophyte Humboldtia brunonis and its ant associates. Journal of Chemical Ecology 38:8899.
SUPPIAH, R. 1996. Spatial and temporal variations in the relationships between the Southern Oscillation phenomenon and the rainfall of Sri Lanka. International Journal of Climatology 16:13911407.
THOMPSON, J. N. 1999. Specific hypotheses on the geographic mosaic of coevolution. American Naturalist 153:S1–S14.
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