Diversity of ant-plant interactions: protective efficacy in Macaranga species with different degrees of ant association

Abstract

The pioneer tree Macaranga in SE Asia has developed manyfold associations with ants. The genus comprises all stages of interaction with ants, from facultative relationships to obligate myrmecophytes. Only myrmecophytic Macaranga offer nesting space for ants and are associated with a specific ant partner. The nonmyrmecophytic species are visited by a variety of different ant species which are attracted by extrafloral nectaries (EFN) and food bodies. Transitional Macaranga species like M. hosei are colonized later in their development due to their stem structure. Before the colonization by their specific Crematogaster partner the young plants are visited by different ant species attracted by EFN. These nectaries are reduced and food body production starts as soon as colonization becomes possible. We demonstrated earlier that obligate ant partners can protect their Macaranga plants against herbivore damage and vine cover. In this study we focused on nonspecific interactions and studied M. tanarius and M. hosei, representing a non-myrmecophyte and a transitional species respectively. In ant exclusion experiments both M. tanarius and M. hosei suffered significantly higher mean leaf damage than controls, 37% versus 6% in M. hosei, 16% versus 7% in M. tanarius. M. tanarius offers both EFN and food bodies so that tests for different effects of these two food rewards could be conducted. Plants with food bodies removed but with EFN remaining had the lowest mean increase of herbivore damage of all experimental groups. Main herbivores on M. hosei were mites and caterpillars. Many M. tanarius plants were infested by a shootborer. Both Macaranga species were visited by various ant species, Crematogaster spp. being the most abundant. We found no evidence for any specific relationships. The results of this study strongly support the hypothesis that non-specific, facultative associations with ants can be advantageous for Macaranga plants. Food bodies appear to have lower attractive value for opportunistic ants than EFN and may require a specific dietary adaptation. This is also indicated by the fact that food body production in the transitional M. hosei does not start before stem structure allows a colonization by the obligate Crematogaster species. M. hosei thus benefits from facultative association with a variety of ants until it produces its first domatia and can be colonized by its obligate mutualist.

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References

  1. Beattie AJ (1985) The evolutionary ecology of ant-plant mutualisms. Cambridge University Press, Cambridge

    Google Scholar 

  2. Davidson DW, Foster RB, Snelling RR, Lozada PW (1991) Variable composition of some tropical ant-plant symbioses. In: Price PW (ed) Herbivory: tropical and temperate perspectives. Wiley, New York, pp 145–162

    Google Scholar 

  3. Fiala B (1991) Partnerschaften von Pflanzen und Ameisen. Biologie Unserer Zeit 5:241–247

    Google Scholar 

  4. Fiala B, Maschwitz U (1990) Studies on the South East Asian ant-plant association Crematogaster borneensis/Macaranga: adaptations of the ant partner. Insectes Soc 37:212–231

    Google Scholar 

  5. Fiala B, Maschwitz U (1991) Extrafloral nectaries in the genus Macaranga (Euphorbiaceae) in Malaysia: comparative studies of their possible significance as predispositions for myrmecophytism. Biol J Linn Soc 44:287–305

    Google Scholar 

  6. Fiala B, Maschwitz U (1992a) Food bodies and their significance for obligate ant-association in the tree genus Macaranga (Euphorbiaceae). Bot J Linn Soc 110:61–75

    Google Scholar 

  7. Fiala B, Maschwitz U (1992b) Domatia as most important adaptations in the evolution of myrmecophytes in the paleotropical tree genus Macaranga (Euphorbiaceae). Plant Syst Evol 180:53–64

    Google Scholar 

  8. Fiala B, Maschwitz U, Tho YP, Helbig AJ (1989) Studies of a South East Asian ant-plant association: protection of Macaranga trees by Crematogaster borneensis. Oecologia 79:463–470

    Google Scholar 

  9. Fiala B, Maschwitz U, Tho YP (1991) The association between Macaranga and ants in South East Asia. In: Huxley C, Cutler DF (eds) Interactions between ants and plants. Oxford University Press, Oxford, pp 263–270

    Google Scholar 

  10. Huxley CR (1986) Evolution of benevolent ant-plant relationships. In: Juniper B, Southwood R (eds) Insects and the plant surface. Arnold, London, pp 257–282

    Google Scholar 

  11. Jones TH, Blum MS, Andersen AN, Fales HM, Escoubas P (1988) Novel 2-ethyl-5-alkylpyrrolidines in the venom of an Australian ant of the genus Monomorium. J Chem Ecol 14:35–45

    Google Scholar 

  12. Keeler KH (1989) Ant-plant interactions. In: Abrahamson WG (ed) Plant-animal interactions. McGraw-Hill, New York, pp 207–242

    Google Scholar 

  13. Koptur S (1979) Facultative mutualism between weedy vetches bearing extrafloral nectaries and weedy ants in California. Am J Bot 66:1016–1020

    Google Scholar 

  14. Koptur S (1992) Extrafloral nectary-mediated interactions between insects and plants. In: Bernays E (ed) Insect-plant interactions, vol IV. CRC Press, Boca Raton, pp 82–129

    Google Scholar 

  15. Letourneau DK, Feynner AG, Jebb M (1993) Coping with enemyfilled space: herbivores on Endospermum in Papua New Guinea. Biotropica 25:95–99

    Google Scholar 

  16. Mackay DA, Whalen MA (1991) Some associations between ants and euphorbs in tropical Australasia. In: Huxley C, Cutler DF (eds) Interactions between ants and plants. Oxford University Press, Oxford, pp 238–249

    Google Scholar 

  17. McKey D (1988) Promising new directions in the study of antplant mutualisms. In: Greuter W, Zimmer B (eds) Proc Int Bot Congr XIV. Koeltz, Koenigstein, pp 335–355

    Google Scholar 

  18. Oliviera PS, Brandão CRF (1991) The ant community associated with extrafloral nectaries in the Brazilian cerrados. In: Huxley CR, Cutler DF (eds) Ant-plant interactions. Oxford University Press, Oxford, pp 198–212

    Google Scholar 

  19. Schupp EW (1986) Azteca protection of Cecropia: ant occupation benefits juvenile trees. Oecologia 70:379–385

    Google Scholar 

  20. Vasconcelos HL (1991) Mutualism between Maieta guianensis Aubl., a myrmecophyte melastome, and one of its ant inhabitants: ant protection against insect herbivores. Oecologia 87:295–298

    Google Scholar 

  21. Whalen MA, Mackay DA (1988) Patterns of ant and herbivore activity on five understory euphorbiaceous saplings in submontane Papua New Guinea. Biotropica 20:294–300

    Google Scholar 

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Correspondence to Brigitte Fiala.

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Fiala, B., Grunsky, H., Maschwitz, U. et al. Diversity of ant-plant interactions: protective efficacy in Macaranga species with different degrees of ant association. Oecologia 97, 186–192 (1994). https://doi.org/10.1007/BF00323148

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Key words

  • Ant-plant interactions
  • Herbivory Macaranga
  • Mutualism
  • Myrmecophytes