, Volume 90, Issue 6, pp 277–281 | Cite as

Size-correlated division of labour and spatial distribution of workers in the driver ant, Dorylus molestus

  • Christian Braendle
  • Neal Hockley
  • Thomas Brevig
  • Alexander W. Shingleton
  • Laurent Keller
Short Communication


Driver ants (Dorylus spp.) show a high degree of worker polymorphism. Previous reports suggest that large Dorylus workers are specialised for defensive tasks. In this study, we first quantitatively tested whether there is a size-correlated division of defensive labour among workers. Second, we determined whether the spatial distribution of workers outside the nest can be predicted based on such size-specific differences in task allocation. We show that the division of defensive behaviour among different-sized workers is not strict. However, there is a significant correlation between worker size and the tendency to carry out defensive tasks. First, workers of larger size were more likely than smaller workers to participate in colony defence. Second, larger workers were more frequent near the nest containing the reproducing individuals and the brood. Finally, large workers were more common in open sections of the trail than in covered sections, which are likely to be less exposed to predators.


Nest Site Head Width Large Worker Small Worker Work Size 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This study was conducted during a Darwin Course in Tropical Biology organised by the Tropical Biology Association (TBA). We thank the TBA, in particular Rosie Trevelyan, for their support. William Gotwald, Jr., kindly identified the ant specimens. We thank Thomas Flatt for helpful comments on earlier versions of the manuscript. C.B. was funded by the Swiss Study Foundation, the Olga and Joseph-Tomscik Foundation, and the British Ecological Society (BES). T.B. was supported by funds from the University of Oslo via Nils Christian Stenseth, and the BES. L.K. was funded by grants from the Swiss NSF.


  1. Cerdá X, Retana J (1997) Links between worker polymorphism and thermal biology in a thermophilic ant species. Oikos 78:467–474Google Scholar
  2. Gotwald WH Jr (1974) Predatory behaviour and food preferences of driver ants in selected African habitats. Ann Entomol Soc Am 67:877–886Google Scholar
  3. Gotwald WH Jr (1995) Army ants: the biology of social predation. Cornell University Press, Ithaca, N.Y.Google Scholar
  4. Humle T, Matsuzawa T (2002) Ant-dipping among the chimpanzees of Bossou, Guinea, and some comparisons with other sites. Am J Primatol 58:133–148CrossRefPubMedGoogle Scholar
  5. Oster GF, Wilson EO (1978) Caste and ecology in the social insects. Princeton University Press, Princeton, N.J.Google Scholar
  6. Raignier A, Boven JKA van (1955) Etude taxonomique, biologique et biometrique des Dorylus du sous-genre Anomma (Hymenoptera Formicidae). Ann Mus R Congo Belge 2:1–359Google Scholar
  7. Sokal RF, Rohlf FJ (1995) Biometry. Freeman, New YorkGoogle Scholar

Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • Christian Braendle
    • 1
    • 5
  • Neal Hockley
    • 1
  • Thomas Brevig
    • 2
  • Alexander W. Shingleton
    • 3
  • Laurent Keller
    • 4
  1. 1.Department of ZoologyUniversity of CambridgeCambridgeUK
  2. 2.Department of BiologyUniversity of OsloOsloNorway
  3. 3.Department of Ecology and Evolutionary BiologyPrinceton UniversityPrincetonUSA
  4. 4.Institute of EcologyUniversity of LausanneLausanneSwitzerland
  5. 5.Department of Ecology and Evolutionary BiologyPrinceton UniversityPrincetonUSA

Personalised recommendations