Insectes Sociaux

, Volume 61, Issue 4, pp 367–369 | Cite as

Morphological differences between extranidal and intranidal workers in the ant Temnothorax rugatulus, but no effect of body size on foraging distance

  • J. N. Westling
  • K. Harrington
  • S. Bengston
  • A. Dornhaus
Research Article


Most ant genera are thought to have monomorphic workers, indicating perhaps a high degree of flexibility in task allocation, and the well-studied genus Temnothorax is an example of this. However, considerable size variation may exist between individuals. In addition, though workers can show flexible behavior, it has been shown that individuals may consistently differ in their task profiles. Here we test whether body size variation among workers affects foraging behavior. Two main hypotheses were tested: first, whether larger ants forage at greater distance from the nest, and second, whether larger individuals show a higher propensity to work outside of the nest. Our results showed that ant body size does not significantly affect foraging distance. However, larger ants were more likely to be found outside the nest. Though Temnothorax ants are a common model system, this is the first study demonstrating task allocation based on body size, which is fixed in adults. Our study suggests that particularly small species may have to be examined carefully for body size variation before concluding that body size is uniform and therefore irrelevant for task allocation.


Task allocation Foraging Size variation Temnothorax Behavioral castes 



We would like to thank the NSF (Grants No. IOS-1045239 and DBI-1262292 to AD) and the University of Arizona Center for Insect Science for funding. Additionally we would like to thank the members of the Dornhaus lab for their helpful feedback.


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Copyright information

© International Union for the Study of Social Insects (IUSSI) 2014

Authors and Affiliations

  • J. N. Westling
    • 1
  • K. Harrington
    • 1
  • S. Bengston
    • 1
  • A. Dornhaus
    • 1
  1. 1.Department of Ecology and Evolutionary BiologyUniversity of ArizonaTucsonUSA

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