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Specialization Does Not Predict Individual Efficiency in an Ant

By Anna Dornhaus


The ecological success of social insects is often attributed to an increase in efficiency achieved through division of labor between workers in a colony. Much research has therefore focused on the mechanism by which a division of labor is implemented, i.e., on how tasks are allocated to workers. However, the important assumption that specialists are indeed more efficient at their work than generalist individuals—the “Jack-of-all-trades is master of none” hypothesis—has rarely been tested. Here, I quantify worker efficiency, measured as work completed per time, in four different tasks in the ant Temnothorax albipennis: honey and protein foraging, collection of nest-building material, and brood transports in a colony emigration. I show that individual efficiency is not predicted by how specialized workers were on the respective task. Worker efficiency is also not consistently predicted by that worker's overall activity or delay to begin the task. Even when only the worker's rank relative to nestmates in the same colony was used, specialization did not predict efficiency in three out of the four tasks, and more specialized workers actually performed worse than others in the fourth task (collection of sand grains). I also show that the above relationships, as well as median individual efficiency, do not change with colony size. My results demonstrate that in an ant species without morphologically differentiated worker castes, workers may nevertheless differ in their ability to perform different tasks. Surprisingly, this variation is not utilized by the colony—worker allocation to tasks is unrelated to their ability to perform them. What, then, are the adaptive benefits of behavioral specialization, and why do workers choose tasks without regard for whether they can perform them well? We are still far from an understanding of the adaptive benefits of division of labor in social insects

Topics: Research Article
Publisher: Public Library of Science
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Provided by: PubMed Central

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  7. BeshersSN,HuangZY,OonoY,RobinsonGY(2001) Socialinhibitionand the regulation of temporal polyethism in honey bees.
  8. (1979). Bumblebee economics. Cambridge (Massachusetts):
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  10. (1980). Caste and division of labor in leaf-cutter ants (Hymenoptera: Formicidae: Atta) II. The ergonomic optimization of leaf cutting.
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  12. (2005). Caste evolution and ecology: a special worker for novel prey.
  13. (1993). Caste specialization in food storage in the dimorphic ant Colobopsis nipponicus (Wheeler).
  14. (1987). Causes of ecological success: the case of the ants.
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  26. (1985). Fire ant polymorphism: the ergonomics of brood production.
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  32. (1991). Genetic differences in learning behavior in honeybees (Apis mellifera capensis).
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  51. Rissing SW (2005) Division of foraging labor in ants can mediate demands for food and safety.
  52. (1999). Self-assembly, self-organization and division of labour.
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  54. (1989). Social organization in the ant Pheidole dentata: Physical and temporal caste ratios lack ecological correlates.
  55. (2005). Sociogenomics: social life in molecular terms.
  56. (1995). Spatial relationships within nests of the ant Leptothorax unifasciatus (Latr.) and their implications for the division of labour.
  57. (2004). Sucrose responsiveness and behavioral plasticity in honey bees (Apis mellifera).
  58. (1993). Task allocation in ant colonies within variable environments (a study of temporal polyethism,
  59. (1990). The ants:
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  61. (2006). The fire ants.
  62. (1976). The foraging specializations of individual bumblebees.
  63. (2006). The genetic architecture of sucrose responsiveness in the honeybee (Apis mellifera L.).
  64. (1987). The guard honey bee: ontogeny and behavioural variability of workers performing a specialized task.
  65. (1986). The organization of work in Polybia occidentalis: costs and benefits of specialization in a social wasp.
  66. (1996). The organization of work in social insect colonies.
  67. (2002). The relationship between the distribution of worker sizes and new worker production in the ant Formica neorufibarbis.
  68. (2006). The role of mechanosensory input in flower handling efficiency and learning by Manduca sexta.
  69. (1999). The role of orientation flights on homing performance in honeybees.
  70. (1985). The sociogenesis of insect colonies.
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  74. (2002). Weidenmu ¨ller A
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  76. (2007). Worker caste determination in the army ant Eciton burchellii.
  77. (1992). Worker castes and adaptive demography.

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