Load Capacity of Workers of Atta robusta During Foraging (Hymenoptera: Formicidae)

Ana Maria Viana Bailez


Worker ants are highly polymorphic in the genus Atta and they are usually classified into castes according to the specific functions they perform in a colony. Minor workers (head width ≤ 2.0 mm) help to maintain and grow the symbiotic fungus whereas larger workers (head width > 2.0 mm) cut and transport plant fragments. This study investigated the roles in the cutting and transporting of different plant resources of different Atta robusta worker classes that were classified based on the size of their head capsule. Experiments were conducted in the restinga of Grussaí/Iquipari, São João da Barra, Rio de Janeiro State, Brazil. In each month between October 2009 and September 2010, we collected 100 ants and their respective loads from the trails of four nests of Atta robusta. The samples were individually transported to the laboratory, where the ants and their loads were weighed and the head capsules of the ants were measured. Large ants transported heavier loads. These ants usually transported more fruit and seeds than smaller ants.


leaf-cutting ants; Atta robusta; resting; load transport; polymorphism

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Christianini, A.V. & Oliveira P.S. 2009. The relevance of ants as seed rescuers of a primarily bird-dispersed tree in the Neotropical cerrado savanna. Oecologia 160: 735-745.

Dussutour, A., Deneubourg, J., Beshers, S., Fourcassié, V. 2009. Individual and collective problem-solving in a foraging context in the leaf-cutting ant Atta colombica. Animal Cognition. 12 (1): 21-30.

Evison, S.E.F. & F.L.W. Ratnieks 2007. New role for largers in Atta leafcutter ants. Ecological Entomology 32: 451–454.

Forti, L.C., R.S. Camargo, C.A.O. Matos, A.P.P. Andrade & J.F. Lopes 2004. Aloetismo em Acromyrmex subterraneus brunneus Forel (Hymenoptera, Formicidae), durante o forrageamento, cultivo do jardim de fungo e devolução dos materiais forrageados Revista Brasileira de Entomologia 48: 59-63.

Helanterä, H. & F.L.W. Ratnieks 2008. Geometry explains the benefits of division of labour in a leafcutter ant. Proceedings of the Royal Society 275: 1255-1260.

Hölldobler, B. & E.O. Wilson 1990. The ants. The Belknap Press of Harvard University, Cambridge, Massachusetts. 732 p.

Kleineidam, C.J., W. Rössler, B. Hölldobler & F. Roces 2007. Perceptual differences in trail-following leaf-cutting ants relate to body size. Journal of Insect Physiology 53: 1233-1241.

Leal, I.P. & P.S. Oliveira 1998. Interactions between fungus-growing ants (Attini), fruits and seeds in cerrado vegetation in Southeast Brazil. Biotropica 30: 70-178.

Leal, I.R. & P.S. Oliveira 2000. Foraging ecology of attine ants in a Neotropical savanna: seasonal use of fungal substrate in the cerrado vegetation of Brazil. Insectes Sociaux 47: 376–382.

Lighton, J.B.R., G.A. Bartholomew & D.H. Feener Jr 1987. Energetics of locomotion and load carriage and a model of the energy cost of foraging in the leaf-cutting ant, Atta colombica. Guer. Physiological Zoology 60: 524-537.

Moreira, D.D.O., A.M. Viana- Bailez, M. Erthal Jr., O. Bailez, M.P. Carrera & R.I. Samuels 2010. Resource allocation among worker castes of the leaf-cutting ants Acromyrmex subterraneus subterraneus through trophallaxis. Journal of Insect Physiology 56: 1665- 1670.

Roces, F. & B. Hölldobler 1994. Leaf density and a trade-off between load-size selection andrecruitment behavior in the ant Atta cephalotes. Oecologia 97: 1-8.

Röschard J. & F. Roces 2003. Fragment-size determination and size-matching in thegrasscutting ant Atta vollenweideri depend on the distance from the nest. Journal of Tropical Ecology 19: 647-653.

Teixeira, M.C. 2007. Dispersão de sementes por Atta robusta Borgmeier 1939 (Hymenoptera: Formicidade) na restinga da Ilha de Guriri. Tese (Doutorado em Entomologia) – Viçosa – MG, Universidade Federal de Viçosa - UFV, 72p.

Wetterer, J.K. 1990. Load size determination in the leaf-cutting ant, Atta cephalotes. Behavioral Ecology 1: 95-101.

Wetterer, J.K. 1992. Foraging ecology of the leaf-cutting ant Acromyrmex octospinosus in a Costa Rican rain forest. Psyche 98 :361-371.

Wilson, E. O. 1971. The insects societies. Cambrige: Harvard University Press 1971, 548p.

Wilson, E.O. 1980. Caste and division of labor in leaf-cutter ants (Hymenoptera: Formicidae: Atta) - I. The overall pattern in A. sexdens. Behavioral Ecology and Sociobiology 7: 143-156.

Wilson, E.O. 1985. The sociogenesis of insect colonies. Science 228: 1489-1495.

DOI: http://dx.doi.org/10.13102/sociobiology.v59i3.551


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