Summary
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1.
African weaver ants (Oecophylla longinoda) utilize no less than five recruitment systems to draw nestmates from the leaf nests to the remainder of the nest tree and to the foraging areas beyond: (a) recruitment to new food sources, mediated by odor trails produced from the rectal gland, a newly discovered exocrine organ, together with tactile stimuli presented during mouth-opening, antennation, and head-waggling; (b) recruitment to new terrain, entailing odor trails released from the rectal gland and tactile stimulation through antennation: (c) emigration to new sites; (d) short-range recruitment to territorial intruders, during which the terminal abdominal sternite is maximally exposed and dragged for short distances over the ground to release an attractant from the sternal gland, a second newly discovered structure; and (e) long-range recruitment to intruders, mediated by odor trails from the rectal gland and by antennation and intense body jerking.
These systems exist in addition to the elaborate pheromone-mediated alarm communication previously described by Bradshaw et al. (1975). In aggregate, the alarm and recruitment systems of O. longinoda constitute the most complex of such repertories thus far discovered in ants.
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2.
Weaver ants recognize new terrain by means of both visual and olfactory cues, with the latter being the more effective. When major workers cannot cross gaps to the terrain by walking, they attempt to make the traverse by building bridges with their bodies. Individuals are attracted to the bridge site visually, but when the bridge is complete, they recruit nestmates to the new terrain with rectal-gland odor trails.
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3.
Workers mark newly acquired home range with randomly placed drops of fluid extruded from the rectal vesicle. They distinguish their own domain from that of alien conspecific colonies in part by means of the odor of the anal spots. When a section of terrain is found unmarked, the rate of anal-drop deposition is accelerated, even when adjacent areas are already heavily marked.
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4.
The anal substance is a true territorial pheromone: workers respond to alien spots initially with hostility and aversion, then by recruiting nestmates to the vicinity. In laboratory experiments, workers entering an arena simultaneously with workers from alien colonies always gained the initial advantage in the ensuing conflict if they had previously been allowed to mark the arena. When the arena was placed in a spatial position familiar to one colony but possessed a floor previously marked by the second colony, the second colony still won. To our knowledge these results represent the first demonstration of a true territorial pheromone in the social insects.
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5.
During foraging the Oecophylla workers move independently of one another and are distributed at random (Poisson distributed) or with slight temporary clumping of no more than two or three workers. Short-range recruitment of intruders causes the ants to shift to a more distinctly clumped pattern, involving as many as ten or more workers, at the same time that long-range recruitment brings more defenders into the vicinity. Together the two forms of response result in a more efficient capture of intruders that are too large to be immobilized by only one or two workers.
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6.
The complex recruitment and territorial behavior displayed by O. longinoda is considered to be part of the adaptation of these relatively large ants to a strongly arboreal existence. The similarity of four of the recruitment systems to each other (1 a, b, c, and e above) is interpreted as an example of signal economy in the evolution of social insect communication systems. The parallel evolution has been enhanced by the lack of any strong functional distinction between territorial defense and predation (see Discussion).
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6.
Signal ritualization appears to have occurred in at least two contexts: the modification of body thrusting during territorial battles into the jerking signal used in long-range recruitment of nestmates to enemies; and the adoption of anal excrement in the chemical marking of territories.
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References
Bradshaw, J.W.S., Baker, R., Howse, P.E.: Multicomponent alarm pheromones of the weaver ant. Nature 258, 230–231 (1975)
Gotwald, W.H., Jr.: Oecophylla longinoda, an ant predator of Anomma driver ants (Hymenoptera: Formicidae). Psyche (Cambridge, Mass.) 79, 348–356 (1972)
Hemmingsen, A.M.: Nocturnal weaving on nest surface and division of labour in weaver ants (Oecophylla smaragdina Fabricius, 1775). Vidensk. Meddr. Dansk Naturh. Foren. 136, 49–56 (1973)
Hölldobler, B.: Recruitment behavior, home range orientation and territoriality in harvester ants, Pogonomyrmex. Behav. Ecol. Sociobiol. 1, 3–44 (1976a)
Hölldobler, B.: Tournaments and slavery in a desert ant. Science 192, 912–914 (1976b)
Hölldobler, B.: Communication in social Hymenoptera. In: How animals communicate (ed. T.A. Sebeok), pp. 418–471. Bloomington, Indiana: Indiana University Press 1977
Hölldobler, B., Wilson, E.O.: Weaver ants: social establishment and maintenance of territory. Science 195, 900–902 (1976)
Jones, R.B., Nowell, N.W.: The urinary aversive pheromone of mice: species, strain, and grouping effects. Anim. Behav. 22, 187–191 (1974)
Ledoux, A.: Recherche sur la biologie de la fourmi fileuse (Oecophylla longinoda Latr.). Ann. Sci. Nat., ser. 11 12 (3–4), 313–461 (1950)
Leston, D.: Ants, capsids and swollen shoot in Ghana: interactions and the implications for pest control. Proc. 3rd Int. Cocoa Res. Conf., Accra, pp. 205–221 (1969)
Leston, D.: Entomology of the cocoa farm. Ann. Rev. Entomol. 15, 273–295 (1970)
Leston, D.: The ant mosaic-tropical tree crops and the limiting of pests and diseases. Pest Articles and News Summaries, Centre for Overseas Pest Research, London 19 (3), 311–341 (1973)
Mackintosh, J.H.: Factors affecting the recognition of territorial boundaries by mice (Mus musculus). Anim. Behav. 21, 464–470 (1973)
Maschwitz, U.: Old and new trends in the investigation of chemical recruitment in ants. In: Symposium of the International Union for Study of Social Insects: Pheromones and defensive secretions in social insects, pp. 47–59. Dijon, University of Dijon 1975
Mykytowycz, R.: Territorial marking by rabbits. Sci. Amer. 218, 116–126 (1968)
Peters, R.P., Mech, L.D.: Scent-marking in wolves. Amer. Sci. 63, 628–637 (1975)
Room, P.M.: The relative distribution of ant species in Ghana's cocoa farms. J. Anim. Ecol. 40, 735–751 (1971)
Shorey, H.H.: Animal communication by pheromones. New York: Academic Press 1976
Way, M.J.: Studies of the life history and ecology of the ant Oecophylla longinoda Latreille. Bull. ent. Res. 45, 93–112 (1954)
Wheeler, W.M.: Ants of the American Museum Congo Expedition. A contribution to the myrmecology of Africa. VIII. A synonymic list of the ants of the Ethiopian Region. Bull. Amer. Mus. Nat. Hist. 45, 711–1004 (1922)
Wilson, E.O.: The insect societies. Cambridge, Massachusetts. Belknap Press of Harvard University Press 1971
Wilson, E.O., Taylor, R.W.: A fossil ant colony: new evidence of social antiquity. Psyche (Cambridge, Mass.) 71, 93–103 (1964)
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Hölldobler, B., Wilson, E.O. The multiple recruitment systems of the african weaver ant Oecophylla longinoda (Latreille) (Hymenoptera: Formicidae). Behav Ecol Sociobiol 3, 19–60 (1978). https://doi.org/10.1007/BF00300045
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DOI: https://doi.org/10.1007/BF00300045