Army ants

Watkins, J. F., II, Gehlbach, F. R., and Kroll, J. C. (1969). Attractant-repellent secretions of blind snakes (Leptotyphlops dulcis) and their army ant prey [Neivamyrmexnigrescens). Ecology 50,1098-1102. 

An analogous situation in two dimensions is observable in the behavior of some army ants. They travel in large groups, and when viewed from above, the swarm often looks like a circle. The reason appears to be that the -ants are attracted by the smell of other ants, and hence all try to go to where the smell is strongest, the center. The ants all stay in one plane, so the result is the plane figure with the smallest possible ratio of perimeter to area—a circle [3]. 

Column ojMatahele army ants (Dorylus [Anomma] t x" -wilverthi) en route to raiding a ground termite mound in South Luangwu National Park,... 

One such possibility is the metapleural gland, which Brown (1968) has proposed as the source of colony and species odours. This gland is lost or considerably reduced in species which need to enter the nests of other colonies or species, such as male army ants, workers of Polyergus slave-makers and queens of social parasites. 

Among the few predators of army ants, is the blind snake, Leptotyphlops dulcis, which attacks Neivamyrmex nigrescens and N. opacithorax (Watkins et al., 1969). It is able to locate army ants by following their trails. If attacked by the ants, it releases a cloacal sac secretion containing fatty acids in a slippery... 

LaMon, B. and Topoff, H. (1981) Avoiding predation by army ants defensive behaviour of three ant species of the genus Camponotus. Anim. Behav., 29,1070-81. 

Ray, T. S. and Andrews, C. C. (1980) Antbutterflies butterflies that follow army ants to feed on antbird droppings. Science, 210, 1147-8. 

Schneirla, T. C. (1971) Army Ants a Study in Social Organisation (Topoff, H. R., ed.) Freeman, San Francisco. 

Topoff, H. and Mirenda, J. (1975) Trail-following by the army ant Neivamyrmex ni-grescens responses by workers to volatile odors. Ann. ent. Soc. Am., 68, 1044-6. 

Topoff, H. and Lawson, K. (1979) Orientation of the army ant Neivamyrmex nigrescens integration of chemical and tactile information. Anim. Behav., 27, 429-33. 

Topoff, H. and Mirenda, J. (1980) Army ants do not eat and run influence of food supply on emigration behaviour in Neivamyrmex nigrescens. Anim. Behav., 28, 1040-6. 

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