A MODEL FOR OSMOTROPOTACTIC ORIENTATION .1.

A phenomenological model for osmotropotactic behaviour in ants and termites is presented. The model concentrates on the physical chemistry of scent trails and the dynamics between a chemical stimulus and the behavioural response at the level of the individual using a non-linear perception-response function. The model reproduces experimental data and shows that a flexible response, saturation at the level of perception and a certain amount of noise are necessary to obtain trail following. The comparison between theoretical and experimental results reveals what factors are important in general for orientation on scent trails. The same model also describes orientation towards point sources. Various examples for collective patterns, which are based on trail following or aggregation, are known in ants and termites. These patterns emerge from the integration of individual behaviour taking into account interactions between the individuals. The model presented can be used for a group of equally equipped individuals and serves thus as a starting point for the description of complex behaviour. © 1992 Academic Press Limited.