Random behaviour, amplification processes and number of participants: How they contribute to the foraging properties of ants

Abstract

Two major types of foraging organisation in ants are described and compared, being illustrated with experimental data and mathematical models.The first concerns large colonies of identical, unspecialised foragers. The communication and interaction between foragers and their randomness generates collective and efficient structures. The second concerns small societies of deterministic and specialised foragers, rarely communicating together.The first organisation is discussed in relation to the different recruitment mechanisms, trail-following error, quality and degree of aggregation of food-sources, and territorial marking, and is the key to many types of collective behaviour in social insects. The second is discussed in relation to spatial specialisation, foraging density, individual learning and genetic programming. The two organisations may be associated in the same colony.The choice of organisation is discussed in relation to colony size and size and predictability of food sources.