EVOLUTIONARY ASPECTS OF ANT-FUNGUS INTERACTIONS IN LEAF-CUTTING ANTS

Leaf-cutting ants are highly successful herbivores because they are ab le to use a wide variety of plants as food. The workers harvest and pr ocess plant material to be used as substrate for a fungus on which the y feed. New hypotheses concerning the evolution of the ant-fungus rela tionship have noe been proposed. Although the relationship between the ants and the fungus is mutualistic, it may appear that the fungus has little control over the ants. However, evidence suggests that the fun gus may be exploiting the ants to provide it with substrate and antimi crobial defence. Furthermore, experimental evidence suggests that the fungus can select its substrate by controlling the foraging behaviour of the ants, by means of an ingenious chemical feedback mechanism.