The Microbiome of Leaf-Cutter Ant Fungus Gardens
Garret Suen, Jarrod J. Scott, Frank O. Aylward, Cameron R. Currie
(2011).
in Handbook of Molecular Microbial Ecology II: Metagenomics in Different Habitats, 367--379.
Abstract
The evolution of fungus farming in ants has a single, Amazonian origin dating to the climactic optimum of the early Eocene epoch (∼50 million years ago). By co-opting the degradation abilities of fungi, this protofarmer was freed from many of the limitations associated with a reliance on unpredictable food supplies. The fungus metabolizes and transforms a variety of plant biomass into nutrients suitable for ant consumption, material that is often inac- cessible to direct digestion by many except the most spe- cialized of insect species. The evolutionary transition to fungus farming permitted these ants to diversify, giving rise to the monophyletic tribe Attini, which presently con- sists of >230 extant species in 13 genera. Over time, multiple types of agricultural systems evolved, culminating in the leaf-cutter ants (Atta and Acromyrmex ) around 10 million years ago. These ants are arguably one of the most prodigious insect societies in nature.