Evolutionary Dynamics of the Mutualistic Symbiosis between Fungus-Growing Termites and Termitomyces Fungi

Abstract Colonies offungus-growing termites (Isoptera: Termitidae) are among the most spectacular organismal phenomena in the world. One of the best-known species offungus-growing termites is Macrotermes bellicosus. A queen of this species (fig. 8.1) can lay up to 40,000 eggs per day, and a mature colony, normally founded by a single queen and king, consists of millions of sterile individuals, the workers and soldiers. Macrotennes bellicosus builds mounds that can be up to 7 m tall (fig. 8.2; Korb 1997). This species and all fungus-growing termites live in an obligate symbiosis with basidiomycete fungi of the genus Tennitomyces. The volume of the fungus garden of a live colony of M. bellicosus has been estimated to encompass several cubic meters. This chapter summarizes recent advances in our understanding of the major macroevolutionary developments that have shaped the symbiosis between the fungus-growing termites and their fungal symbionts and places these changes in an ecological context.