Genetics and metabolism of ambrosia fungi
Interactions between ambrosia beetles and ambrosia fungi are one of the most intriguing aspects of the symbiosis, but definitely the least known. Even the basic patterns in composition and dynamics of the symbiotic consortium are unclear. According to a traditional view, ambrosia beetles mechanistically inoculate their galleries with clonal monocultures of a favored fungus species (Francke-Grosmann, 1967; Mueller et al., 2005). Alternative observations suggest that beetles may maintain a stable community of symbiotic fungi (Kuhnholz, 2004), or that the beetles can coexist with and develop on a number of interchangeable fungi recruited from the environment (Batra, 1966). This variety of views betrays the paucity of comparable data and limited spatial and taxonomic scope of many experiments.
It’s not even known, if it’s the beetles who somehow choose the right fungus among the myriads of opportunistic fungi in decaying wood, or it’s the fungi that assure their own transmission by outcompeting other fungi in mycangia and in the wood, or some other factors.
Batra, L.R. (1966) Ambrosia fungi: extent of specificity to ambrosia beetles. Science, 153, 193-195.
Francke-Grosmann, H. (1967). Ectosymbiosis in Wood-Inhabiting Insects. In Symbiosis (ed. by S.M. Henry), Vol. 2 – Associations of Invertebrates, Birds, Ruminants and Other Biota, pp. 141-206. Academic Press, New York.
Kuhnholz, S. (2004) Chemical ecology and mechanisms of reproductive isolation in ambrosia beetles, Simon Frazer University, Burnaby.
Mueller, U.G., Gerardo, N.M., Aanen, D.K., Six, D.L., & Schultz, T.R. (2005) The evolution of agriculture in insects. Annual Review of Ecology and Systematics, 36, 563-595.