Whos cultivating whom?
If fungi play an important role in shaping mound architecture, one must ask why they do this? Fungi are normally enemies of termites, because they are normally parasites on the rich trove of food termites concentrate in their nests. Most termites have evolved defence mechanisms against these parasites, including various kinds of chemical fungistats. A slow-growing fungus like Termitomyces poses little threat, however. Because it absorbs its digestate slowly, Termitomyces leaves ample ‘leavings’ that provide termites a rich food. Indeed, this is one reason why Macrotermes is such a prodigious ‘ecosystem engineer’ – its fungus-enriched food enables it to mobilize energy at faster rates than most termites. However, Termitomyces’ tepid growth also makes it no match for more aggressive fungal competitors, like the common cellulose-digesting fungus Xylaria. Termitomyces seems to use the Macrotermes colony as a sort of safe haven. Although fungus combs are laden with spores of more than two d