Wood-eating termites are one of the most numerous and ecologically relevant soil-dwelling insects on earth. They thrive on the abundant biopolymer lignocellulose, depending upon a phy-logenetically diverse community of hindgut microbes including Bacteria, Archaea, and unicellular amitochondriate Eukarya for survival. Bacteriophage, the most abundant virus on the planet, have been isolated from a plethora of different environments, but no one has attempted isolation of phage from termite guts. We hypothesize that bacteriophage have an important ecological role within the termite gut system. Temperate bacteriophage, integrated asprophage into gut bacteria, may have a role in maintaining homeostasis of the termite gut ecosystem by driving evolution of niche specialization, encoding toxin-producing genes, and providing "immunity” for their bacterial hosts against lysis by exogenous bacteriophage.