Lessons from Chloroviruses: the Complex and Diverse Roles of Viruses in Food Webs

Viruses can have large effects on the ecological communities in which they occur. Much of this impact comes from the mortality of host cells, which simultaneously alters microbial community composition and causes the release of matter that can be used by other organisms. Viruses can have large effects on the ecological communities in which they occur. Much of this impact comes from the mortality of host cells, which simultaneously alters microbial community composition and causes the release of matter that can be used by other organisms. However, recent studies indicate that viruses may be even more deeply integrated into the functioning of ecological communities than their effect on nutrient cycling suggests. In particular, chloroviruses, which infect chlorella-like green algae that typically occur as endosymbionts, participate in three types of interactions with other species. Chlororviruses (i) can lure ciliates from a distance, using them as a vector; (ii) depend on predators for access to their hosts; and (iii) get consumed as a food source by, at least, a variety of protists. Therefore, chloroviruses both depend on and influence the spatial structures of communities as well as the flows of energy through those communities, driven by predator-prey interactions. The emergence of these interactions are an eco-evolutionary puzzle, given the interdependence of these species and the many costs and benefits that these interactions generate.

Automated summary

Viruses have a significant impact on ecological communities through the mortality of host cells, altering microbial community composition and releasing matter that can benefit other organisms. Recent studies suggest that viruses are more integrated into ecological communities than previously thought, particularly in the case of chloroviruses infecting chlorella-like green algae. These viruses engage in various interactions with other species, luring ciliates, relying on predators for host access, and serving as a food source for protists. These interactions depend on and influence the spatial structures and energy flows of communities, driven by predator-prey relationships. The emergence of these interactions is an eco-evolutionary puzzle with interdependence and various costs and benefits involved.