9.13: Viral Ecology Last updated Jan 3, 2021 Save as PDF 9.12C: RNA Oncogenic Viruses 9.13A: Emergence of Viral Pathogens Page ID9932 BoundlessBoundless ( \newcommand{\kernel}{\mathrm{null}\,}\) Topic hierarchy9.13A: Emergence of Viral PathogensMany viruses that were once benign later become pathogens through genetic change, which can occur by several mechanisms.9.13B: Viral Roles in EcosystemsViruses are immensley important to the turnover of biomass in many ecosystems.