How viruses shape the tree of life

Abstract

Consideration of virus evolution only from a disease perspective has provided a limited view of virus–host evolution. Such views assume all viruses fit predator/prey models for replication, but fail to explain the origin of disease or how viruses might make significant contributions to host evolution. On a long evolutionary time scale, the ability of a virus to persist in an individual host is a much more prevalent life strategy. Persistence can explain both origins of most viral disease and virus–host evolutionary stability. However, persistence (both genomic and epigenomic) is a much more complex and demanding virus–host relationship that is difficult to study. We must change our attitudes towards persistence if we are to understand how viruses shape the tree of life.