Paleovirology

Viral fossils are the subject of an emerging field of evolutionary biology dubbed Paleovirology, the study of ancient viruses. Viral fossil or Paleovirus is an informal term for regions of genomes that originate from ancient germline integration of viral genetic material. The scientific term for such regions is endogenous viral element or EVE. EVEs that originate from the integration of retroviruses are known as endogenous retroviruses, or ERVs, and most viral fossils are ERVs. They may be traced to millions of years back, hence the terminology, although strictly speaking, it is impossible to detect an ancient virus in fossils. The most surprising viral fossils originate from non-retroviral DNA and RNA viruses.