Retroviruses ‘almost half a billion years old’

Retroviruses — the family of viruses that includes HIV — are almost half a billion years old, according to new research. That’s several hundred million years older than previously thought and suggests retroviruses have ancient marine origins, having been with their animal hosts through the evolutionary transition from sea to land. The findings will help us understand more about the continuing ‘arms race’ between viruses and their hosts.
Paleontology News — ScienceDaily