Viruses can infect all forms of life:  bacteria, archaea, and eukaryotes. And because of their simplicity, which is their key to survival, researchers think they evolved alongside, or even before, the earliest cells. But there’s no fossil record of viruses in the conventional sense. How do we know where they came from?

THIS IS COOL. I WANT TO LEARN SOMETHING ELSE, TOO!

Video via – PBS Eons
Further Readings And References @ Journal of Virology, BioMed Central [1][2], Nat Rev Microbiol