There is still a debate about whether or not viruses are a form of life. We really don’t know where they came from; they are so tiny that none have been preserved in rocks so there is no fossil record to study. When viruses have infected organisms, however, they have ended up being preserved in other organisms. That has enabled researchers to learn a bit more about them.
It seems that they have been around as long as life has been on Earth. Some researchers have suggested that they were among the first organisms ever. Scientists in the field of paleovirology are trying to reveal more about the evolution and history of viruses. In this video, you can learn more about the theories about their origins, and the research methods that will help show which one is correct.
You can also hear more about how viruses have contributed to the evolution of other species as well, including us. It is estimated that eight percent of the human genome traces back to viruses.