A couple weeks ago I wrote about the 98,000 viruses that have permanently pasted their genes into our genome over the past 60 million years. What makes these viruses doubly fascinating is that scientists are making new discoveries about them all the time. Over at the open-access journal PLOS Pathogens, two new papers add some pieces to the puzzle of how these viruses get into our genomes, and how they affect our health along the way.

The first paper offers a striking portrait of a virus hopping species. Researchers at the Cleveland Clinic stumbled across the virus as they were studying prostate cancer that runs in families.

It turns out that some forms of prostate cancer are associated with mutations