EVEN the earliest forms of cellular life may have been plagued by viruses.
All viruses, including a newly discovered one that is unlike any other seen before, share a common design principle. This suggests these modern viruses also share a common ancestor that appeared before different viruses evolved to infect the three main domains of life: bacteria, archaea and eukaryotes, which themselves began separating at least 3 billion years ago. “Viruses are as old as life itself, if not older,” says Mark Young, a virologist at Montana State University in Bozeman.
Young and his colleagues reached this conclusion by studying…
