A 2011 paper in the research journal Nature Reviews Microbiology calculated there were approximately ten nonillion viruses on earth — that’s 1 x 1031 or a number with 1 followed by 31 zeros.
Despite the bad rap they get, not all viruses are bad for us.
Roberts says the human race couldn’t survive without some of them, like those found in our guts which help to keep our digestive systems in balance.
“Viruses,” he says, “are the oil that lubricates the gears of evolution.”
