New York Times: "Trillions Upon Trillions of Viruses Fall From the Sky Each Day", amirite?
Generally it’s assumed these viruses originate on the planet and are swept upward, but some researchers theorize that viruses actually may originate in the atmosphere. (There is a small group of researchers who believe viruses may even have come here from outer space, an idea known as panspermia.)
Whatever the case, viruses are the most abundant entities on the planet by far. While Dr. Suttle’s team found hundreds of millions of viruses in a square meter, they counted tens of millions of bacteria in the same space.
Mostly thought of as infectious agents, viruses are much more than that. It’s hard to overstate the central role that viruses play in the world: They’re essential to everything from our immune system to our gut microbiome, to the ecosystems on land and sea, to climate regulation and the evolution of all species. Viruses contain a vast diverse array of unknown genes — and spread them to other species.
Last year, three experts called for a new initiative to better understand viral ecology, especially as the planet changes. “Viruses modulate the function and evolution of all living things,” wrote Matthew B. Sullivan of Ohio State, Joshua Weitz of Georgia Tech, and Steven W. Wilhelm of the University of Tennessee. “But to what extent remains a mystery.”