Asteroid Impacts Could Benefit Underground Life
An incoming asteroid may benefit microbes living deep underground, according to a recent study of an ancient impact in the United States’ Chesapeake Bay. A biological census of the subsurface life forms suggests that impacts create new niches for these deep dwellers to spread into.
In the last couple of decades, biologists have come to realize that the biosphere doesn’t stop at the surface. A large fraction of the Earth’s biomass is lurking down below. Several drilling projects have brought up evidence of hearty little microbes thriving in deep rock sediments. Some eat organic scraps that seep down from our world, while others derive energy through chemical reactions with iron and sulfur. Although it’s hardly paradise, this netherworld has one thing going for it: it’s fairly peaceful. There’s no night or day, no winter or summer. No global warming or ice ages to worry about. Only the occasional earthquake or asteroid impact is really going to shake things up.