A New Clue to How Life Originated

When Caitlin Cornell looked down her microscope, she saw large bright spots against a black background. They resembled miniature suns, blazing against the backdrop of space. And when Cornell showed the spots to her supervisor, Sarah Keller, a chemist at the University of Washington, “we got really excited,” she recalls. “It was a bit of an ‘Aha!’ moment.” Those spots, she realized, might help address a long-standing puzzle about the origin of life itself.

The cells that make up all living things, despite their endless variations, contain three fundamental elements. There are molecules that encode information and can be copied—. There are proteins—workhorse molecules that. Go back far enough in time, before animals and plants and even bacteria existed, and you’d find that the precursor of all life—what scientists call a “”—likely had this same trinity of parts: RNA and proteins, in a membrane. As the physicist Freeman Dyson once said, “Life began with little bags of garbage.”