New Analysis of Iconic Miller-Urey Origin of Life Experiment Asks More Questions Than It Answers | WHAT REALLY HAPPENED X-Frame-Options: SAMEORIGIN

New Analysis of Iconic Miller-Urey Origin of Life Experiment Asks More Questions Than It Answers

How did we get here? It’s no small question. Scientists have been hacking away at the origin of life ever since we opened up “science” in the human skill tree. In 1952, two chemists conducted an experiment designed to brew up a kettle of primordial soup, and in doing so, they began to probe the circumstances under which life arose on Earth. Their work still bears their names: the Miller-Urey experiment inspired countless other studies, and it’s in every freshman biology text. But a new analysis of the OG experiment has concluded that one component of the primordial soup must have come from an unexpected source. The analysis is compelling and peer-reviewed, and it raises more questions than it answers.

The groundbreaking Miller-Urey experiment was designed to test the idea of “abiogenesis,” which is the notion that life could come from that which was not previously living. The idea goes like this: if life came from the primordial soup, and we’re living but the soup wasn’t alive, then at some point there must have been some kind of transition from nonlife to life. Life is made of cells. (Don’t get me started on viruses.) Cells are made of polymers, which are made of monomers, which are made of yet smaller, simpler, building-block molecules. There should be some knowable transition from life to unlife, somewhere in the cosmos we live in, for us to witness and understand.

But the early Earth was very different from the one we occupy, enough so that it confounded our experiments at first. One important difference is the atmosphere: before the Great Oxygenation Event, our planet had a reducing atmosphere, made of things like hydrogen, methane, and ammonia. The difference is so great between our current atmosphere and the primordial atmosphere, in fact, that entirely separate classes of chemical reactions are favored. Still, methane and ammonia contain carbon and nitrogen, which are the necessary raw materials for the backbone of all known proteins and amino acids. Add in gaseous hydrogen and you’ve got the materials to make hydrocarbon chains, sugars, and even nucleic acids. So Stanley Miller and his advisor Harold Urey sealed those gases inside a sterile glass vessel, which was connected to another smaller glass bubble containing water. Heating the water made steam, which mingled with the reducing gases to make a microcosm of what we believed the atmosphere was on the primordial Earth. The resulting clouds swirled around electrodes that sent a spark across a gap, over and over, mimicking lightning from ancient storms. A cooling clamp allowed the vapors to condense into a tiny, domesticated version of the corrosive primordial rain, which puddled in a collection chamber below.