September 22, 2010
Scientists don’t yet know how life began here on Earth. Mineralogist Bob Hazen, who is profiled in the October issue of Smithsonian, thinks that rocks were key to the development of life. Reporter Helen Fields wrote:
It’s the complexity of the hydrothermal vent environment—gushing hot water mixing with cold water near rocks, and ore deposits providing hard surfaces where newly formed amino acids could congregate—that makes it such a good candidate as a cradle of life. “Organic chemists have long used test tubes,” he says, “but the origin of life uses rocks, it uses water, it uses atmosphere. Once life gets a foothold, the fact that the environment is so variable is what drives evolution.”
But long before Hazen started his research into the origins of life, scientists thought that life might have begun in some “warm little pond,” as described by Charles Darwin. Helen explained in her story:
In 1952, Stanley Miller, a graduate student in chemistry at the University of Chicago, attempted to create Darwin’s dream. Miller set up a container holding water (representing the early ocean) connected by glass tubes to one containing ammonia, methane and hydrogen—a mixture scientists of the day thought approximated the early atmosphere. A flame heated the water, sending vapor upward. In the atmosphere flask, electric sparks simulated lightning. The experiment was such a long shot that Miller’s adviser, Harold Urey, thought it a waste of time. But over the next few days, the water turned deep red. Miller had created a broth of amino acids.
The National Air and Space Museum in its The Universe gallery used to show a video of Julia Child recreating Stanley Miller’s famous experiment, cooking up Primordial Soup. (The gallery is long closed, but Julia’s video can still be seen at the Smithsonian’s National Museum of American History, where it plays sometimes on screens near her famous kitchen.) But “soup” probably was the wrong word for whatever existed when life began. Helen wrote:
“We’ve got a prebiotic ocean and down in the ocean floor, you’ve got rocks,” he says. “And basically there’s molecules here that are floating around in solution, but it’s a very dilute soup.” For a newly formed amino acid in the early ocean, it must have been a lonely life indeed. The familiar phrase “primordial soup” sounds rich and thick, but it was no beef stew. It was probably just a few molecules here and there in a vast ocean. “So the chances of a molecule over here bumping into this one, and then actually a chemical reaction going on to form some kind of larger structure, is just infinitesimally small,” Hazen continues.
I guess Primordial Weak Tea just doesn’t have the same ring to it.
Sign up for our free email newsletter and receive the best stories from Smithsonian.com each week.