This is probably going to come as a shock, which may strike you as kind of funny in a moment, but “soup had its greatest moment in 1953.” That claim, outrageous to anyone who has recently enjoyed a really great bowl of bean-with-bacon, comes from British science journalist Adam Rutherford in his new book Creation: How Science Is Reinventing Life Itself.
A closer read, however, reveals that Rutherford is referring to the so-called prebiotic soup, a phrase coined by another eminent Englishman, evolutionary biologist J.B.S. Haldane, to describe the idea of a pond rich enough in chemical ingredients to allow the spontaneous formation of the first living cell.
American chemist Stanley Miller reached the aforementioned pinnacle of soup in 1953 when he combined water, methane, hydrogen and ammonia, which he assumed were the primary constituents of the atmosphere some four billion years ago, and zapped it with electricity to emulate lightning. (I told you “shock” would be retroactively funny.) Within days the mixture darkened. Miller's analysis revealed the presence of amino acids, top-notch prebiotic material.
This seemingly obvious proof of concept for how the early Earth got lousy with biochemistry became so famous that it was later featured in the final episode of Star Trek: The Next Generation. The omnipotent being known as Q drags our hero Captain Picard to Earth some 3.5 billion years ago, notes some bubbling slime and says, “This is you. I'm serious. Right here, life is about to form on this planet for the very first time. A group of amino acids are [sic] about to combine to form the first protein, the building blocks of what you call life ... everything you know, your entire civilization—it all begins right here in this little pond of goo.” The scene is worth watching just to witness actor John de Lancie's attempt to turn “goo” into a three-syllable word.
The problem with the bisque-beginning-of-life concept is that it's almost certainly wrong. Prebiotic soup, Rutherford told me by phone from across the big pond, “was this incredible idea that complexity, in terms of biomolecules, can spontaneously emerge if the conditions are right. It is iconic, and it's an important experiment. But it's also been a great contributor to what I argue is the incorrect version of how life started on this planet.”
The amino acids generated in a Miller-style primordial ooze just lie there, not doing the backstroke. “Once those chemicals have reacted,” Rutherford says, “they will stop reacting. That's the end of that process. And that's the one fundamental thing that life doesn't do. Life is a continual chemical reaction.” You could wait forever and still not get a fly in your soup.
Researchers more recently have identified places that better fit the bill for bringing about the birds and bees: deep-sea hydrothermal vents called white smokers. But a white smoker's heat, like Stan's electricity, only does so much to a given pot of soup. The smokers also bring up lots of hydrogen, however, and force cell-size pores into the surrounding molten rock. Strip away an electron from one of the hydrogen atoms spewing from these vents, and you're left with a lonely proton. And a proton imbalance on either side of one of these pores necessarily leads to a flow of charged particles that just maybe gets enough chemistry going—and keeps it going—to lead to us pondering torpid ponds today.
“Life is like a casino,” Rutherford says, and not because they're good places to find white smokers, in this case coughing up their retirement savings. “Everyone knows that in the long run the house always wins. But what life is is a kind of continual breaking even against the house. And it's been continual for about four billion years. When you die, you get kicked out, and the energy contained within your cells gets returned to the house. But during your life you extract energy from the environment and hang onto it. It's sort of like sitting at the blackjack table and managing to stay there for the whole night.” Before you leave, don't forget to catch the show.
This article was originally published with the title Bouillabaisse Biology.