The Spark of Life: Darwin and the Primeval Soup by Christopher Wills and Jeffrey Bada, Perseus, $27, 291 pages.

The Chapel Hill News


October 7, 2001

Chemistry of creation

Where did we come from? is a question that virtually every culture has tried to answer, from the Babylonian "Enuma elish" to the Bible's "Genesis." More than 2,000 years ago, Aristotle proposed the first secular theory of creation, called "spontaneous generation." He said that living organisms are regularly created from nonliving matter. Frogs came from river mud, worms from grassy sod, and so forth. Although skeptics questioned this theory, a better idea did not come along until 1924, when a Russian biochemist, Aleksandr Oparin, authored a small book containing a remarkable concept known as "chemical evolution."

Oparin speculated that simple organic compounds, such as amino acids, formed in the early Earth's oceans, creating a primordial soup rich in the materials found in living organisms. (Amino acids are the building blocks of proteins, which are the workhorses of all cells.) These compounds, he reasoned, would then interact with one another and form even more complex aggregates, which could somehow replicate themselves, at least approximately. At this point evolution would kick in. The molecules that replicated rapidly would persist, and either a cellular-like metabolism or genes would develop, creating our planet's first primitive cell, from which all life descended.

Since Oparin's book appeared, scientists have taken long strides toward proving this theory - although no one has yet created life in a test tube. In their book "The Spark of Life: Darwin and the Primeval Soup" (Perseus, $27), California professors Christopher Wills and Jeffrey Bada recount the history and status of scientists' attempts to create a living organism from nonliving matter. Their book reminded me of another book written by John Horgan a few years ago titled "The End of Science." Horgan made the case that the great era of scientific discoveries is over, that what we don't already know may be unknowable.

For example, what happened at the exact moment of the Big Bang? Are subatomic particles actually composed of strings vibrating in 10 dimensions? How did life on Earth begin? Scientists all over the world are working on these and other fundamental questions, but until someone succeeds in answering one, it is not possible to refute Horgan's thesis. Although progress is being made on all fronts, I suspect that science's concentrated attack on the origin of life holds the best promise of proving that science -- truly fundamental and important science -- has not ended.

The first test of Oparin's ideas was the famous Miller-Urey experiment. In 1952, Stanley Miller was a graduate student in the chemistry department at the University of Chicago. After attending a lecture by Nobel laureate Harold Urey on the conditions that existed on Earth soon after it formed. Miller decided to re-create those conditions in the lab. He proceeded to make a world of glass. Water in one flask was the "ocean." Glass tubing connected it to the "atmosphere" in another flask, which contained a mixture of three simple chemicals that were assumed to be present in the Earth's early atmosphere -- methane, ammonia and hydrogen. Electrodes generated sparks that simulated lightning strikes. After a week of boiling, the pure water in the "ocean" had turned yellow-brown and was coated with an oily scum. Analysis showed that the water contained glycine and other amino acids, the constituents of proteins. Miller did not create life in his flask, but he did create the building blocks of life.

Time and Life magazines and many newspapers heralded Miller's achievement with headlines such as "Test Backs Theory That Life Began as Chemical Act." But, of course, all he had done was synthesize a few amino acids. Miller and other scientists knew that they were a long way from creating life. Still, it was a start, a jumping off point for the research that was to follow. Since then, scientists have demonstrated that nonliving molecules can indeed evolve, just as Oparin theorized in 1924. And the search is on to find the precursor of a living cell, a molecule that could self-replicate in the primordial soup. This work has been unsuccessful so far, but Wills and Bada maintain that "life is not an unlikely accident." "It is hard to imagine," they write, "that life has not appeared in many other parts of the universe. Soon, it will appear in a test tube. And the world will never be same."

If they are right, then John Horgan will join a long list of people who have wrongly predicted the end of science. In 1894, for example, an eminent physicist said that "it seems probable that most of the grand underlying principles have been firmly established." Eleven years later, Albert Einstein overturned of those firmly established principles when he published his theory of relativity.

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