Sparks of Life

A research team that included Jeffrey Bada, a professor of marine chemistry at Scripps Institution of Oceanography at UC San Diego, has reanalyzed the classic origin of life experiment of Bada’s former mentor and produced a new analysis on how the essential building blocks of life may have arisen from lightning and volcanic eruptions.

Famed chemist Stanley Miller’s classic “primordial soup” experiment, published in Science in 1953, is still widely used today in high school chemistry labs to mimic chemical reactions that occur during vapor-rich volcanic eruptions. The experiment circulated methane, ammonia, water vapor, and hydrogen in a closed chamber, simulating the earth’s early atmosphere and sent a lightning-like spark through it.  Over a series of days, organic compounds formed in the mixture, demonstrating how Earth’s primitive atmosphere may have given rise to life.

It is commonly thought that early Earth contained many small volcanic islands. This study, by Adam Johnson, an Indiana University graduate student, bolsters the assertion that lightning and the release of gases associated with these volcanic eruptions could have produced the necessary chemical components to give rise to early life.

Bada and Johnson performed follow-up studies using Miller’s original apparatus and chemical samples, which were discovered following Miller’s death in 2007. The team wanted to see if modern equipment could discover chemicals that could not be detected with the techniques of the 1950s. The scientists reanalyzed 11 of the original samples using contemporary analytical chemistry techniques. In the process, they produced 22 amino acids, the building blocks of proteins, 10 of which had not been identified previously by Miller, who joined the Chemistry Department at UCSD in 1960.

“We believed there was more to be learned from Miller’s original experiment,” said Bada, who was Miller’s graduate student between 1965 and 1968 prior to joining the Scripps faculty in 1971.  “We found that a modern-day version of the volcanic apparatus produces a wider variety of compounds that could have given rise to early life.”

The journal Science published the results of a paper co-authored by Bada detailing the new analysis, “The Miller Volcanic Spark Experiment,” in its Oct. 17 issue.

“Historically, you don’t get many experiments that might be more famous than these,” added Johnson. “They redefined our thoughts on the origin of life and showed unequivocally that the fundamental building blocks of life could be derived from natural processes.”

-- Annie Reisewitz