Scripps professor of marine chemistry Jeff Bada produces an electrical stark in an experimental apparatus to show how the atmospheric conditions during volcanic eruptions may have led to early life on Earth. (Credit: Scripps Institution of Oceanography, UC San Diego)
New research suggests that lightening and volcanoes may have sparked early life on Earth. Researcher Jeffrey Bada at Scripps Institution of Oceanography at UC San Diego and colleagues reanalyzed Stanley Miller's classic origin of life experiment, offering a new analysis on how the essential building blocks of life may have arisen from volcanic eruptions.
Bada, Scripps professor of marine chemistry and graduate student of Miller's in the Chemistry Department at the UC San Diego in 1960, preserved Miller's original chemical samples. Bada along with lead author Adam Johnson, Indiana University graduate student and colleagues, reanalyzed the samples to determine if new chemical compounds could be detecting using modern equipment. The paper, "The Miller Volcanic Spark Experiment," is published in the Oct. 17 issue of the journal Science.
"We believed there was more to be learned from Miller's original experiment," said Bada, co-author in the paper. "We found that a modern day version of the volcanic apparatus produces a wider variety of compounds."
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 in vapor-rich volcanic eruptions. The experiment circulated methane, ammonia, water vapor and hydrogen in a closed experiment, 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 was comprised of many small volcanic islands. This study suggests 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's lab is the first to perform follow up studies using Miller's original apparatus and chemicals samples, which were discovered following Miller's death in 2007. Researchers reanalyzed 11 of the original samples using contemporary analytical chemistry techniques and produced 22 amino acids, the building blocks of proteins, 10 of which had not been identified previously by Miller.
"Historically, you don't get many experiments that might be more famous than these; 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," said lead author Adam Johnson, a Indiana University graduate student with the NASA Astrobiology Institute team.