Volcanoes May Be Original Womb of Life

Clara Moskowitz, LiveScience Staff Writer, 10/2008

Fifty years ago, a chemist named Stanley Miller 

conducted a famous experiment to investigate how life

could have started on Earth.

Recently, scientists re-analyzed his results using modern 

technology and found a new implication: The original

sparks for life on our planet could have come from

volcanic eruptions. 

The 1950s experiment was designed to test how the

ingredients necessary for life could arise.

Miller and his University of Chicago mentor Harold Urey

used a system of closed flasks containing water and a

gas of simple molecules thought to be common in Earth's

early atmosphere. They zapped the gas with an electric

spark (representing lightning on ancient Earth), and found

that after a couple of weeks the water turned brown. It

turned out that amino acids, the complex molecules that

make up proteins, had formed from the simple materials in

the flasks.

The finding was lauded as proof that the fundamental

building blocks of life could be derived from natural

processes on our planet.

Recently, Scripps Institution of Oceanography researcher

Jeffrey Bada, who was Miller's graduate student when the

experiment was first performed, stumbled upon vials

containing residues from the tests. In a slight variation on

the famous experiment, in some of these trials, steam had

been injected into the gas to simulate conditions in the

cloud of an erupting volcano. These results had never

been made public.

In the newly recovered samples, Bada and his team found

22 amino acids, 10 of which had never been found in any

other experiment like this.

"The apparatus Stanley Miller paid the least attention to

gave the most exciting results," said team member Adam

Johnson, a graduate student at Indiana University. "We

suspect part of the reason for this was that he did not

have the analytical tools we have today, so he would

have missed a lot."

And, after re-analyzing the samples from the original trials

that had been published in 1953, the team also found that 

those flasks contained far more organic molecules than

Stanley Miller realized. 

"We believed there was more to be learned from Miller's

original experiment," Bada said. "We found that in

comparison to his design everyone is familiar with from

textbooks, the volcanic apparatus produces a wider

variety of compounds."

The researchers published the results of their new

analysis in the Oct. 16 issue of the journal Science. Over

the past 50 years, scientists have changed their thinking

about what elements were present in the atmosphere of

early Earth. Miller used methane, hydrogen and ammonia

in his experiments, though now researchers think Earth's

ancient atmosphere was mostly carbon dioxide, carbon

monoxide and nitrogen.

"At first glance, if Earth's early atmosphere had little of

the molecules used in Miller's classic experiment, it

becomes difficult to see how life could begin using a

similar process," said team member Daniel Glavin of

NASA's Goddard Space Flight Center in Greenbelt, Md.

"However, in addition to water and carbon dioxide,

volcanic eruptions also release hydrogen and methane

gases. Volcanic clouds are also filled with lightning, since

collisions between volcanic ash and ice particles

generate electric charge. Since the young Earth was still

hot from its formation, volcanoes were probably quite

common then."

·           101 Amazing Earth Facts 

·           Top 10 Questions About Earth 

·           Greatest Mysteries: How Did Life Arise on Earth? 

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