When Miller himself, repeated the experiment
using the correct combo in
1983, the brown broth failed to
materialize. Instead, the mix created a
colorless brew, containing few amino acids. It
seemed to refute a long-cherished icon of
evolution—and creationists quickly seized on it
as supposed evidence of evolution's wobbly
foundations.
However,
Bada's repeat of the experiment—armed
with a new insight—seems likely to turn the
tables once again. Bada
discovered that the reactions were producing
chemicals called nitrites, which
destroy amino acids as quickly as they form.
They were also turning
the water acidic—which
prevents amino acids from forming. Yet primitive Earth would have
contained iron
and carbonate minerals that neutralized nitrites and acids.
So Bada added these chemicals to the
experiment to duplicate these functions. When he
reran the
experiment, he still
got the same watery liquid as Miller did in
1958, but this time it was chuck-full of amino acids. Bada presented his results the last
week of March, 2007 at the American Chemical
Society annual meeting in Chicago.
Christopher
McKay, a planetary scientist at
NASA Ames Research Center in Moffett Field, California
said the repeat experiment is important for it's
a move toward more realism in terms of what the
conditions actually were on early Earth.
Many Origin
of Life researchers believe that the origin of
life depended heavily on chemicals delivered to
Earth in Panspermic-like events by comets and
meteorites. The repeat of Miller's experiments
if viable could shift the paradigm back said
Christopher Chyba, an astrobiologist at Princeton
University. "That would be a terrific result for
understanding the origin of life," he says, "and
for understanding the prospects for life
elsewhere."
Bada's experiment could also have
implications for life on Mars, because the Red
Planet may have been swaddled in nitrogen and
carbon dioxide early in its life. Bada intends to
test this extrapolation by doing experiments with
lower-pressure mixes of those gases.
back2
|