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LIFE IS NOT
A MIRACLE
HAROLD UREY (1893–1981)
STANLEY MILLER (1930–2007)
IN CONTEXT
BRANCH
ChemistryBEFORE
1871 Charles Darwin suggests
that life might have begun in
“some warm little pond.”1922 Russian biochemist
Alexander Oparin proposes
that complex compounds
might have formed in a
primitive atmosphere.1952 In the US, Kenneth A.
Wilde passes 600-volt sparks
through a mixture of carbon
dioxide and water vapor, and
obtains carbon monoxide.AFTER
1961 Spanish biochemist
Joan Oró adds further likely
chemicals to the Urey–Miller
mix and obtains molecules
vital for DNA, among others.2008 Miller’s former student
Jeffrey Bada and others use
newer, more sensitve
techniques to obtain many
more organic molecules.S
cientists have long pondered
the origin of life. In 1871,
Charles Darwin wrote in a
letter to his friend Joseph Hooker,
“But if...we could conceive in
some warm little pond, with all
sorts of ammonia and phosphoric
salts, lights, heat, electricity etc
present, that a protein compound
was chemically formed ready to
undergo still more complex
changes...” In 1953, American
chemist Harold Urey and his
student Stanley Miller found a
way to replicate Earth’s early
atmosphere in the laboratory, and
generated from inorganic matter
organic (carbon-based) compounds
that are essential to life.
Before the Urey–Miller
experiment, advances in chemistry
and astronomy had analyzed the
atmospheres on the other, lifeless
planets in the solar system. In the
1920s, Soviet biochemist Alexander
Oparin and British geneticist J. B. S.
Haldane independently suggested
that if conditions on prebiotic
(prelife) Earth resembled those
planets, then simple chemicals
could have reacted together in
a primordial soup to form more
complex molecules, from which
living things might have evolved.More complex molecules
might have been formed,
providing the building
blocks of the earliest
life forms.Earth’s early atmosphere
contained a mixture
of gases.Given enough energy,
those gases might have
reacted together.Life is not a miracle.