Apr. 21, 2010 Scientists are reporting discovery of what may be
the "ancestral Eve" crystal that billions of years ago gave life
on Earth its curious and exclusive preference for so-called
left-handed amino acids. Those building blocks of proteins come
in two forms -- left- and right-handed -- that mirror each other
like a pair of hands. Their study, which may help resolve one of
the most perplexing mysteries about the origin of life, is in
ACS' Crystal Growth & Design, a bi-monthly journal. Tu Lee and
Yu Kun Lin point out that conditions on the primordial Earth
held an equal chance of forming the same amounts of left-handed
and right-handed amino acids. Nevertheless, when the first forms
of life emerged more than 3 billion years ago, all the amino
acids in the proteins had the left-handed configuration. That
pattern continued right up to modern plants and animals. The
scientists used mixtures of both left- and right-handed aspartic
acid (an amino acid) in laboratory experiments to see how
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