The building blocks of life may be more than merely common in the cosmos.
Humans and aliens could share a common genetic foundation.
That’s the tantalizing implication of a pattern found in the formation of
amino acids in meteorites, deep-sea hydrothermal vents, and simulations of
primordial Earth. The pattern appears to follow basic thermodynamic laws,
applicable throughout the known universe.
“This may implicate a universal structure of the first genetic codes
anywhere,” said astrophysicist Ralph Pudritz of McMaster University in Hamilton,
There are exactly 20 standard amino acids complex molecules that combine to
form proteins, which carry out instructions specified by RNA and DNA, its
double-stranded and self-replicating descendant.
Ten were synthesized in the famous 1953 Miller-Urey experiments, which
modeled conditions believed to exist in Earth’s early atmosphere and volcano-heated pools. Those 10 amino acids have
also been found in meteorites, prompting debate over their role in sparking life
on Earth and, perhaps, elsewhere.
Pudritz’s analysis, co-authored with McMaster University biophysicist
Paul Higgs and published Monday onarXiv, doesn’t settle the former debate, but it does suggest that basic amino
acids are even more common than thought, requiring little more than a relatively
warm meteorite of sufficient size to form. And that’s just the start.
If the observed patterns of amino acid formation simple acids require
low levels of energy to coalesce, and complex acids need more energy indeed
follow thermodynamic laws, then the basic narrative of life’s emergence could be