Hello dear friends!
Many molecules of life are found enantiopure in organisms. From time to time, a paper or article wants this to result from some minimally unsymmetrical physics law, for instance the weak interaction influencing chemical reactions. Though, I don't see why anything more than chance should be the reason.
On Earth, present or past life (in fossil fuels, limestone...) hoards the components of life, notably carbon, so much that we call "organic" the compounds of carbon. In CO2, carbon is available to both forms. So if at some point "left" and "right" organisms and molecules coexist(ed) on the planet, they would compete for the available carbon and other components.
Considering also that life reproduces itself enantiopure, including from one species to an other as they pass the same amino-acids and so on during a mutation, I believe that one enantiomer has to win over the other.
So life left- or righthanded on Earth would only result from which enantiomers appeared first. The other could have won just as well.
Comments, dissent, additions, corrections please?
Marc Schaefer, aka Enthalpy