How does a universal genetic code relate to the hypotheses about the origin of life on Earth?

Question

anonymous · Answer

all organisms on Earth have one genetic code (except 
mitochondrias that probably changed it for some reasons).  In fact, 
universal genetic code is fundamental evidence that all organisms 
(viruses, bacterias, eucariotes) evolved from one common ancestor, 
because otherwise organisms should have different genetic codes. 
Furthermore, according to hypothesis of RNA world, all modern organisms 
came from one ancestor that was composed only from nucleic acids. This 
ancestor had RNA as a carrier of genetic information, and used same 
genetic code as now-living organisms.