urey miller experiment does not prove life arises from primordial earth, it simply proved that building blocks of life may be produced in the primordial earth...
there's still a huge debate on where does life on earth originate from.
i piece of evidence, iirc, is that mitochondria carries a different set of genetic information in a lot of eukaryotic cells, indicating that primitive prokaryotic cells engulfs an other prokaryotic cells (heterotrophic nature) and in turn the engulfed cell becomes a separate organelle.