 Dyson proposed that in a primitive early cell containing ATP and AMP, RNA and replication came into existence only because of the similarity between AMP and RNA.He suggested that AMP was produced when ATP molecules lost two of their phosphate radicals, and then one cell somewhere performed Eigen's experiment and produced RNA.There is no direct evidence for the dual origin theory, because once genes developed, they took over, obliterating all traces of the earlier forms of life.