Before revision:  Here, we demonstrate the spontaneous emergence of higher-order cooperative replication from a network of simple ligationchain reactions (LCR). We performed long-term LCR experiments from a mixture of sequences under molecule degrading conditions with a ligase protein. At the chosen temperature cycling, a network of positive feedback loops arose from both the cooperative ligation of matching sequences and the emerging increase in sequence length.
After revision:  Here, we demonstrate with experimental and theoretical findings that templated ligation would provide such a self-selection. In templated ligation, two adjacent single sequences strands are chemically joined when a third complementary strand sequence brought them in close proximity. This simple mechanism was a likely side-product of a network of positive feedback loops arose from both the cooperative ligation of matching sequences and the emerging increase in sequence length.