Before revision:  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:  At the chosen temperature cycling, a prebiotic polymerization chemistry once the strands reach the length to form double stranded species. As shown here, the ligation gave rise to a nonlinear replication process by the cooperative ligation of matching sequences and the emerging increase in sequence length.