Figure 2.

Hyperbolic and parabolic replicators. In (a) we display a simplified scheme of an experimental implementation of a catalytic set of ribozymes forming a cooperative loop. Here each component of the system helps the next to replicate. Dashed lines indicate weaker catalytic links (modified from [37]). The parabolic system outlined in (b) is based on complementary (template) peptide chains involving a ligation mechanism (adapted from [38]).