Artificial life and molecular evolutionary biology

Abstract

Artificial life is extending the scope of molecular evolutionary biology as it tries to complement natural life on earth by searching for systems with properties that are sufficient to allow for evolution. Evolution is characterized by specific forms of dynamics that are based on the capability of replication. RNA molecules form a toy universe calles the RNA world that shares many features with current scenarios of procaryotic life. Since RNA is able to unite the properties of genotypes (sequences) and phenotypes (spatial structures) within the same molecule, RNA sequence to structure mappings present the key to an understanding of evolutionary dynamics. Such mappings dealing with RNA secondary structures allow straightforward investigations assisted by computer simulation and mathematical analysis. The main result of these studies is summarized in the principle of shape space covering: Only a small fraction of sequence space has to be searched in order to find a sequence that folds into a predefined structure.