Frozen Evolution. Or, that’s not the way it is, Mr. Darwin. A Farewell to Selfish Gene.

This possibility would probably be the most interesting from the viewpoint of protobiology, as study of the sequences of contemporary genes could provide information on the functioning of living systems in the initial phases of evolution.It is possible, for example, to imagine that replication of nucleic acids under prebiotic conditions occurred through the combination of oligonucleotides with mutually overlapping complementary sections (Ohno 1987).This would lead to the formation of multiple tandem repetition, with a sequence corresponding to the sequence of modules from which the original chains of nucleic acids were formed (Fig. XI.4).The results to date on the study of gene motifs do not, however, greatly favor this

Fig. XI.4 Replication of nucleic acids by fitting together mutually complementary oligonucleotides. One of the hypotheses explaining the existence of the internal periodicity of modern genes assumes that the periodicity is connected with the original mechanism of DNA replication by fitting together oligonucleotides with mutually complementary sections.

possibility and, to the contrary, there are a number of indirect indications for the second alternative, i.e. for the hypothesis according to which all the genes and their repetitive motifs emerged only after the emergence of the genetic code.