Hypercycle selection

Strongly than linearly on the concentration of the growing entity (as is the case for hypercycles), selection may become of an entirely different, non-Darwinian nature than is normal for a quasi-species [4]. 

As expected, a response to the hypercycle criticisms appeared, in fact in the same issue of the Journal of Theoretical Biology (Eigen et al., 1980). According to this, the Freiburg investigations refer to one particular evolution model, in which the occurrence of mutants with different, selective values is ignored. In such realistic models, the error threshold loses its importance for the stability of the wild type. If the latter reaches a finite fitness value, it can always be the subject of selection, as no rivals are present. 

Here the switching occurs as in phase 3. With the pressure for selection of the protocells, cells with a new (quasi-)recursive state are selected that consist of molecules with higher catalytic activities (i.e., with larger indices of species). Again each recursive state consists of IHN, and the species with the highest catalytic activity in the core hypercycle is minority in population. Once the population of such species is decreased by fluctuations, there occurs a switch to... 

The detailed mathematical analysis of equation (18) has been given previously (Schuster et al., 1978 Eigen and Schuster, 1979 Schuster et al., 1979). A general proof was presented that the elements of equation (18) co-operate no selection occurs. The dynamics of higher dimensional elementary hypercycles (n 5) is of a certain interest. The individual concentrations oscillate in regular manner, contro-led by a stable limit cycle. 

Computer modeling of hypercycles (Kiippers, 1975 Eigen and Schuster, 1977, 1978) demonstrates the development of oscillatory behavior around a steady state which, through feedback and coupling of the members of the hypercycle, minimizes the effect of mistakes in reproduction and thus allows for selection and optimization of the dynamic structures. So viewed, hypercycles represent the minimum structural organization for a system to accumulate, maintain, and process the information in the genome. 

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