PMID: 107686Jan 1, 1978

The evolution of sexual reproduction as a repair mechanism. Part I. A model for self-repair and its biological implications

Acta Biotheoretica
I Walker


The theory is presented that the sexual process is a repair mechanism which maintains redundancy within the sub-structure of hierarchical, self-reproducing organisms. In order to keep the problems within mathematically tractable limits (see Part II), a simple model is introduced: a wheel with 6 spokes, 3 of them vital and 3 redundant, symbolizes the individual (cell or organism). Random accidents destroy spokes; the wheels replicate at regular cycles and engage periodically in pairing and repair phases during which missing spokes are copy-reproduced along the intact spokes of the partner wheel. The hierarchical structure of such a system is analysed and an 'autonomous unit' is defined: this is the unit of minimal hierarchical complexity which is capable of perpetuating autonomously all higher and all lower levels of the hierarchy; this is the central unit of selection. Four basic, physical parameters are isolated which determine the essential features of any eucaryotic life cycle: 1. The number of levels of the hierarchy (unicellular, multicellular, colonial, etc.); 2. the relation between the phases of replication (asexual generations) and repair (sexual generations); 3. the duration of potential repair (haplo-diplo-phase); 4....Continue Reading


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Related Concepts

Base Excision Repair
Biological Evolution
M Phase, Meiotic
Recombination, Genetic

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