In addition to the DNA replication system, epigenetic inheritance system and behavioral transmission system operate to maintain the stability of heritable variations. Epigenetic inheritance systems are responsible for the inheritance of the functional states of genes and cell structure in cell lineage. The epigenetic variations may be random with respect to the environment or they may be induced by the environment. The inheritance of a phenotypic response will be advantageous in a changing environment when the environmental conditions which favour this response last longer than the generation time of the organisms. The induce state can be transmitted to the offspring: both variation in DNA sequence and epigenetic variation can be induced and transmitted, but epigenetic variations are probably more common, because the environment directly modifies the epigenetic system. The properties of the epigenetic inheritance systems and of the behavioural transmission system, and the nature of the periodical fluctuations to which many types of organisms are subjected, determine random and induced heritable phenotypic transition rates. Epigenetic inheritance systems maintain the determined state of cell linkage. This character may explain that the evolution of epigenetic inheritance system in unicellular organisms is important to the evolution of multicellular organisms.
written by 41283226
Lachmann. M., Jablonka. E., (1996). The inheritance of Phenotypes : an Adaptation to Fluctuating Envionmens. Theoretical Biology:181, 1-9
written by 41283226
Lachmann. M., Jablonka. E., (1996). The inheritance of Phenotypes : an Adaptation to Fluctuating Envionmens. Theoretical Biology:181, 1-9
