Facilitated variation

The theory of facilitated variation ( engl: Theory of Facilitated Variation) is an explanatory model that is designed to complement the theory of evolution, which focuses on the nature of variation in evolution. This theory was founded in 2005 by Marc Kirschner, founder and chairman of the Department of Systems Biology at Harvard Medical School, and John Gerhart, a professor at the University of California, Berkeley, in her book "The Plausibility of Life" published ( German title: Die solution of Darwin's dilemma ).

Summary

First start from the observation that not all subject in the course of evolution the change, but there are a number " conserved core processes " ( conserved core processes ) are such as the basic information processing of DNA, RNA and protein synthesis. Furthermore, the molecular biological processes are considered relevant for the function of the phenotypic the genotypic variation. Three aspects are highlighted, which facilitate evolvability and the emergence of the new:

• Weak regulatory coupling ( weak regulatory linkage ): This is a form of regulation that can be easily developed and modified to couple the conserved core processes in other compilation together. The regulatory signal provides this limited information, the receiver is itself " maximum information ", ie the signal simply selects one of the receiver provided answers. This is also referred to as permissive interaction.
• Exploratory behavior or exploratory behavior ( exploratory behavior ): It is adaptive behavior of certain cellular and developmental physiology core processes that roughly operate on the principle of " trial and error " and can generate a large number of specific states in this manner, each of which by physiological interactions can be selectively stabilized. An example of this are microtubules, which make contact with the chromosomes during mitosis.
• Compartmentalization: The formation of the body blueprint in animals begins with the phylotypic stage during embryonic development, during which they are spatially defined expression of Selektorgenen and in consequence of the secretion of signaling proteins for the first time. These "invisible anatomy " itself is preserved for each strain of animal, but due in connection with the weak regulatory coupling independent reaction chambers in the body and thus, a high adaptability of the visible anatomy.