The animal domestication experiment as a model of the evolutionary process: A new insight into evolution under selection targeting regulatory systems

Abstract

The paper considers the main results of the long-lasting experimental domestication of animals-foxes, minks and brown rats. The following important conclusions have been made. Fundamental to the domestication process is the intensive selection of animals for human-tolerant behavior and the capability to adapt to the emerging social structure “human-domestication object”. Intensive selection for behavior and, therefore, for the central regulatory systems, which control the functioning of the entire organism, leads to large amounts of variability in the population under domestication. Stress caused by rapid environmental changes, with its neurohormonal mechanisms of regulation of genetic processes, has an important role in the induction of variability. These considerations prompted Dmitry Belyaev, mutational variability is rendered neutral. Under directional (and destabilizing) selection, hidden mutational variability becomes exposed. If the regulatory circuits with negative feedback are lost, hidden genotypic variability becomes exposed and individuals with major phenotypic aberrations occur.