Classification of variability forms based on phenotype determining factors: Traditional views and their revision

Phenotype determining factors are critically analyzed. It is shown that these factors are four: initial hereditary material of an organism, ontogenetic regularities, directional environmental influences, and molecular stochastics. As a result, four separate forms of variability (genotypic, ontogenetic, environmental and fluctuational) are distinguished. Delineation of these phenomena and their place in modern views on variability classification...