In this innovative textbook, within the framework of the development of the UMC on the course "Phenogenetic analysis of populations" of the master's program "Ecology of nature management" theoretical ideas in the field of studying phenogenetic variability of populations and epigenetic foundations of modern phenotics . are considered. A brief history and methods of population-phenogenetic and phenogenetic studies. Introduced ideas about population ontogeny and population epigenetics. Concepts of the epigenetic landscape of the population and the epigenetic variability generated by it are substantiated. Materials on the variability of hair dryers of non-metric threshold signs and individual phenetic compositions in different groups of invertebrates and vertebrates, as well as a number of model plant species. are considered. Examples of the use of methods of population phenogenetics in the study of problems of intraspecific differentiation, population ecology and solving practical problems of ecosystem biomonitoring are shown .