I. S. Darevsky (1924–2009) and rock lizards of the Caucasus: from geographic parthenogenesis to reticulate (hybridogenous) speciation

The path taken by I. S. Darevsky to the discovery of natural parthenogenesis in rock lizards of the Caucasus (1957, 1958) is tracked, as well as his further developments of the problem of parthenogenesis in lizards in his main papers (1962, 1966, 1967) and monograph (1967). The following issues are considered: geographic and hybrid parthenogenesis, subspecies and species in unisexual lizards, spontaneous males in parthenogenetic species, the essence of I. S. Darevsky’s discovery in the context of different categories of clonal reproduction in animals, the formation of the concept of reticular speciation, and the evolutionary age of clonal forms in various groups of animals.