Simulation as a tool to identify dynamical typology of water frog hemiclonal population systems

Abstract

Some related species give rise to interspecies hybrids with hemiclonal inheritance. The gametes of such hybrids transfer the set of hereditary information of one of the parental species. The water frog, Pelophylax esculentus, is an example of such hybrids. The hemiclonal hybrids together with their parental species form a biosystem for which the suggested name is Hemiclonal Population System (HPS). The phenomenon of interspecific hemiclonal reproduction of water frogs has been intensively explored for several decades, but insufficient study has been devoted to the mechanisms of the composition constancy and ecological stability of their population systems. In this paper we focus on sustainability and possible results of transformations (in terms of different genetic forms and of population dynamics of each of these forms) of HPSs that consist of diploid representatives. By means of a simulation model we evaluated the long-term consequences of parameters that were derived from empirical research on a natural HPS at a particular brief time-period. This research was carried out in the region of eastern Ukraine, the so-called Siverskyi Donets center of diversity of the Pelophylax esculentus complex. Our study describes the development of a dynamic typology of the HPS by principal component analysis of data generated by the simulations. We investigate the space of the possible states of the HPS. The simulations helped to split this state-space into six areas of stability, each of which corresponds to a different type of stability. Before conducting the simulation study we assumed there were only four truly stable states. Two new states were identified as a result of using this model.