Professor Zaleśny and taxonomy

Modern research on the taxonomy and phylogeny of parasitic worms uses a so-called 'integrative approach', based on the use of morphological and molecular data. However, single molecular markers (mitochondrial or nuclear) are most commonly used, which should back up morphological data.

– A lack of correspondence between the morphological data and the results of molecular analyses is unfortunately very often observed, causing frustration among taxonomists – says Prof. Zaleśny.

The main objective of his research project is to optimise and implement genotyping by sequencing (GBS) techniques to study the taxonomy and host specificity of digenetic flukes. The model that will be used in the project consists of flukes of the genus Cotylurus, which are a relatively small group of highly specialised, widespread flukes, specific parasites of the digestive tract and the bursa of Fabricius of wetland birds. Adult forms of Cotylurus have significant morphological variability, which has led some authors to distinguish numerous subspecies, most likely of doubtful status. We can therefore assume that the structure of phylogenetic relationships within the family Strigeidae established so far, based on morphological and molecular criteria (based on single nuclear and mitochondrial markers), does not reflect the actual relationships at the inter- and intra-species level.v

– These studies are also the basis for considering the issue of contemporary parasitological research, i.e. the molecular mechanisms of host specificity formation in digenetic parasites. In fact, we have already preliminarily established that closely related flatworms, occurring in the same biotope, can pursue different life strategies – says Prof. Zaleśny, adding that the project will enable the validation of the GBS method previously not used in research on this group of organisms. The next step will be to apply for a joint National Science Centre project with scientists from two other research centres in order to obtain funding for research into the evolutionary and molecular aspects of the formation of parasite-host systems, the understanding of which is important not only from the perspective of biology, but also, and perhaps above all, that of health and epidemiology.

– Anthropogenic climate change also affects the environment in terms of the parasite-host relationship, which means an increase in parasitic diseases, dangerous also for humans – emphasises Prof. Zaleśny.