Assistant Professor (post-doc) - Faculty of Biology, University of Warsaw (WB-KG-15/2026)

About this position

The position of Assistant Professor in the programme/project/undertaking The impact of mass extinctions on parasite diversity and evolution.

PI: Dr. hab. Kenneth De Baets, Prof. ucz. Funding institution: National Science Centre Poland.

Description of project:

Parasites are some of the most diverse and ecologically important organisms on Earth. Despite their importance for planetary health, their nature and small size have made them unpopular in nature conservation as well as in fossil diversity studies, where the focus lies on their hosts. In the face of current environmental crisis and unprecedented biodiversity loss, understanding past parasite-host associations are crucial for predicting future shifts in parasite diversity and associated zoonotic disease risk.

Indeed, current models infer future extinctions and host switching based on the modern distribution of symbiont-host associations only. Fossil vertebrate coprolites (fossilized excrements) provide a unique opportunity to see direct changes in parasite prevalence and distribution through past environmental perturbations and can thus fill this lack of knowledge.

The main aim of the project is to model how changes in the host diversity and diet affect the representation and diversity of parasitic helminth (flatworms, nematodes) propagules from the Permian-Triassic mass extinction event and apply this knowledge to current models.

The following research tasks are planned for this project:

• Quantitative sampling of new coprolites from Permian and Triassic outcrops and categorizing them (via morphology, internal structure e.g., obtained by microscopy and computed tomography)
• Subsampling coprolites for thin sections and retrieving food and parasitic inclusions
• Assigning coprolite to the host producer and its diet based on content and structure
• Placing parasite inclusions in phylogeny using machine learning and Total Evidence Approaches
• Modelling the impact of environmental and host factors on parasite diversity and analysis of cophylogenetic extinction risk

The results will improve our understanding of parasite-host co-evolution both in the past and in the present. An unprecedented systematic sampling of coprolites for parasitic helminth propagules across the Permian-Triassic extinction will allow constraining dominant drivers. By combining past extinction data with statistical and co-phylogenetic modeling, we will create new improved models that accurately capture host switching and parasite extinction risk in the future.

Obtained data and extinction models will be useful for fields ranging from conservation biology, over climate change and diversity modelling, to disease and health prediction.

The Postdoc will focus on assembling and performing the total evidence analyses and co-phylogenetic analysis of vertebrate hosts and their helminth parasites. Particularly aligning and assembling the phylogenies as well as further development of Bayesian (co-)phylogenetic analysis to accommodate fossil data to estimate macroevolutionary events as well as improve and simulate extinction risk.