I am plant ecologist who investigates the response of Paleozoic plants and plant communities to environmental change during periods of mass extinction and deglaciation, and the possible evolutionary consequences. My primary research is focused on several aspects of the end-Permian biotic crisis and its aftermath, and the transition from a glacial-dominated world to an ice-free one during the Late Carboniferous to the Middle Permian. My studies strongly rely on an interdisciplinary approach combining quantitative palynological and paleobotanical data with organic geochemistry, isotope analysis, marine paleontology, biostratigraphy, ecology and plant physiology.