Species delimitation refers to the act of identifying and categorising fundamental entities of nature, i.e., species. But, this process is often challenging and subjective, due to the existence of different species concepts and due to the long and continuous nature of speciation, rendering many taxa falling into so-called the 'grey-zone' of speciation. My doctoral thesis aimed to address this subjectivity and explore the potential of genomic approaches, specifically target enrichment, in making species delimitation more objective. The broader project (funded by Research Council of Finland) included cases of closely related populations/species pairs of Lepidoptera with parapatric, allopatric and sympatric modes of distribution. These case studies (mentioned below) represented examples of long-standing taxonomic challenges that we aimed to resolve with the help of genomic data. I employed phylogenomics, population genetics, species delimitation approaches to assess gene flow, population structure and species boundaries in these different cases. 

Parapatry: Melitaea athalia - Melitaea celadussa, Saturnia pavonia - Saturnia pavoniella
Allopatry - Allopatric populations of Intra-Alpine, Arctic-alpine and Holarctic Lepidoptera
Sympatry: Diachrysia chrysitis - Diachrysia stenochrysis

To read more about the results for each case study, please refer to the list of publications. My doctoral thesis was jointly supervised by Prof. Marko Mutanen (University of Oulu), Dr. Marianne Espeland (LIB, Bonn) and Dr. Maria Heikkilä (Finnish Museum of Natural History, Helsinki).