Abstract

Species richness is very unevenly distributed across the tree of life. While some lineages diversify rapidly into many species given ecological opportunity, others are much less prone to do so. The factors underlying these differences are poorly understood. Ithomiini butterflies, a tribe of 400 Neotropical butterfly species, are an ideal study system for understanding drivers of rapid diversification. Some ithomiine lineages have diversified exceptionally fast, while others have done so at a much slower pace. By comparing the genetic basis of relevant traits, rates of hybridisation, chromosomal rearrangements and other factors, my group aims to elucidate the factors underlying this variation in diversification rates. We find important roles of hybridisation contributing beneficial genetic variants and chromosomal rearrangements strengthening reproductive isolation. Complex rearrangements involving multiple chromosomes, often including sex chromosomes, seem to play particularly important roles in speciation. Lastly, I will present Project Psyche, a pan-European project to generate reference genomes of all 11’000 species of butterflies and moths in Europe. This megaproject will allow us to study the generality of our findings on speciation and address a wealth of other questions, from agricultural pest management to conservation and symbiotic interactions, to name a few.