Paper - Introgression from extinct species facilitates adaptation to its vacated niche David Frei published the first paper of his PhD thesis on speciation and its genomics in alpine whitefish. In Lake Constance, an endemic profundal whitefish species went extinct during a period of anthropogenic eutrophication. In the process of extinction, this species hybridized with three surviving whitefish species of Lake Constance, resulting in introgression of genetic variation that is potentially adaptive in deep-water habitats. The results are consistent with the syngameon hypothesis, proposing that hybridization between members of an adaptive radiation can promote further niche expansion and diversification. Furthermore, these findings demonstrate that introgression from extinct into extant species can be a source of evolvability enabling rapid adaptation to environmental change and may contribute to the ecological recovery of ecosystem functions after extinctions.