Intergeneric Introgression Enhances the Adaptive Potential of Nine-Spined Stickleback (Pungitius pungitius).

Over the past decades, number of evidences has accumulated that demonstrates the importance of genomic introgression between relatively distant eukaryote species, including the introgression of teleost fish species; the three-spined stickleback (Gasterosteus aculeatus) and the nine-spined stickleback (Pungitius pungitius). The whole-genome datasets of both teleost species give reasons for suggesting that the marine population of nine-spined stickleback increases its adaptive potential to the marine environment through introgression with the anadromous three-spined stickleback. These findings demand a reinterpreting of the mechanisms of evolution towards a process in which organisms acquire new traits not only through longterm accumulation and selection of spontaneous mutations, but also via introgression from other species and ecological forms.