Adaptation to the High-Arctic island environment despite long-term reduced genetic variation in Svalbard reindeer
Nicolás Dussex, Ole K. Tørresen, Tom van der Valk, Mathilde Le Moullec, Vebjørn Veiberg, Ave Tooming‐Klunderud, Morten Skage, Benedicte Garmann-Aarhus, Jonathan Wood, Jacob Agerbo Rasmussen, Åshild Ønvik Pedersen, Sarah L F Martin, Knut H. Røed, Kjetill S. Jakobsen, Love Dalén, Brage Bremset Hansen, Michael D. Martin
Abstract
chromosome-level assembly for Svalbard reindeer and analyze 133 reindeer genomes spanning Svalbard and most of the species' Holarctic range, to examine the genomic consequences of long-term isolation and small population size in this insular subspecies. Empirical data, demographic reconstructions, and forward simulations show that long-term isolation and high inbreeding levels may have facilitated the reduction of highly deleterious-and to a lesser extent, moderately deleterious-variation. Our study indicates that long-term reduced genetic diversity did not preclude local adaptation to the High Arctic, suggesting that even severely bottlenecked populations can retain evolutionary potential.