Data from: Drivers of neutral and adaptive differentiation in pike (Esox lucius) populations from contrasting environments

Understanding how eco-evolutionary processes and environmental factors
drive population differentiation and adaptation are key challenges in
evolutionary biology of relevance for biodiversity
protection. Differentiation requires at least partial
reproductive separation, which may result from different modes of
isolation such as geographic isolation (allopatry) or isolation by
distance (IBD), resistance (IBR), and environment
(IBE). Despite that multiple modes might
jointly influence differentiation, studies that compare the
relative contributions are scarce. Using RADseq, we analyse
neutral and adaptive genetic diversity and structure in 11 pike (Esox
lucius) populations along a latitudinal gradient (54.9 - 63.6°N), to
investigate the relative effects of IBD, IBE and IBR, and to assess
whether the effects differ between neutral and adaptive variation, or
across structural levels. Patterns of neutral and adaptive
variation differed, likely reflecting that they have been differently
affected by stochastic and deterministic processes. The
importance of the different modes of isolation differed between neutral
and adaptive diversity, yet were consistent across structural levels.
Neutral variation was influenced by interactions among all three modes of
isolation, with IBR (seascape features) playing a central role, wheares
adaptive variation was mainly influenced by IBE (environmental
conditions). Taken together, this and previous studies suggest
that it is common that multiple modes of isolation interactively shape
patterns of genetic variation, and that their relative contributions
differ among systems. To enable identification of general
patterns and understand how various factors influence the relative
contributions, it is important that several modes are simultaneously
investigated in additional populations, species and environmental
settings.