Within this project I would like to analyse 2bRAD and MethylRAD data from several projects and organisms, mostly eelgrass and shore crabs. The different projects have different questions, but all relate to marine biology and have importance either for conservation or for fundamental evolutionary questions. Apart from genotyping, the analyses I will perform mostly relate to genetic structure and gene flow, and I will perform demographic modelling. I will analyse here some data that has already been generated, and more data from two different projects lead by two different PhD students is planned to come at the end of this year and early next year.